From patchwork Mon Jun 17 01:46:40 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699861 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D38E115B143; Mon, 17 Jun 2024 01:46:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588806; cv=none; b=NEZ44qZ5rWxJxUgxo6JAAHkPMjtPgARiOeTfs1TxoF0X+Kw0z2UfSYohP39xY7iETw5FLtu7LWsszLxMOpu2maOkKuPO6e0OyOmiBjiJ1EGIGUeGXKnjGZXBUnh2d8zQqjrUFrIoIU9KapMe/Ma5nEuiyOysjIMAI0PBLdmgBho= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588806; c=relaxed/simple; bh=a7Acn7TQ4Iwo2VD7UsmloW71L1XLgtVJhdhvEmYlufU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=Nj9HEwdCY3H+rxyegiYSmhu5fGBb0mTwaNU+SLURDzCZLmRLto475VTi6HcWH8NnKu6lxFNGr2d6ZcAqNqQOGJ+aFALYnIPtyNYV5H3GGddMraKde/UlfIGY09mg8ZURjHTifDY+FahUCvRzVaTjcnqM5PvB3LCIBXjtrCWdFqU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GsHUoEri; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GsHUoEri" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B6C9C2BBFC; Mon, 17 Jun 2024 01:46:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588806; bh=a7Acn7TQ4Iwo2VD7UsmloW71L1XLgtVJhdhvEmYlufU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GsHUoEriOORs5MyU3JbWHr45SjDb6AdlA5ZlGlHf0qZJLqpNkBDJzOA7ZIE/SKAqN LvC7B3laNmTs10QoESD4ologfxr6+wdzRTmyH+89fRL85IW/4e+3HsuE6ks0gk/bNu 0jDoD78qq+1RrqcMDyBCc1yEL4cD5+Eo7rpc97i0Bfxtfpbtr15N6jrPPvFfwXWM2Q GWzD7IQjHqhvY5m11viKuCMsZS8x+yKjqh7U0Gg4NqpZZqBcpJK2QijdAfeQNqZuTl yaeBXDzCTvc8hUk+ZPoc5GWr/0pstarLk6O6e4V9+FXSfDNfwszwmGOWRQ5h2ZKfZv Yn4Irjd9pe/AQ== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 01/18] tracing: Add a comment about ftrace_regs definition Date: Mon, 17 Jun 2024 10:46:40 +0900 Message-Id: <171858879989.288820.8579896574302291995.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) To clarify what will be expected on ftrace_regs, add a comment to the architecture independent definition of the ftrace_regs. Signed-off-by: Masami Hiramatsu (Google) Acked-by: Mark Rutland --- Changes in v8: - Update that the saved registers depends on the context. Changes in v3: - Add instruction pointer Changes in v2: - newly added. --- include/linux/ftrace.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 845c2ab0bc1c..3c8a19ea8f45 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -117,6 +117,32 @@ extern int ftrace_enabled; #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS +/** + * ftrace_regs - ftrace partial/optimal register set + * + * ftrace_regs represents a group of registers which is used at the + * function entry and exit. There are three types of registers. + * + * - Registers for passing the parameters to callee, including the stack + * pointer. (e.g. rcx, rdx, rdi, rsi, r8, r9 and rsp on x86_64) + * - Registers for passing the return values to caller. + * (e.g. rax and rdx on x86_64) + * - Registers for hooking the function call and return including the + * frame pointer (the frame pointer is architecture/config dependent) + * (e.g. rip, rbp and rsp for x86_64) + * + * Also, architecture dependent fields can be used for internal process. + * (e.g. orig_ax on x86_64) + * + * On the function entry, those registers will be restored except for + * the stack pointer, so that user can change the function parameters + * and instruction pointer (e.g. live patching.) + * On the function exit, only registers which is used for return values + * are restored. + * + * NOTE: user *must not* access regs directly, only do it via APIs, because + * the member can be changed according to the architecture. + */ struct ftrace_regs { struct pt_regs regs; }; From patchwork Mon Jun 17 01:46:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699862 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE76B15DBAF; Mon, 17 Jun 2024 01:46:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588818; cv=none; b=hxnIs++vi+OAi7Zqit4k7BeguhEaoUDnLx2oz527DY76CCwPgqe7LIXBUQbubW2fnrHj+LOQ16hQVxAWTEFVsfH271nK+UcxRT2XChFculLv/8nIHggd9tl6qjt3Rt8O4yoIjZfIitehK/zIMocdDkZ8nMgVt0HbGLCKrdP3Uno= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588818; c=relaxed/simple; bh=f79g3hTsdUSefP8Gj3hbCWVNjQerLg05FYmV7kxH30U=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=SBATg6vSGX5L2CNvIXPl/AwYMB2xIcYRKekuJ/1r8xDxi7rr6F8gAbg/ndOjCnjXaDD3+L7/1brqLFw8OEspkPu6XwB8JzkKWp6PNaKEEUhwviD9bz+ew+0XaLQxrQwYm4C+UrUzjKVsDXLknAyminDf5U33aCSGTe9qfmqH2EM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jj586Dg6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jj586Dg6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0C36C2BBFC; Mon, 17 Jun 2024 01:46:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588817; bh=f79g3hTsdUSefP8Gj3hbCWVNjQerLg05FYmV7kxH30U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jj586Dg66HmS3Yr3B5jtmbudglaXvLS7mQU1J7EYIVl4jTAD2nLL48DqvA0z4Nozt HobhUo9mUV4sZkDQiQN4AwxJ1aF80wW65AqHdZn1qw42sOUitWz9PnDeDiPnroBkfx H/AGkS2pnSmWJVxNwWzzW79AqHLbaGJZZoJBMPRpQ0UpU/8wVU4F6xb58VZvu0x1Vi VCpByiOFsCViYjRT4sesqAUVJ3a970klqE86V/ZX81PtDuRkxYxBZOUhwSHDXWsoEc m87aXSTAFRmrOnXHlpuDOeZA00LA+mV1old8/VTLdLzdeggFl/EglW9bq+GjR9dkn9 NRzYcCH7ts9pQ== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 02/18] tracing: Rename ftrace_regs_return_value to ftrace_regs_get_return_value Date: Mon, 17 Jun 2024 10:46:51 +0900 Message-Id: <171858881136.288820.9563156284766465616.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Rename ftrace_regs_return_value to ftrace_regs_get_return_value as same as other ftrace_regs_get/set_* APIs. Signed-off-by: Masami Hiramatsu (Google) Acked-by: Mark Rutland --- Changes in v6: - Moved to top of the series. Changes in v3: - Newly added. --- arch/loongarch/include/asm/ftrace.h | 2 +- arch/powerpc/include/asm/ftrace.h | 2 +- arch/s390/include/asm/ftrace.h | 2 +- arch/x86/include/asm/ftrace.h | 2 +- include/linux/ftrace.h | 2 +- 5 files changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index c0a682808e07..6f8517d59954 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -69,7 +69,7 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) regs_get_kernel_argument(&(fregs)->regs, n) #define ftrace_regs_get_stack_pointer(fregs) \ kernel_stack_pointer(&(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ +#define ftrace_regs_get_return_value(fregs) \ regs_return_value(&(fregs)->regs) #define ftrace_regs_set_return_value(fregs, ret) \ regs_set_return_value(&(fregs)->regs, ret) diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index 559560286e6d..23d26f3afae4 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -59,7 +59,7 @@ ftrace_regs_get_instruction_pointer(struct ftrace_regs *fregs) regs_get_kernel_argument(&(fregs)->regs, n) #define ftrace_regs_get_stack_pointer(fregs) \ kernel_stack_pointer(&(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ +#define ftrace_regs_get_return_value(fregs) \ regs_return_value(&(fregs)->regs) #define ftrace_regs_set_return_value(fregs, ret) \ regs_set_return_value(&(fregs)->regs, ret) diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index fbadca645af7..de76c21eb4a3 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -83,7 +83,7 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, regs_get_kernel_argument(&(fregs)->regs, n) #define ftrace_regs_get_stack_pointer(fregs) \ kernel_stack_pointer(&(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ +#define ftrace_regs_get_return_value(fregs) \ regs_return_value(&(fregs)->regs) #define ftrace_regs_set_return_value(fregs, ret) \ regs_set_return_value(&(fregs)->regs, ret) diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 0152a81d9b4a..78f6a200e15b 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -56,7 +56,7 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) regs_get_kernel_argument(&(fregs)->regs, n) #define ftrace_regs_get_stack_pointer(fregs) \ kernel_stack_pointer(&(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ +#define ftrace_regs_get_return_value(fregs) \ regs_return_value(&(fregs)->regs) #define ftrace_regs_set_return_value(fregs, ret) \ regs_set_return_value(&(fregs)->regs, ret) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 3c8a19ea8f45..bf04b29f9da1 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -183,7 +183,7 @@ static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs) regs_get_kernel_argument(ftrace_get_regs(fregs), n) #define ftrace_regs_get_stack_pointer(fregs) \ kernel_stack_pointer(ftrace_get_regs(fregs)) -#define ftrace_regs_return_value(fregs) \ +#define ftrace_regs_get_return_value(fregs) \ regs_return_value(ftrace_get_regs(fregs)) #define ftrace_regs_set_return_value(fregs, ret) \ regs_set_return_value(ftrace_get_regs(fregs), ret) From patchwork Mon Jun 17 01:47:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699863 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A8C7615DBBB; Mon, 17 Jun 2024 01:47:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588829; cv=none; b=OKNcWu7KHktspJZFKqIbtc8i+p2oRd0J2m5a8OfChc1EnvFByeLSs5IwFgh4TK/lYu6xgUh8X5rEMph6dqlYgUusY0MszzKjK2V8r9cJrQIEeKYRjkdELeVONr4WXk+q8W82YqcwnCSKG/Fqj7CgRLgVYLvPG372eaVYz3h5soE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588829; c=relaxed/simple; bh=Vdp7IpJZyyXWfPyFQvIr4bzF00gAu9M3nlHSqCOcEbQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=GAI5PPFeh7rWyL1apqp+VI9ODPILvYHDgLBnx9lil7H3Cuac1doVF6jWxkHfNJce/987y4Optj08cARm5T7G8yVV9i2zB1rSNZs3zfZ/BTKgf758CGmRL7d8OBhPge0XA73f3nGjBixaNffRTNfIRk45Lgm+Y3JPMmq5mRf/kmg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S2PZwE7/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="S2PZwE7/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E70AC4AF1C; Mon, 17 Jun 2024 01:47:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588829; bh=Vdp7IpJZyyXWfPyFQvIr4bzF00gAu9M3nlHSqCOcEbQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S2PZwE7/ZDlggCduX4MEyXi82CuFf3BefZ7k+ur3onhxXr+Z1MR8nU5xLMxb4ZYJX 1EEdhgJmK6UVBFC8F69Z46iNbSIh3vQqhPzJ6PfaaVSenpAsDA6+x/GNIuCRC+k+JL aP70kgNbHt1i8GOXPzwJ9a1gw6WYJvr1SCGfiwB9fGJ1YWSK1mJ/IxI3oCoC4kQ6K+ jXg6FCuICOa6IQsQGo6n03SYrCSCkzYCA3sRIj8QK7dQCYgqQ1hYWN0L/oIUO510MI QzA0M5SU6piTopZVsckqq/eMXlWLDytDHQK7O0nEJaBuBXx5HxxNyZglvTitf3Zmlh UyltZJVdHulXg== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 03/18] function_graph: Pass ftrace_regs to entryfunc Date: Mon, 17 Jun 2024 10:47:02 +0900 Message-Id: <171858882283.288820.9575847272646773088.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Pass ftrace_regs to the fgraph_ops::entryfunc(). If ftrace_regs is not available, it passes a NULL instead. User callback function can access some registers (including return address) via this ftrace_regs. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v11: - Update for the latest for-next branch. Changes in v8: - Just pass ftrace_regs to the handler instead of adding a new entryregfunc. - Update riscv ftrace_graph_func(). Changes in v3: - Update for new multiple fgraph. --- arch/arm64/kernel/ftrace.c | 20 +++++++++++- arch/loongarch/kernel/ftrace_dyn.c | 10 +++++- arch/powerpc/kernel/trace/ftrace.c | 2 + arch/powerpc/kernel/trace/ftrace_64_pg.c | 10 ++++-- arch/riscv/kernel/ftrace.c | 17 ++++++++++ arch/x86/kernel/ftrace.c | 50 +++++++++++++++++++++--------- include/linux/ftrace.h | 18 ++++++++--- kernel/trace/fgraph.c | 23 ++++++++------ kernel/trace/ftrace.c | 3 +- kernel/trace/trace.h | 3 +- kernel/trace/trace_functions_graph.c | 3 +- kernel/trace/trace_irqsoff.c | 3 +- kernel/trace/trace_sched_wakeup.c | 3 +- kernel/trace/trace_selftest.c | 8 +++-- 14 files changed, 128 insertions(+), 45 deletions(-) diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index a650f5e11fc5..bc647b725e6a 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -481,7 +481,25 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { - prepare_ftrace_return(ip, &fregs->lr, fregs->fp); + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long frame_pointer = fregs->fp; + unsigned long *parent = &fregs->lr; + unsigned long old; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + /* + * Note: + * No protection against faulting at *parent, which may be seen + * on other archs. It's unlikely on AArch64. + */ + old = *parent; + + if (!function_graph_enter_regs(old, ip, frame_pointer, + (void *)frame_pointer, fregs)) { + *parent = return_hooker; + } } #else /* diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c index bff058317062..966e0f7f7aca 100644 --- a/arch/loongarch/kernel/ftrace_dyn.c +++ b/arch/loongarch/kernel/ftrace_dyn.c @@ -243,8 +243,16 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, { struct pt_regs *regs = &fregs->regs; unsigned long *parent = (unsigned long *)®s->regs[1]; + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long old; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + old = *parent; - prepare_ftrace_return(ip, (unsigned long *)parent); + if (!function_graph_enter_regs(old, ip, 0, parent, fregs)) + *parent = return_hooker; } #else static int ftrace_modify_graph_caller(bool enable) diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index d8d6b4fd9a14..a1a0e0b57662 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -434,7 +434,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, if (bit < 0) goto out; - if (!function_graph_enter(parent_ip, ip, 0, (unsigned long *)sp)) + if (!function_graph_enter_regs(parent_ip, ip, 0, (unsigned long *)sp, fregs)) parent_ip = ppc_function_entry(return_to_handler); ftrace_test_recursion_unlock(bit); diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.c b/arch/powerpc/kernel/trace/ftrace_64_pg.c index 12fab1803bcf..4ae9eeb1c8f1 100644 --- a/arch/powerpc/kernel/trace/ftrace_64_pg.c +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c @@ -800,7 +800,8 @@ int ftrace_disable_ftrace_graph_caller(void) * in current thread info. Return the address we want to divert to. */ static unsigned long -__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp) +__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp, + struct ftrace_regs *fregs) { unsigned long return_hooker; int bit; @@ -817,7 +818,7 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp return_hooker = ppc_function_entry(return_to_handler); - if (!function_graph_enter(parent, ip, 0, (unsigned long *)sp)) + if (!function_graph_enter_regs(parent, ip, 0, (unsigned long *)sp, fregs)) parent = return_hooker; ftrace_test_recursion_unlock(bit); @@ -829,13 +830,14 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { - fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]); + fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, + fregs->regs.gpr[1], fregs); } #else unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp) { - return __prepare_ftrace_return(parent, ip, sp); + return __prepare_ftrace_return(parent, ip, sp, NULL); } #endif #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c index 87cbd86576b2..42ec55da088c 100644 --- a/arch/riscv/kernel/ftrace.c +++ b/arch/riscv/kernel/ftrace.c @@ -217,7 +217,22 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { - prepare_ftrace_return(&fregs->ra, ip, fregs->s0); + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long frame_pointer = fregs->s0; + unsigned long *parent = &fregs->ra; + unsigned long old; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + /* + * We don't suffer access faults, so no extra fault-recovery assembly + * is needed here. + */ + old = *parent; + + if (!function_graph_enter_regs(old, ip, frame_pointer, parent, fregs)) + *parent = return_hooker; } #else /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */ extern void ftrace_graph_call(void); diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 8da0e66ca22d..decf4c11dcf3 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -605,16 +605,8 @@ int ftrace_disable_ftrace_graph_caller(void) } #endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ -/* - * Hook the return address and push it in the stack of return addrs - * in current thread info. - */ -void prepare_ftrace_return(unsigned long ip, unsigned long *parent, - unsigned long frame_pointer) +static inline bool skip_ftrace_return(void) { - unsigned long return_hooker = (unsigned long)&return_to_handler; - int bit; - /* * When resuming from suspend-to-ram, this function can be indirectly * called from early CPU startup code while the CPU is in real mode, @@ -624,13 +616,28 @@ void prepare_ftrace_return(unsigned long ip, unsigned long *parent, * This check isn't as accurate as virt_addr_valid(), but it should be * good enough for this purpose, and it's fast. */ - if (unlikely((long)__builtin_frame_address(0) >= 0)) - return; + if ((long)__builtin_frame_address(0) >= 0) + return true; - if (unlikely(ftrace_graph_is_dead())) - return; + if (ftrace_graph_is_dead()) + return true; + + if (atomic_read(¤t->tracing_graph_pause)) + return true; + return false; +} + +/* + * Hook the return address and push it in the stack of return addrs + * in current thread info. + */ +void prepare_ftrace_return(unsigned long ip, unsigned long *parent, + unsigned long frame_pointer) +{ + unsigned long return_hooker = (unsigned long)&return_to_handler; + int bit; - if (unlikely(atomic_read(¤t->tracing_graph_pause))) + if (unlikely(skip_ftrace_return())) return; bit = ftrace_test_recursion_trylock(ip, *parent); @@ -649,8 +656,21 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, { struct pt_regs *regs = &fregs->regs; unsigned long *stack = (unsigned long *)kernel_stack_pointer(regs); + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long *parent = (unsigned long *)stack; + int bit; - prepare_ftrace_return(ip, (unsigned long *)stack, 0); + if (unlikely(skip_ftrace_return())) + return; + + bit = ftrace_test_recursion_trylock(ip, *parent); + if (bit < 0) + return; + + if (!function_graph_enter_regs(*parent, ip, 0, parent, fregs)) + *parent = return_hooker; + + ftrace_test_recursion_unlock(bit); } #endif diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index bf04b29f9da1..dc2e8073aa79 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -1063,9 +1063,12 @@ struct fgraph_ops; typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *, struct fgraph_ops *); /* return */ typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *, - struct fgraph_ops *); /* entry */ + struct fgraph_ops *, + struct ftrace_regs *); /* entry */ -extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph_ops *gops); +extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, + struct fgraph_ops *gops, + struct ftrace_regs *fregs); bool ftrace_pids_enabled(struct ftrace_ops *ops); #ifdef CONFIG_FUNCTION_GRAPH_TRACER @@ -1108,8 +1111,15 @@ struct ftrace_ret_stack { extern void return_to_handler(void); extern int -function_graph_enter(unsigned long ret, unsigned long func, - unsigned long frame_pointer, unsigned long *retp); +function_graph_enter_regs(unsigned long ret, unsigned long func, + unsigned long frame_pointer, unsigned long *retp, + struct ftrace_regs *fregs); + +static inline int function_graph_enter(unsigned long ret, unsigned long func, + unsigned long fp, unsigned long *retp) +{ + return function_graph_enter_regs(ret, func, fp, retp, NULL); +} struct ftrace_ret_stack * ftrace_graph_get_ret_stack(struct task_struct *task, int skip); diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 8317d1a7f43a..269f10d02046 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -290,7 +290,8 @@ static inline unsigned long make_data_type_val(int idx, int size, int offset) } /* ftrace_graph_entry set to this to tell some archs to run function graph */ -static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops) +static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops, + struct ftrace_regs *fregs) { return 0; } @@ -484,7 +485,7 @@ int __weak ftrace_disable_ftrace_graph_caller(void) #endif int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, struct ftrace_regs *fregs) { return 0; } @@ -612,8 +613,9 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, #endif /* If the caller does not use ftrace, call this function. */ -int function_graph_enter(unsigned long ret, unsigned long func, - unsigned long frame_pointer, unsigned long *retp) +int function_graph_enter_regs(unsigned long ret, unsigned long func, + unsigned long frame_pointer, unsigned long *retp, + struct ftrace_regs *fregs) { struct ftrace_graph_ent trace; unsigned long bitmap = 0; @@ -631,7 +633,7 @@ int function_graph_enter(unsigned long ret, unsigned long func, if (static_branch_likely(&fgraph_do_direct)) { int save_curr_ret_stack = current->curr_ret_stack; - if (static_call(fgraph_func)(&trace, fgraph_direct_gops)) + if (static_call(fgraph_func)(&trace, fgraph_direct_gops, fregs)) bitmap |= BIT(fgraph_direct_gops->idx); else /* Clear out any saved storage */ @@ -649,7 +651,7 @@ int function_graph_enter(unsigned long ret, unsigned long func, save_curr_ret_stack = current->curr_ret_stack; if (ftrace_ops_test(&gops->ops, func, NULL) && - gops->entryfunc(&trace, gops)) + gops->entryfunc(&trace, gops, fregs)) bitmap |= BIT(i); else /* Clear out any saved storage */ @@ -925,7 +927,7 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, static struct ftrace_ops graph_ops = { .func = ftrace_graph_func, - .flags = FTRACE_OPS_GRAPH_STUB, + .flags = FTRACE_OPS_GRAPH_STUB | FTRACE_OPS_FL_SAVE_ARGS, #ifdef FTRACE_GRAPH_TRAMP_ADDR .trampoline = FTRACE_GRAPH_TRAMP_ADDR, /* trampoline_size is only needed for dynamically allocated tramps */ @@ -935,7 +937,8 @@ static struct ftrace_ops graph_ops = { void fgraph_init_ops(struct ftrace_ops *dst_ops, struct ftrace_ops *src_ops) { - dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB; + dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB | + FTRACE_OPS_FL_SAVE_ARGS; #ifdef CONFIG_DYNAMIC_FTRACE if (src_ops) { @@ -1119,7 +1122,7 @@ void ftrace_graph_exit_task(struct task_struct *t) #ifdef CONFIG_DYNAMIC_FTRACE static int fgraph_pid_func(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, struct ftrace_regs *fregs) { struct trace_array *tr = gops->ops.private; int pid; @@ -1133,7 +1136,7 @@ static int fgraph_pid_func(struct ftrace_graph_ent *trace, return 0; } - return gops->saved_func(trace, gops); + return gops->saved_func(trace, gops, fregs); } void fgraph_update_pid_func(void) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f44229294e9d..64d15428cffc 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -821,7 +821,8 @@ void ftrace_graph_graph_time_control(bool enable) } static int profile_graph_entry(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct ftrace_ret_stack *ret_stack; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 8783bebd0562..2b718e448026 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -683,7 +683,8 @@ void trace_default_header(struct seq_file *m); void print_trace_header(struct seq_file *m, struct trace_iterator *iter); void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops); -int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops); +int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops, + struct ftrace_regs *fregs); void tracing_start_cmdline_record(void); void tracing_stop_cmdline_record(void); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 13d0387ac6a6..b9785fc919c9 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -128,7 +128,8 @@ static inline int ftrace_graph_ignore_irqs(void) } int trace_graph_entry(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { unsigned long *task_var = fgraph_get_task_var(gops); struct trace_array *tr = gops->private; diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index fce064e20570..ad739d76fc86 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -176,7 +176,8 @@ static int irqsoff_display_graph(struct trace_array *tr, int set) } static int irqsoff_graph_entry(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct trace_array *tr = irqsoff_trace; struct trace_array_cpu *data; diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 130ca7e7787e..23360a2700de 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -113,7 +113,8 @@ static int wakeup_display_graph(struct trace_array *tr, int set) } static int wakeup_graph_entry(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct trace_array *tr = wakeup_trace; struct trace_array_cpu *data; diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index adf0f436d84b..92c16e99d4f2 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -773,7 +773,8 @@ struct fgraph_fixture { }; static __init int store_entry(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops); const char *type = fixture->store_type_name; @@ -1011,7 +1012,8 @@ static unsigned int graph_hang_thresh; /* Wrap the real function entry probe to avoid possible hanging */ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { /* This is harmlessly racy, we want to approximately detect a hang */ if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) { @@ -1025,7 +1027,7 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace, return 0; } - return trace_graph_entry(trace, gops); + return trace_graph_entry(trace, gops, fregs); } static struct fgraph_ops fgraph_ops __initdata = { From patchwork Mon Jun 17 01:47:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699864 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 80E2E15F41B; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZGBmRc8b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9817C2BBFC; Mon, 17 Jun 2024 01:47:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588841; bh=DeQy8Ln2KWtQNWrjqzggUyFwCO3yPubgWjLdO8a515A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZGBmRc8bPUK033w40MVjME1CI949ixUoSrsWEBq2mZHBvpakyrUVqv/Bw9Gsm+rkB AJoUN4gU+UOTGWKHMBw1U3X0nAcJEi9lGQxny2aXzauGxaI+HsDxz7qImZfAURS8rq 2vVpgI1tohHMQYIq+ZQS1lw2T/5f0UchC/uRTJ5eXbAqRyVWsZs1AxEZKrQQWiOKP0 5H9gXoNaHYrfK1VIRRNoOB8s4R6xdkI8CleN0WWI/M/HwhWG9RYM8vyYNKAY9f+dI3 rVjnZPncND1P5KefU92UX587v2CdMFO6R2yF6lv95Al/HFezyrgwynnmTpjYbQfiJP i3rWZ5mUXq1vA== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 04/18] function_graph: Replace fgraph_ret_regs with ftrace_regs Date: Mon, 17 Jun 2024 10:47:14 +0900 Message-Id: <171858883461.288820.1408436938551720400.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Use ftrace_regs instead of fgraph_ret_regs for tracing return value on function_graph tracer because of simplifying the callback interface. The CONFIG_HAVE_FUNCTION_GRAPH_RETVAL is also replaced by CONFIG_HAVE_FUNCTION_GRAPH_FREGS. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v8: - Newly added. --- arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/ftrace.h | 23 ++++++----------------- arch/arm64/kernel/asm-offsets.c | 12 ------------ arch/arm64/kernel/entry-ftrace.S | 32 ++++++++++++++++++-------------- arch/loongarch/Kconfig | 2 +- arch/loongarch/include/asm/ftrace.h | 24 ++---------------------- arch/loongarch/kernel/asm-offsets.c | 12 ------------ arch/loongarch/kernel/mcount.S | 17 ++++++++++------- arch/loongarch/kernel/mcount_dyn.S | 14 +++++++------- arch/riscv/Kconfig | 2 +- arch/riscv/include/asm/ftrace.h | 26 +++++--------------------- arch/riscv/kernel/mcount.S | 24 +++++++++++++----------- arch/s390/Kconfig | 2 +- arch/s390/include/asm/ftrace.h | 26 +++++++++----------------- arch/s390/kernel/asm-offsets.c | 6 ------ arch/s390/kernel/mcount.S | 9 +++++---- arch/x86/Kconfig | 2 +- arch/x86/include/asm/ftrace.h | 22 ++-------------------- arch/x86/kernel/ftrace_32.S | 15 +++++++++------ arch/x86/kernel/ftrace_64.S | 17 +++++++++-------- include/linux/ftrace.h | 14 +++++++++++--- kernel/trace/Kconfig | 4 ++-- kernel/trace/fgraph.c | 21 +++++++++------------ 23 files changed, 122 insertions(+), 206 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 5d91259ee7b5..8691683d782e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -210,7 +210,7 @@ config ARM64 select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_TRACER select HAVE_FUNCTION_ERROR_INJECTION - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER + select HAVE_FUNCTION_GRAPH_FREGS select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GCC_PLUGINS select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \ diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index dc9cf0bd2a4c..dffaab3dd1f1 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -126,6 +126,12 @@ ftrace_override_function_with_return(struct ftrace_regs *fregs) fregs->pc = fregs->lr; } +static __always_inline unsigned long +ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) +{ + return fregs->fp; +} + int ftrace_regs_query_register_offset(const char *name); int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); @@ -183,23 +189,6 @@ static inline bool arch_syscall_match_sym_name(const char *sym, #ifndef __ASSEMBLY__ #ifdef CONFIG_FUNCTION_GRAPH_TRACER -struct fgraph_ret_regs { - /* x0 - x7 */ - unsigned long regs[8]; - - unsigned long fp; - unsigned long __unused; -}; - -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->regs[0]; -} - -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->fp; -} void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, unsigned long frame_pointer); diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 81496083c041..81bb6704ff5a 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -200,18 +200,6 @@ int main(void) DEFINE(FTRACE_OPS_FUNC, offsetof(struct ftrace_ops, func)); #endif BLANK(); -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - DEFINE(FGRET_REGS_X0, offsetof(struct fgraph_ret_regs, regs[0])); - DEFINE(FGRET_REGS_X1, offsetof(struct fgraph_ret_regs, regs[1])); - DEFINE(FGRET_REGS_X2, offsetof(struct fgraph_ret_regs, regs[2])); - DEFINE(FGRET_REGS_X3, offsetof(struct fgraph_ret_regs, regs[3])); - DEFINE(FGRET_REGS_X4, offsetof(struct fgraph_ret_regs, regs[4])); - DEFINE(FGRET_REGS_X5, offsetof(struct fgraph_ret_regs, regs[5])); - DEFINE(FGRET_REGS_X6, offsetof(struct fgraph_ret_regs, regs[6])); - DEFINE(FGRET_REGS_X7, offsetof(struct fgraph_ret_regs, regs[7])); - DEFINE(FGRET_REGS_FP, offsetof(struct fgraph_ret_regs, fp)); - DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs)); -#endif #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS DEFINE(FTRACE_OPS_DIRECT_CALL, offsetof(struct ftrace_ops, direct_call)); #endif diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S index f0c16640ef21..169ccf600066 100644 --- a/arch/arm64/kernel/entry-ftrace.S +++ b/arch/arm64/kernel/entry-ftrace.S @@ -329,24 +329,28 @@ SYM_FUNC_END(ftrace_stub_graph) * @fp is checked against the value passed by ftrace_graph_caller(). */ SYM_CODE_START(return_to_handler) - /* save return value regs */ - sub sp, sp, #FGRET_REGS_SIZE - stp x0, x1, [sp, #FGRET_REGS_X0] - stp x2, x3, [sp, #FGRET_REGS_X2] - stp x4, x5, [sp, #FGRET_REGS_X4] - stp x6, x7, [sp, #FGRET_REGS_X6] - str x29, [sp, #FGRET_REGS_FP] // parent's fp + /* Make room for ftrace_regs */ + sub sp, sp, #FREGS_SIZE + + /* Save return value regs */ + stp x0, x1, [sp, #FREGS_X0] + stp x2, x3, [sp, #FREGS_X2] + stp x4, x5, [sp, #FREGS_X4] + stp x6, x7, [sp, #FREGS_X6] + + /* Save the callsite's FP */ + str x29, [sp, #FREGS_FP] mov x0, sp - bl ftrace_return_to_handler // addr = ftrace_return_to_hander(regs); + bl ftrace_return_to_handler // addr = ftrace_return_to_hander(fregs); mov x30, x0 // restore the original return address - /* restore return value regs */ - ldp x0, x1, [sp, #FGRET_REGS_X0] - ldp x2, x3, [sp, #FGRET_REGS_X2] - ldp x4, x5, [sp, #FGRET_REGS_X4] - ldp x6, x7, [sp, #FGRET_REGS_X6] - add sp, sp, #FGRET_REGS_SIZE + /* Restore return value regs */ + ldp x0, x1, [sp, #FREGS_X0] + ldp x2, x3, [sp, #FREGS_X2] + ldp x4, x5, [sp, #FREGS_X4] + ldp x6, x7, [sp, #FREGS_X6] + add sp, sp, #FREGS_SIZE ret SYM_CODE_END(return_to_handler) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index e38139c576ee..23014d5f0047 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -128,7 +128,7 @@ config LOONGARCH select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_ARG_ACCESS_API select HAVE_FUNCTION_ERROR_INJECTION - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER + select HAVE_FUNCTION_GRAPH_FREGS select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER select HAVE_GCC_PLUGINS diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index 6f8517d59954..1a73f35ea9af 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -77,6 +77,8 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) override_function_with_return(&(fregs)->regs) #define ftrace_regs_query_register_offset(name) \ regs_query_register_offset(name) +#define ftrace_regs_get_frame_pointer(fregs) \ + ((fregs)->regs.regs[22]) #define ftrace_graph_func ftrace_graph_func void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, @@ -99,26 +101,4 @@ __arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr) #endif /* CONFIG_FUNCTION_TRACER */ -#ifndef __ASSEMBLY__ -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -struct fgraph_ret_regs { - /* a0 - a1 */ - unsigned long regs[2]; - - unsigned long fp; - unsigned long __unused; -}; - -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->regs[0]; -} - -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->fp; -} -#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ -#endif - #endif /* _ASM_LOONGARCH_FTRACE_H */ diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c index bee9f7a3108f..714f5b5f1956 100644 --- a/arch/loongarch/kernel/asm-offsets.c +++ b/arch/loongarch/kernel/asm-offsets.c @@ -279,18 +279,6 @@ static void __used output_pbe_defines(void) } #endif -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -static void __used output_fgraph_ret_regs_defines(void) -{ - COMMENT("LoongArch fgraph_ret_regs offsets."); - OFFSET(FGRET_REGS_A0, fgraph_ret_regs, regs[0]); - OFFSET(FGRET_REGS_A1, fgraph_ret_regs, regs[1]); - OFFSET(FGRET_REGS_FP, fgraph_ret_regs, fp); - DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs)); - BLANK(); -} -#endif - static void __used output_kvm_defines(void) { COMMENT("KVM/LoongArch Specific offsets."); diff --git a/arch/loongarch/kernel/mcount.S b/arch/loongarch/kernel/mcount.S index 3015896016a0..b6850503e061 100644 --- a/arch/loongarch/kernel/mcount.S +++ b/arch/loongarch/kernel/mcount.S @@ -79,10 +79,11 @@ SYM_FUNC_START(ftrace_graph_caller) SYM_FUNC_END(ftrace_graph_caller) SYM_FUNC_START(return_to_handler) - PTR_ADDI sp, sp, -FGRET_REGS_SIZE - PTR_S a0, sp, FGRET_REGS_A0 - PTR_S a1, sp, FGRET_REGS_A1 - PTR_S zero, sp, FGRET_REGS_FP + /* Save return value regs */ + PTR_ADDI sp, sp, -PT_SIZE + PTR_S a0, sp, PT_R4 + PTR_S a1, sp, PT_R5 + PTR_S zero, sp, PT_R22 move a0, sp bl ftrace_return_to_handler @@ -90,9 +91,11 @@ SYM_FUNC_START(return_to_handler) /* Restore the real parent address: a0 -> ra */ move ra, a0 - PTR_L a0, sp, FGRET_REGS_A0 - PTR_L a1, sp, FGRET_REGS_A1 - PTR_ADDI sp, sp, FGRET_REGS_SIZE + /* Restore return value regs */ + PTR_L a0, sp, PT_R4 + PTR_L a1, sp, PT_R5 + PTR_ADDI sp, sp, PT_SIZE + jr ra SYM_FUNC_END(return_to_handler) #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/loongarch/kernel/mcount_dyn.S b/arch/loongarch/kernel/mcount_dyn.S index 0c65cf09110c..d6b474ad1d5e 100644 --- a/arch/loongarch/kernel/mcount_dyn.S +++ b/arch/loongarch/kernel/mcount_dyn.S @@ -140,19 +140,19 @@ SYM_CODE_END(ftrace_graph_caller) SYM_CODE_START(return_to_handler) UNWIND_HINT_UNDEFINED /* Save return value regs */ - PTR_ADDI sp, sp, -FGRET_REGS_SIZE - PTR_S a0, sp, FGRET_REGS_A0 - PTR_S a1, sp, FGRET_REGS_A1 - PTR_S zero, sp, FGRET_REGS_FP + PTR_ADDI sp, sp, -PT_SIZE + PTR_S a0, sp, PT_R4 + PTR_S a1, sp, PT_R5 + PTR_S zero, sp, PT_R22 move a0, sp bl ftrace_return_to_handler move ra, a0 /* Restore return value regs */ - PTR_L a0, sp, FGRET_REGS_A0 - PTR_L a1, sp, FGRET_REGS_A1 - PTR_ADDI sp, sp, FGRET_REGS_SIZE + PTR_L a0, sp, PT_R4 + PTR_L a1, sp, PT_R5 + PTR_ADDI sp, sp, PT_SIZE jr ra SYM_CODE_END(return_to_handler) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 0525ee2d63c7..1904393bc399 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -132,7 +132,7 @@ config RISCV select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL select HAVE_FUNCTION_GRAPH_TRACER - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER + select HAVE_FUNCTION_GRAPH_FREGS select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION select HAVE_EBPF_JIT if MMU select HAVE_GUP_FAST if MMU diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index 2cddd79ff21b..e9f364ce9fe8 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -164,6 +164,11 @@ static __always_inline unsigned long ftrace_regs_get_stack_pointer(const struct return fregs->sp; } +static __always_inline unsigned long ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) +{ + return fregs->s0; +} + static __always_inline unsigned long ftrace_regs_get_argument(struct ftrace_regs *fregs, unsigned int n) { @@ -204,25 +209,4 @@ static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsi #endif /* CONFIG_DYNAMIC_FTRACE */ -#ifndef __ASSEMBLY__ -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -struct fgraph_ret_regs { - unsigned long a1; - unsigned long a0; - unsigned long s0; - unsigned long ra; -}; - -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->a0; -} - -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->s0; -} -#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ -#endif - #endif /* _ASM_RISCV_FTRACE_H */ diff --git a/arch/riscv/kernel/mcount.S b/arch/riscv/kernel/mcount.S index 3a42f6287909..068168046e0e 100644 --- a/arch/riscv/kernel/mcount.S +++ b/arch/riscv/kernel/mcount.S @@ -12,6 +12,8 @@ #include #include +#define ABI_SIZE_ON_STACK 80 + .text .macro SAVE_ABI_STATE @@ -26,12 +28,12 @@ * register if a0 was not saved. */ .macro SAVE_RET_ABI_STATE - addi sp, sp, -4*SZREG - REG_S s0, 2*SZREG(sp) - REG_S ra, 3*SZREG(sp) - REG_S a0, 1*SZREG(sp) - REG_S a1, 0*SZREG(sp) - addi s0, sp, 4*SZREG + addi sp, sp, -ABI_SIZE_ON_STACK + REG_S ra, 1*SZREG(sp) + REG_S s0, 8*SZREG(sp) + REG_S a0, 10*SZREG(sp) + REG_S a1, 11*SZREG(sp) + addi s0, sp, ABI_SIZE_ON_STACK .endm .macro RESTORE_ABI_STATE @@ -41,11 +43,11 @@ .endm .macro RESTORE_RET_ABI_STATE - REG_L ra, 3*SZREG(sp) - REG_L s0, 2*SZREG(sp) - REG_L a0, 1*SZREG(sp) - REG_L a1, 0*SZREG(sp) - addi sp, sp, 4*SZREG + REG_L ra, 1*SZREG(sp) + REG_L s0, 8*SZREG(sp) + REG_L a0, 10*SZREG(sp) + REG_L a1, 11*SZREG(sp) + addi sp, sp, ABI_SIZE_ON_STACK .endm SYM_TYPED_FUNC_START(ftrace_stub) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index c59d2b54df49..33688d43fd14 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -182,7 +182,7 @@ config S390 select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_ARG_ACCESS_API select HAVE_FUNCTION_ERROR_INJECTION - select HAVE_FUNCTION_GRAPH_RETVAL + select HAVE_FUNCTION_GRAPH_FREGS select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER select HAVE_GCC_PLUGINS diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index de76c21eb4a3..9cdd48a46bf7 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -49,23 +49,6 @@ static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs * return NULL; } -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -struct fgraph_ret_regs { - unsigned long gpr2; - unsigned long fp; -}; - -static __always_inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->gpr2; -} - -static __always_inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->fp; -} -#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ - static __always_inline unsigned long ftrace_regs_get_instruction_pointer(const struct ftrace_regs *fregs) { @@ -92,6 +75,15 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, #define ftrace_regs_query_register_offset(name) \ regs_query_register_offset(name) +static __always_inline unsigned long +ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs) +{ + unsigned long *sp; + + sp = (void *)ftrace_regs_get_stack_pointer(fregs); + return sp[0]; /* return backchain */ +} + #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS /* * When an ftrace registered caller is tracing a function that is diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index f55979f64d49..8c78a1d4936f 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -177,12 +177,6 @@ int main(void) DEFINE(OLDMEM_SIZE, PARMAREA + offsetof(struct parmarea, oldmem_size)); DEFINE(COMMAND_LINE, PARMAREA + offsetof(struct parmarea, command_line)); DEFINE(MAX_COMMAND_LINE_SIZE, PARMAREA + offsetof(struct parmarea, max_command_line_size)); -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - /* function graph return value tracing */ - OFFSET(__FGRAPH_RET_GPR2, fgraph_ret_regs, gpr2); - OFFSET(__FGRAPH_RET_FP, fgraph_ret_regs, fp); - DEFINE(__FGRAPH_RET_SIZE, sizeof(struct fgraph_ret_regs)); -#endif OFFSET(__FTRACE_REGS_PT_REGS, ftrace_regs, regs); DEFINE(__FTRACE_REGS_SIZE, sizeof(struct ftrace_regs)); return 0; diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S index ae4d4fd9afcd..cda798b976de 100644 --- a/arch/s390/kernel/mcount.S +++ b/arch/s390/kernel/mcount.S @@ -133,14 +133,15 @@ SYM_CODE_END(ftrace_common) SYM_FUNC_START(return_to_handler) stmg %r2,%r5,32(%r15) lgr %r1,%r15 - aghi %r15,-(STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE) +# Allocate ftrace_regs + backchain on the stack + aghi %r15,-STACK_FRAME_SIZE_FREGS stg %r1,__SF_BACKCHAIN(%r15) la %r3,STACK_FRAME_OVERHEAD(%r15) - stg %r1,__FGRAPH_RET_FP(%r3) - stg %r2,__FGRAPH_RET_GPR2(%r3) + stg %r2,(__SF_GPRS+2*8)(%r15) + stg %r15,(__SF_GPRS+15*8)(%r15) lgr %r2,%r3 brasl %r14,ftrace_return_to_handler - aghi %r15,STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE + aghi %r15,STACK_FRAME_SIZE_FREGS lgr %r14,%r2 lmg %r2,%r5,32(%r15) BR_EX %r14 diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 1d7122a1883e..5fc3a2997977 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -228,7 +228,7 @@ config X86 select HAVE_GUP_FAST select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE select HAVE_FTRACE_MCOUNT_RECORD - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER + select HAVE_FUNCTION_GRAPH_FREGS if HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_GRAPH_TRACER if X86_32 || (X86_64 && DYNAMIC_FTRACE) select HAVE_FUNCTION_TRACER select HAVE_GCC_PLUGINS diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 78f6a200e15b..669771ef3b5b 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -64,6 +64,8 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) override_function_with_return(&(fregs)->regs) #define ftrace_regs_query_register_offset(name) \ regs_query_register_offset(name) +#define ftrace_regs_get_frame_pointer(fregs) \ + frame_pointer(&(fregs)->regs) struct ftrace_ops; #define ftrace_graph_func ftrace_graph_func @@ -148,24 +150,4 @@ static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) #endif /* !COMPILE_OFFSETS */ #endif /* !__ASSEMBLY__ */ -#ifndef __ASSEMBLY__ -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -struct fgraph_ret_regs { - unsigned long ax; - unsigned long dx; - unsigned long bp; -}; - -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->ax; -} - -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) -{ - return ret_regs->bp; -} -#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ -#endif - #endif /* _ASM_X86_FTRACE_H */ diff --git a/arch/x86/kernel/ftrace_32.S b/arch/x86/kernel/ftrace_32.S index 58d9ed50fe61..4b265884d06c 100644 --- a/arch/x86/kernel/ftrace_32.S +++ b/arch/x86/kernel/ftrace_32.S @@ -23,6 +23,8 @@ SYM_FUNC_START(__fentry__) SYM_FUNC_END(__fentry__) EXPORT_SYMBOL(__fentry__) +#define FRAME_SIZE PT_OLDSS+4 + SYM_CODE_START(ftrace_caller) #ifdef CONFIG_FRAME_POINTER @@ -187,14 +189,15 @@ SYM_CODE_END(ftrace_graph_caller) .globl return_to_handler return_to_handler: - pushl $0 - pushl %edx - pushl %eax + subl $(FRAME_SIZE), %esp + movl $0, PT_EBP(%esp) + movl %edx, PT_EDX(%esp) + movl %eax, PT_EAX(%esp) movl %esp, %eax call ftrace_return_to_handler movl %eax, %ecx - popl %eax - popl %edx - addl $4, %esp # skip ebp + movl %eax, PT_EAX(%esp) + movl %edx, PT_EDX(%esp) + addl $(FRAME_SIZE), %esp JMP_NOSPEC ecx #endif diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 214f30e9f0c0..d51647228596 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -348,21 +348,22 @@ STACK_FRAME_NON_STANDARD_FP(__fentry__) SYM_CODE_START(return_to_handler) UNWIND_HINT_UNDEFINED ANNOTATE_NOENDBR - subq $24, %rsp - /* Save the return values */ - movq %rax, (%rsp) - movq %rdx, 8(%rsp) - movq %rbp, 16(%rsp) + /* Save ftrace_regs for function exit context */ + subq $(FRAME_SIZE), %rsp + + movq %rax, RAX(%rsp) + movq %rdx, RDX(%rsp) + movq %rbp, RBP(%rsp) movq %rsp, %rdi call ftrace_return_to_handler movq %rax, %rdi - movq 8(%rsp), %rdx - movq (%rsp), %rax + movq RDX(%rsp), %rdx + movq RAX(%rsp), %rax - addq $24, %rsp + addq $(FRAME_SIZE), %rsp /* * Jump back to the old return address. This cannot be JMP_NOSPEC rdi * since IBT would demand that contain ENDBR, which simply isn't so for diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index dc2e8073aa79..9230af20c92e 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -43,9 +43,8 @@ struct dyn_ftrace; char *arch_ftrace_match_adjust(char *str, const char *search); -#ifdef CONFIG_HAVE_FUNCTION_GRAPH_RETVAL -struct fgraph_ret_regs; -unsigned long ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs); +#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FREGS +unsigned long ftrace_return_to_handler(struct ftrace_regs *fregs); #else unsigned long ftrace_return_to_handler(unsigned long frame_pointer); #endif @@ -134,6 +133,13 @@ extern int ftrace_enabled; * Also, architecture dependent fields can be used for internal process. * (e.g. orig_ax on x86_64) * + * Basically, ftrace_regs stores the registers related to the context. + * On function entry, registers for function parameters and hooking the + * function call are stored, and on function exit, registers for function + * return value and frame pointers are stored. + * + * And also, it dpends on the context that which registers are restored + * from the ftrace_regs. * On the function entry, those registers will be restored except for * the stack pointer, so that user can change the function parameters * and instruction pointer (e.g. live patching.) @@ -191,6 +197,8 @@ static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs) override_function_with_return(ftrace_get_regs(fregs)) #define ftrace_regs_query_register_offset(name) \ regs_query_register_offset(name) +#define ftrace_regs_get_frame_pointer(fregs) \ + frame_pointer(&(fregs)->regs) #endif typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 166ad5444eea..33fcfb36eca5 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -31,7 +31,7 @@ config HAVE_FUNCTION_GRAPH_TRACER help See Documentation/trace/ftrace-design.rst -config HAVE_FUNCTION_GRAPH_RETVAL +config HAVE_FUNCTION_GRAPH_FREGS bool config HAVE_DYNAMIC_FTRACE @@ -232,7 +232,7 @@ config FUNCTION_GRAPH_TRACER config FUNCTION_GRAPH_RETVAL bool "Kernel Function Graph Return Value" - depends on HAVE_FUNCTION_GRAPH_RETVAL + depends on HAVE_FUNCTION_GRAPH_FREGS depends on FUNCTION_GRAPH_TRACER default n help diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 269f10d02046..709f920da939 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -763,15 +763,12 @@ static struct notifier_block ftrace_suspend_notifier = { .notifier_call = ftrace_suspend_notifier_call, }; -/* fgraph_ret_regs is not defined without CONFIG_FUNCTION_GRAPH_RETVAL */ -struct fgraph_ret_regs; - /* * Send the trace to the ring-buffer. * @return the original return address. */ -static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs, - unsigned long frame_pointer) +static inline unsigned long +__ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointer) { struct ftrace_ret_stack *ret_stack; struct ftrace_graph_ret trace; @@ -791,7 +788,7 @@ static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs trace.rettime = trace_clock_local(); #ifdef CONFIG_FUNCTION_GRAPH_RETVAL - trace.retval = fgraph_ret_regs_return_value(ret_regs); + trace.retval = ftrace_regs_get_return_value(fregs); #endif bitmap = get_bitmap_bits(current, offset); @@ -826,14 +823,14 @@ static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs } /* - * After all architecures have selected HAVE_FUNCTION_GRAPH_RETVAL, we can - * leave only ftrace_return_to_handler(ret_regs). + * After all architecures have selected HAVE_FUNCTION_GRAPH_FREGS, we can + * leave only ftrace_return_to_handler(fregs). */ -#ifdef CONFIG_HAVE_FUNCTION_GRAPH_RETVAL -unsigned long ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs) +#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FREGS +unsigned long ftrace_return_to_handler(struct ftrace_regs *fregs) { - return __ftrace_return_to_handler(ret_regs, - fgraph_ret_regs_frame_pointer(ret_regs)); + return __ftrace_return_to_handler(fregs, + ftrace_regs_get_frame_pointer(fregs)); } #else unsigned long ftrace_return_to_handler(unsigned long frame_pointer) From patchwork Mon Jun 17 01:47:26 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699865 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 02B88160885; Mon, 17 Jun 2024 01:47:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588853; cv=none; b=G9ibBxtpkqxt6mRS4CV6PC1ZMmAMpUiTggiQrV8/HCPRxpuzOXmDt3N1VgAo0nkdIuGWePQvY3RQSnKQjjvZm0t+Ocgu+DnQD+2UwqCNZFVGXJV1cf9zJnRm2/GXFpdd6U2gEXCBrDYbc77oKdxtna/b4URh/aOVR8jBaU6bpho= ARC-Message-Signature: i=1; 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b=YBcdJHjsJ1VmjL3rJQEoE80iaST4IZn23J0uXG/OQ77ZEfyr8Inp3bw7JYslquHyD x+EC4XORoC/qc3hTs/3jPN+Xoukglgmfg9KL1ApOiF4ZzU6vV39VvMT4FODVjBHTIe WfSiKcMfUteoG1wkWt1gQNR2oO6rV2VobGM3PvahovKF3jUCgfJDP6pBHfxQpzMENw vp4vbvoYYyk55VChBbq2/Q9xKgmbFMwSq9b4C1dY86EEeicj6OvHmUyxcC6LwU3HuB tW9feCtJO7O9lr4e/JqWHw+iCzi1pUdS0Tkp2rIb0m1soK/SSiqFa/NXx4wjb1RUh6 a7r2ke4R+Cn1w== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 05/18] function_graph: Pass ftrace_regs to retfunc Date: Mon, 17 Jun 2024 10:47:26 +0900 Message-Id: <171858884638.288820.16050704329380001528.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Pass ftrace_regs to the fgraph_ops::retfunc(). If ftrace_regs is not available, it passes a NULL instead. User callback function can access some registers (including return address) via this ftrace_regs. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v8: - Pass ftrace_regs to retfunc, instead of adding retregfunc. Changes in v6: - update to use ftrace_regs_get_return_value() because of reordering patches. Changes in v3: - Update for new multiple fgraph. - Save the return address to instruction pointer in ftrace_regs. --- include/linux/ftrace.h | 3 ++- kernel/trace/fgraph.c | 16 +++++++++++----- kernel/trace/ftrace.c | 3 ++- kernel/trace/trace.h | 3 ++- kernel/trace/trace_functions_graph.c | 7 ++++--- kernel/trace/trace_irqsoff.c | 3 ++- kernel/trace/trace_sched_wakeup.c | 3 ++- kernel/trace/trace_selftest.c | 3 ++- 8 files changed, 27 insertions(+), 14 deletions(-) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 9230af20c92e..85394b9fb630 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -1069,7 +1069,8 @@ struct fgraph_ops; /* Type of the callback handlers for tracing function graph*/ typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *, - struct fgraph_ops *); /* return */ + struct fgraph_ops *, + struct ftrace_regs *); /* return */ typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *, struct fgraph_ops *, struct ftrace_regs *); /* entry */ diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 709f920da939..d735a8c872bb 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -297,7 +297,8 @@ static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops, } /* ftrace_graph_return set to this to tell some archs to run function graph */ -static void return_run(struct ftrace_graph_ret *trace, struct fgraph_ops *ops) +static void return_run(struct ftrace_graph_ret *trace, struct fgraph_ops *ops, + struct ftrace_regs *fregs) { } @@ -491,7 +492,8 @@ int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, } static void ftrace_graph_ret_stub(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { } @@ -787,6 +789,9 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe } trace.rettime = trace_clock_local(); + if (fregs) + ftrace_regs_set_instruction_pointer(fregs, ret); + #ifdef CONFIG_FUNCTION_GRAPH_RETVAL trace.retval = ftrace_regs_get_return_value(fregs); #endif @@ -796,7 +801,7 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe #ifdef CONFIG_HAVE_STATIC_CALL if (static_branch_likely(&fgraph_do_direct)) { if (test_bit(fgraph_direct_gops->idx, &bitmap)) - static_call(fgraph_retfunc)(&trace, fgraph_direct_gops); + static_call(fgraph_retfunc)(&trace, fgraph_direct_gops, fregs); } else #endif { @@ -806,7 +811,7 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe if (gops == &fgraph_stub) continue; - gops->retfunc(&trace, gops); + gops->retfunc(&trace, gops, fregs); } } @@ -956,7 +961,8 @@ void ftrace_graph_sleep_time_control(bool enable) * Simply points to ftrace_stub, but with the proper protocol. * Defined by the linker script in linux/vmlinux.lds.h */ -void ftrace_stub_graph(struct ftrace_graph_ret *trace, struct fgraph_ops *gops); +void ftrace_stub_graph(struct ftrace_graph_ret *trace, struct fgraph_ops *gops, + struct ftrace_regs *fregs); /* The callbacks that hook a function */ trace_func_graph_ret_t ftrace_graph_return = ftrace_stub_graph; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 64d15428cffc..725a95b161a1 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -840,7 +840,8 @@ static int profile_graph_entry(struct ftrace_graph_ent *trace, } static void profile_graph_return(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct ftrace_ret_stack *ret_stack; struct ftrace_profile_stat *stat; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 2b718e448026..75c97b0515da 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -682,7 +682,8 @@ void trace_latency_header(struct seq_file *m); void trace_default_header(struct seq_file *m); void print_trace_header(struct seq_file *m, struct trace_iterator *iter); -void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops); +void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops, + struct ftrace_regs *fregs); int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops, struct ftrace_regs *fregs); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index b9785fc919c9..241407000109 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -240,7 +240,7 @@ void __trace_graph_return(struct trace_array *tr, } void trace_graph_return(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, struct ftrace_regs *fregs) { unsigned long *task_var = fgraph_get_task_var(gops); struct trace_array *tr = gops->private; @@ -270,7 +270,8 @@ void trace_graph_return(struct ftrace_graph_ret *trace, } static void trace_graph_thresh_return(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { ftrace_graph_addr_finish(gops, trace); @@ -283,7 +284,7 @@ static void trace_graph_thresh_return(struct ftrace_graph_ret *trace, (trace->rettime - trace->calltime < tracing_thresh)) return; else - trace_graph_return(trace, gops); + trace_graph_return(trace, gops, fregs); } static struct fgraph_ops funcgraph_ops = { diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index ad739d76fc86..504de7a05498 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -208,7 +208,8 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace, } static void irqsoff_graph_return(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct trace_array *tr = irqsoff_trace; struct trace_array_cpu *data; diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 23360a2700de..9ffbd9326898 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -144,7 +144,8 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace, } static void wakeup_graph_return(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct trace_array *tr = wakeup_trace; struct trace_array_cpu *data; diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 92c16e99d4f2..d3c0c025dc1a 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -807,7 +807,8 @@ static __init int store_entry(struct ftrace_graph_ent *trace, } static __init void store_return(struct ftrace_graph_ret *trace, - struct fgraph_ops *gops) + struct fgraph_ops *gops, + struct ftrace_regs *fregs) { struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops); const char *type = fixture->store_type_name; From patchwork Mon Jun 17 01:47:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699866 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 710B1171E7F; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PtwfZYu5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1877AC2BBFC; Mon, 17 Jun 2024 01:47:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588863; bh=Oi3ERdr5cX4FnojsRR70VdCjSsUhPbMiCS4Fo3/dzhY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PtwfZYu5ZjlfUZAkpUkY594+5zFY3Q6Ap3f8vNLUjIHuyoirasPn6nzwYYyRjwjrH Up2seQOyST650M+lkNI3+qi7/MxId1R0k4HmPDto3syHL72VtV4LuxAj+sEqn8Xnkd hI9grOlp7N2C+aH1mI/HKPTlNVYLA9xDNuUt5g4lkpqE5tam2KMm+3OaBLwtqrEg52 1gX9JPmlZQA5Q+xVbZml8tkTwF7ErFGwhpWQi0USC0Ba0tAXRObYxEU4RcRMhh9/Em DYhxJK0e640RAcuGU2h3HZeiBspRB22ILoELQfvmzEJm+zZFZFSqDQG/WPTKTWuSG5 N3f55CJOw3l9A== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 06/18] fprobe: Use ftrace_regs in fprobe entry handler Date: Mon, 17 Jun 2024 10:47:38 +0900 Message-Id: <171858885796.288820.14034759303829161016.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Masami Hiramatsu (Google) This allows fprobes to be available with CONFIG_DYNAMIC_FTRACE_WITH_ARGS instead of CONFIG_DYNAMIC_FTRACE_WITH_REGS, then we can enable fprobe on arm64. Signed-off-by: Masami Hiramatsu (Google) Acked-by: Florent Revest --- Changes in v6: - Keep using SAVE_REGS flag to avoid breaking bpf kprobe-multi test. --- include/linux/fprobe.h | 2 +- kernel/trace/Kconfig | 3 ++- kernel/trace/bpf_trace.c | 10 +++++++--- kernel/trace/fprobe.c | 3 ++- kernel/trace/trace_fprobe.c | 6 +++++- lib/test_fprobe.c | 4 ++-- samples/fprobe/fprobe_example.c | 2 +- 7 files changed, 20 insertions(+), 10 deletions(-) diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index f39869588117..ca64ee5e45d2 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -10,7 +10,7 @@ struct fprobe; typedef int (*fprobe_entry_cb)(struct fprobe *fp, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *regs, void *entry_data); typedef void (*fprobe_exit_cb)(struct fprobe *fp, unsigned long entry_ip, diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 33fcfb36eca5..78b0da6fda1a 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -287,7 +287,7 @@ config DYNAMIC_FTRACE_WITH_ARGS config FPROBE bool "Kernel Function Probe (fprobe)" depends on FUNCTION_TRACER - depends on DYNAMIC_FTRACE_WITH_REGS + depends on DYNAMIC_FTRACE_WITH_REGS || DYNAMIC_FTRACE_WITH_ARGS depends on HAVE_RETHOOK select RETHOOK default n @@ -672,6 +672,7 @@ config FPROBE_EVENTS select TRACING select PROBE_EVENTS select DYNAMIC_EVENTS + depends on DYNAMIC_FTRACE_WITH_REGS default y help This allows user to add tracing events on the function entry and diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 6249dac61701..7e782a58ca6d 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2602,7 +2602,7 @@ struct bpf_session_run_ctx { void *data; }; -#ifdef CONFIG_FPROBE +#if defined(CONFIG_FPROBE) && defined(CONFIG_DYNAMIC_FTRACE_WITH_REGS) struct bpf_kprobe_multi_link { struct bpf_link link; struct fprobe fp; @@ -2854,12 +2854,16 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, static int kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *data) { + struct pt_regs *regs = ftrace_get_regs(fregs); struct bpf_kprobe_multi_link *link; int err; + if (!regs) + return 0; + link = container_of(fp, struct bpf_kprobe_multi_link, fp); err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, false, data); return is_kprobe_session(link->link.prog) ? err : 0; @@ -3134,7 +3138,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr kvfree(cookies); return err; } -#else /* !CONFIG_FPROBE */ +#else /* !CONFIG_FPROBE || !CONFIG_DYNAMIC_FTRACE_WITH_REGS */ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { return -EOPNOTSUPP; diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 9ff018245840..3d3789283873 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -46,7 +46,7 @@ static inline void __fprobe_handler(unsigned long ip, unsigned long parent_ip, } if (fp->entry_handler) - ret = fp->entry_handler(fp, ip, parent_ip, ftrace_get_regs(fregs), entry_data); + ret = fp->entry_handler(fp, ip, parent_ip, fregs, entry_data); /* If entry_handler returns !0, nmissed is not counted. */ if (rh) { @@ -182,6 +182,7 @@ static void fprobe_init(struct fprobe *fp) fp->ops.func = fprobe_kprobe_handler; else fp->ops.func = fprobe_handler; + fp->ops.flags |= FTRACE_OPS_FL_SAVE_REGS; } diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 62e6a8f4aae9..b2c20d4fdfd7 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -338,12 +338,16 @@ NOKPROBE_SYMBOL(fexit_perf_func); #endif /* CONFIG_PERF_EVENTS */ static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data) { struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); + struct pt_regs *regs = ftrace_get_regs(fregs); int ret = 0; + if (!regs) + return 0; + if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) fentry_trace_func(tf, entry_ip, regs); #ifdef CONFIG_PERF_EVENTS diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c index 24de0e5ff859..ff607babba18 100644 --- a/lib/test_fprobe.c +++ b/lib/test_fprobe.c @@ -40,7 +40,7 @@ static noinline u32 fprobe_selftest_nest_target(u32 value, u32 (*nest)(u32)) static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, - struct pt_regs *regs, void *data) + struct ftrace_regs *fregs, void *data) { KUNIT_EXPECT_FALSE(current_test, preemptible()); /* This can be called on the fprobe_selftest_target and the fprobe_selftest_target2 */ @@ -81,7 +81,7 @@ static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, static notrace int nest_entry_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, - struct pt_regs *regs, void *data) + struct ftrace_regs *fregs, void *data) { KUNIT_EXPECT_FALSE(current_test, preemptible()); return 0; diff --git a/samples/fprobe/fprobe_example.c b/samples/fprobe/fprobe_example.c index 64e715e7ed11..1545a1aac616 100644 --- a/samples/fprobe/fprobe_example.c +++ b/samples/fprobe/fprobe_example.c @@ -50,7 +50,7 @@ static void show_backtrace(void) static int sample_entry_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, - struct pt_regs *regs, void *data) + struct ftrace_regs *fregs, void *data) { if (use_trace) /* From patchwork Mon Jun 17 01:47:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699867 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E593F17B412; Mon, 17 Jun 2024 01:47:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; 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Mon, 17 Jun 2024 01:47:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588875; bh=1FrPZiLi+oXKtlCx0K0OWgBz8gkLIGLv65VzE2gjtSk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P245FY1w3ZJlN4EHhzRxKHUs2X1krkhb8usaymtMEajTCHgDgD5POA6VHxxNkRSk0 CsBMc41MpPNxA/bePIycnnOhTpaEEn4vjsfMFO/2CtJYlyLFoHFX7PgWyNZ2l4Lp2e /ojv4S3vFYcGATRerLYztoiYGJ6k2H+ARNYojGAy4HymGpVCATYocXaXOzk7owwjVB Gka2/8rdWhsmCaNha5ASzB6vHwvjnW/WZjc7Ma5owbsojAUiC+ej2d7zmxqhEOY+m5 U61Th30e23t83Bgk/k8PpAF6D5mkWHWartWPzSpD1WkP3DIqXL1ahwTXtK5artXxbh W8WihzbPbS50A== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 07/18] fprobe: Use ftrace_regs in fprobe exit handler Date: Mon, 17 Jun 2024 10:47:49 +0900 Message-Id: <171858886932.288820.10097034823222475640.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Masami Hiramatsu (Google) Change the fprobe exit handler to use ftrace_regs structure instead of pt_regs. This also introduce HAVE_PT_REGS_TO_FTRACE_REGS_CAST which means the ftrace_regs's memory layout is equal to the pt_regs so that those are able to cast. Fprobe introduces a new dependency with that. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v3: - Use ftrace_regs_get_return_value() Changes from previous series: NOTHING, just forward ported. --- arch/loongarch/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/x86/Kconfig | 1 + include/linux/fprobe.h | 2 +- include/linux/ftrace.h | 6 ++++++ kernel/trace/Kconfig | 8 ++++++++ kernel/trace/bpf_trace.c | 6 +++++- kernel/trace/fprobe.c | 3 ++- kernel/trace/trace_fprobe.c | 6 +++++- lib/test_fprobe.c | 6 +++--- samples/fprobe/fprobe_example.c | 2 +- 11 files changed, 34 insertions(+), 8 deletions(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 23014d5f0047..0f1b2057507b 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -119,6 +119,7 @@ config LOONGARCH select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_ARGS + select HAVE_PT_REGS_TO_FTRACE_REGS_CAST select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_EBPF_JIT diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 33688d43fd14..adc8f6620525 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -173,6 +173,7 @@ config S390 select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_ARGS + select HAVE_PT_REGS_TO_FTRACE_REGS_CAST select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 5fc3a2997977..d4655b72e6d7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -218,6 +218,7 @@ config X86 select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64 + select HAVE_PT_REGS_TO_FTRACE_REGS_CAST if X86_64 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_SAMPLE_FTRACE_DIRECT if X86_64 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if X86_64 diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index ca64ee5e45d2..ef609bcca0f9 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -14,7 +14,7 @@ typedef int (*fprobe_entry_cb)(struct fprobe *fp, unsigned long entry_ip, void *entry_data); typedef void (*fprobe_exit_cb)(struct fprobe *fp, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *regs, void *entry_data); /** diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 85394b9fb630..fa578748f7d2 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -162,6 +162,12 @@ struct ftrace_regs { #define ftrace_regs_set_instruction_pointer(fregs, ip) do { } while (0) #endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ +#ifdef CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST + +static_assert(sizeof(struct pt_regs) == sizeof(struct ftrace_regs)); + +#endif /* CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST */ + static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs) { if (!fregs) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 78b0da6fda1a..15e340a865f5 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -57,6 +57,13 @@ config HAVE_DYNAMIC_FTRACE_WITH_ARGS This allows for use of ftrace_regs_get_argument() and ftrace_regs_get_stack_pointer(). +config HAVE_PT_REGS_TO_FTRACE_REGS_CAST + bool + help + If this is set, the memory layout of the ftrace_regs data structure + is the same as the pt_regs. So the pt_regs is possible to be casted + to ftrace_regs. + config HAVE_DYNAMIC_FTRACE_NO_PATCHABLE bool help @@ -288,6 +295,7 @@ config FPROBE bool "Kernel Function Probe (fprobe)" depends on FUNCTION_TRACER depends on DYNAMIC_FTRACE_WITH_REGS || DYNAMIC_FTRACE_WITH_ARGS + depends on HAVE_PT_REGS_TO_FTRACE_REGS_CAST || !HAVE_DYNAMIC_FTRACE_WITH_ARGS depends on HAVE_RETHOOK select RETHOOK default n diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 7e782a58ca6d..f72b421abe9b 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2871,10 +2871,14 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, static void kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *data) { struct bpf_kprobe_multi_link *link; + struct pt_regs *regs = ftrace_get_regs(fregs); + + if (!regs) + return; link = container_of(fp, struct bpf_kprobe_multi_link, fp); kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, true, data); diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 3d3789283873..90a3c8e2bbdf 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -124,6 +124,7 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, { struct fprobe *fp = (struct fprobe *)data; struct fprobe_rethook_node *fpr; + struct ftrace_regs *fregs = (struct ftrace_regs *)regs; int bit; if (!fp || fprobe_disabled(fp)) @@ -141,7 +142,7 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, return; } - fp->exit_handler(fp, fpr->entry_ip, ret_ip, regs, + fp->exit_handler(fp, fpr->entry_ip, ret_ip, fregs, fp->entry_data_size ? (void *)fpr->data : NULL); ftrace_test_recursion_unlock(bit); } diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index b2c20d4fdfd7..273cdf3cf70c 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -359,10 +359,14 @@ static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip, NOKPROBE_SYMBOL(fentry_dispatcher); static void fexit_dispatcher(struct fprobe *fp, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data) { struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); + struct pt_regs *regs = ftrace_get_regs(fregs); + + if (!regs) + return; if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) fexit_trace_func(tf, entry_ip, ret_ip, regs, entry_data); diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c index ff607babba18..271ce0caeec0 100644 --- a/lib/test_fprobe.c +++ b/lib/test_fprobe.c @@ -59,9 +59,9 @@ static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip, static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, - struct pt_regs *regs, void *data) + struct ftrace_regs *fregs, void *data) { - unsigned long ret = regs_return_value(regs); + unsigned long ret = ftrace_regs_get_return_value(fregs); KUNIT_EXPECT_FALSE(current_test, preemptible()); if (ip != target_ip) { @@ -89,7 +89,7 @@ static notrace int nest_entry_handler(struct fprobe *fp, unsigned long ip, static notrace void nest_exit_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, - struct pt_regs *regs, void *data) + struct ftrace_regs *fregs, void *data) { KUNIT_EXPECT_FALSE(current_test, preemptible()); KUNIT_EXPECT_EQ(current_test, ip, target_nest_ip); diff --git a/samples/fprobe/fprobe_example.c b/samples/fprobe/fprobe_example.c index 1545a1aac616..d476d1f07538 100644 --- a/samples/fprobe/fprobe_example.c +++ b/samples/fprobe/fprobe_example.c @@ -67,7 +67,7 @@ static int sample_entry_handler(struct fprobe *fp, unsigned long ip, } static void sample_exit_handler(struct fprobe *fp, unsigned long ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *regs, void *data) { unsigned long rip = ret_ip; From patchwork Mon Jun 17 01:48:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699868 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D0AE1160884; Mon, 17 Jun 2024 01:48:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588887; cv=none; b=c3srDuAcFEwEMS7Qz4S4CIJztz4gLTALqye/bzXANXGBbvQBF0vAafL8CGEU/1FOp+ktMYwwgG6Nu4oDfHZv5NsVmR0agh4lPnGXnBlDwKelxV0to2Fc6ax6ze5dCbJuVhnDB8Za58yZ5U0z3Yi2rtZjAFE9fbjJPddApdJ7ZX0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588887; c=relaxed/simple; bh=v+ndCkQC6hxxweJTYXdlfbViE3auXeHXe5Z/+0ut9Lo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=kJx106dQtZzQeZu0Dk5uewpS0hMM3FQJITf2FCYeKj77PjYcvN0v2cXWUo/ArXiocQDU03Xk0HtDPckuRC5V7gJNyInNbAZlJMn754iBruUOszELhKEBmkk3Xe0t9DIBdzk/yx9RdAGNvVOW4XvQV1DTm9fgwRZ+QEx0tkZ1a/I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HNDHGKDz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HNDHGKDz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9F4E3C2BBFC; Mon, 17 Jun 2024 01:48:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588887; bh=v+ndCkQC6hxxweJTYXdlfbViE3auXeHXe5Z/+0ut9Lo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HNDHGKDzy6rd3s+qEqA0235h9i07HSM9SPUjS6hwOod4+rQdDpudjsziDNqe5nGWR YrF+AmrsG5nE9rnvypi+X6mVqVOMDfehbf2uJOTdUWfgQtaj3GiWSuEvoEYV3u0P1/ UCMX1pJEK8w61jwQM/jd08m16X4r8rpZtL4JB2rNWwCvXLHVb8VWeEYrEsP6nXymrI f2kujOX2b+4asY4YPRoFsfaJ+Vkk287lk4UWuqKUDFB4hljVrnO59tFOZAQ94eGBOq FJLtPSpoL3i2Hq/MHSA73MN+mDTNOlwueSBGgZk+eTCjNFIZPvSpA83Cnwg8M0ALqI +LV+d5w35QBjA== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 08/18] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs Date: Mon, 17 Jun 2024 10:48:00 +0900 Message-Id: <171858888079.288820.8680496982210564353.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Add ftrace_partial_regs() which converts the ftrace_regs to pt_regs. This is for the eBPF which needs this to keep the same pt_regs interface to access registers. Thus when replacing the pt_regs with ftrace_regs in fprobes (which is used by kprobe_multi eBPF event), this will be used. If the architecture defines its own ftrace_regs, this copies partial registers to pt_regs and returns it. If not, ftrace_regs is the same as pt_regs and ftrace_partial_regs() will return ftrace_regs::regs. Signed-off-by: Masami Hiramatsu (Google) Acked-by: Florent Revest --- Changes in v8: - Add the reason why this required in changelog. Changes from previous series: NOTHING, just forward ported. --- arch/arm64/include/asm/ftrace.h | 11 +++++++++++ include/linux/ftrace.h | 17 +++++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index dffaab3dd1f1..5cd587afab6d 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -132,6 +132,17 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) return fregs->fp; } +static __always_inline struct pt_regs * +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) +{ + memcpy(regs->regs, fregs->regs, sizeof(u64) * 9); + regs->sp = fregs->sp; + regs->pc = fregs->pc; + regs->regs[29] = fregs->fp; + regs->regs[30] = fregs->lr; + return regs; +} + int ftrace_regs_query_register_offset(const char *name); int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index fa578748f7d2..8e5da4dfb669 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -176,6 +176,23 @@ static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs return arch_ftrace_get_regs(fregs); } +#if !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) || \ + defined(CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST) + +static __always_inline struct pt_regs * +ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + /* + * If CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST=y, ftrace_regs memory + * layout is the same as pt_regs. So always returns that address. + * Since arch_ftrace_get_regs() will check some members and may return + * NULL, we can not use it. + */ + return &fregs->regs; +} + +#endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST */ + /* * When true, the ftrace_regs_{get,set}_*() functions may be used on fregs. * Note: this can be true even when ftrace_get_regs() cannot provide a pt_regs. From patchwork Mon Jun 17 01:48:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699869 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D9649167DB7; Mon, 17 Jun 2024 01:48:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588899; cv=none; b=dZgFZGsCAAdXrcCavP4pqKihFIiKuZ5NTs/b+1a2Rs4cItZWdNIIu3KTrG3pnoBncU5UX3bnlPNDgHgWx4LWiqWPqwXi0F8HBhhdBUxumZTtvVQvlFNWxHzOPijCK1yv6jVqqGLUKkjB0vG8rnZsxwFQr1Pj5ttEsyD26xXhfOA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588899; c=relaxed/simple; bh=/VkGokuIcVcQano3dTMPV/ivHT7rHLNTBlAmf8sfb3Y=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=jJDdlQNmsttTpVvqh6IDOnLqadMOpRHyNFeXIOK1rn4VbashTJGbtgwvIgDYRBCBlxod0ac0No1K70aObe5iN6azN6AgxQvt0ri3QVaiy1C/Wbrkgn8TkPsZTpMPylBUpxAYhYwnM37QV4CYw5ZbHP6ljn4sTPcnE1LQoKDZigI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tap0EcsD; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tap0EcsD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04F8FC2BBFC; Mon, 17 Jun 2024 01:48:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588898; bh=/VkGokuIcVcQano3dTMPV/ivHT7rHLNTBlAmf8sfb3Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tap0EcsDxzW6rXzgpgPqIVFMXiplZDNb8VHlChLa58w5nsOQNTSIBGT7LMwkx+5zH 0na9teoBPemYPXSzccq06ZKqONjwn1TqRyps5+qiNUHMIrLY5ogpIvCGy1xClBeq/k B8vkwFCdAIfGT/We2zehmj4P2I/HCstxUpjysJlIub7VkOn6Wu8bjaYxFkLqnKqThl dK+tHjc9pDi0jJ26lDThfw9smf0ISVn3T/wuQd9hkxS3YDRzLSYVsM4EACfNexU3kc J+yC0b978vJK8ZTEcBK2ZEYuHmh9xnlNJnSZP/NgXBpXjmW1PxzWAVtSMWVme7w0n1 /xYW5TihjhjcQ== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 09/18] tracing: Add ftrace_fill_perf_regs() for perf event Date: Mon, 17 Jun 2024 10:48:12 +0900 Message-Id: <171858889277.288820.10529133402471636736.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Add ftrace_fill_perf_regs() which should be compatible with the perf_fetch_caller_regs(). In other words, the pt_regs returned from the ftrace_fill_perf_regs() must satisfy 'user_mode(regs) == false' and can be used for stack tracing. Signed-off-by: Masami Hiramatsu (Google) --- Changes from previous series: NOTHING, just forward ported. --- arch/arm64/include/asm/ftrace.h | 7 +++++++ arch/powerpc/include/asm/ftrace.h | 7 +++++++ arch/s390/include/asm/ftrace.h | 5 +++++ arch/x86/include/asm/ftrace.h | 7 +++++++ include/linux/ftrace.h | 31 +++++++++++++++++++++++++++++++ 5 files changed, 57 insertions(+) diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index 5cd587afab6d..14ecb9a418d9 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -143,6 +143,13 @@ ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) return regs; } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->pc = (fregs)->pc; \ + (_regs)->regs[29] = (fregs)->fp; \ + (_regs)->sp = (fregs)->sp; \ + (_regs)->pstate = PSR_MODE_EL1h; \ + } while (0) + int ftrace_regs_query_register_offset(const char *name); int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index 23d26f3afae4..e6ff6834bf7e 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -42,6 +42,13 @@ static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs * return fregs->regs.msr ? &fregs->regs : NULL; } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->result = 0; \ + (_regs)->nip = (fregs)->regs.nip; \ + (_regs)->gpr[1] = (fregs)->regs.gpr[1]; \ + asm volatile("mfmsr %0" : "=r" ((_regs)->msr)); \ + } while (0) + static __always_inline void ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 9cdd48a46bf7..0d9f6df21f81 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -84,6 +84,11 @@ ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs) return sp[0]; /* return backchain */ } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->psw.addr = (fregs)->regs.psw.addr; \ + (_regs)->gprs[15] = (fregs)->regs.gprs[15]; \ + } while (0) + #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS /* * When an ftrace registered caller is tracing a function that is diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 669771ef3b5b..1f4d1f7b19ed 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -46,6 +46,13 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) return &fregs->regs; } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->ip = (fregs)->regs.ip; \ + (_regs)->sp = (fregs)->regs.sp; \ + (_regs)->cs = __KERNEL_CS; \ + (_regs)->flags = 0; \ + } while (0) + #define ftrace_regs_set_instruction_pointer(fregs, _ip) \ do { (fregs)->regs.ip = (_ip); } while (0) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 8e5da4dfb669..d9a3723f987d 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -193,6 +193,37 @@ ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) #endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST */ +#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS + +/* + * Please define arch dependent pt_regs which compatible to the + * perf_arch_fetch_caller_regs() but based on ftrace_regs. + * This requires + * - user_mode(_regs) returns false (always kernel mode). + * - able to use the _regs for stack trace. + */ +#ifndef arch_ftrace_fill_perf_regs +/* As same as perf_arch_fetch_caller_regs(), do nothing by default */ +#define arch_ftrace_fill_perf_regs(fregs, _regs) do {} while (0) +#endif + +static __always_inline struct pt_regs * +ftrace_fill_perf_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + arch_ftrace_fill_perf_regs(fregs, regs); + return regs; +} + +#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ + +static __always_inline struct pt_regs * +ftrace_fill_perf_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + return &fregs->regs; +} + +#endif + /* * When true, the ftrace_regs_{get,set}_*() functions may be used on fregs. * Note: this can be true even when ftrace_get_regs() cannot provide a pt_regs. From patchwork Mon Jun 17 01:48:24 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699870 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ADCC0176AC6; Mon, 17 Jun 2024 01:48:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588911; cv=none; b=V9iU0W7aCMyMv4/zycN7KcJedZwvA2WwzICJAtwutiGFcIG+mwpMQSFLqIyMKMaYThEaOWGi2U0eQj0hgiZWF+2ZEZ+YhtLyGSF2wiu08FxM0fKiYKnnvM6LkwiUD+j+s/bBpe0cmCmYrY3ia9NR7Iq6f6tSL5D+YmqVp5XmG6M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588911; c=relaxed/simple; bh=W2sxVfn7IPRly39KUuTI3UsMfFJ+1s5c6woRYmLQ7og=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=cbMTAxY6TQJh4ocuIyoFOnqbRKzFobZPmM5S0kU0yPHedIuNA8f8YNT0o+y0N0ATkN+E5YoRZZs2jbWYIKDbaVvpWbZP+f5mdFE9QbcZVqWfW7dtjZ5TmRzg0t4YXzgfuzYE3WXSxa3Uz68fXhxq5+T4SjFtYT+YQhSjLV1Vo3E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OlVTgC4O; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OlVTgC4O" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E68EC2BBFC; Mon, 17 Jun 2024 01:48:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588910; bh=W2sxVfn7IPRly39KUuTI3UsMfFJ+1s5c6woRYmLQ7og=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OlVTgC4OT/0yWVxzGqLyfB+tpbXye+dKOK1kD6gsLaQrszZTqQrapjLQr7I4Fw0Op Wdu9Rz4xcubZrVfDAvyvhasOkOViUQTZddvjg1LNLHfq77AU/rJRzYcVPhj/qegEjq EwAdWMuAecBw9SSZExmozHeUj84JdEubROOxMe1ysN4Fqe1YYMwoT4fZRj5nklA0+D 0MYSfblBkR716KpKlJM/8MDyobOJQ/8E8Q07gxOtcANyQO9rK+wsQ/Kv+hPpQlsaQ+ NkynO3kCxMcI/mMRTWthY5kKoT9K06eO3IXt23rtZW5SZ2qZCihaQRCUAWr72F2DY6 M3aMwz8EIhmCw== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 10/18] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Date: Mon, 17 Jun 2024 10:48:24 +0900 Message-Id: <171858890414.288820.7976290340572368092.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Allow fprobe events to be enabled with CONFIG_DYNAMIC_FTRACE_WITH_ARGS. With this change, fprobe events mostly use ftrace_regs instead of pt_regs. Note that if the arch doesn't enable HAVE_PT_REGS_COMPAT_FTRACE_REGS, fprobe events will not be able to be used from perf. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v9: - Copy store_trace_entry_data() as store_fprobe_entry_data() for fprobe. Chagnes in v3: - Use ftrace_regs_get_return_value(). Changes in v2: - Define ftrace_regs_get_kernel_stack_nth() for !CONFIG_HAVE_REGS_AND_STACK_ACCESS_API. Changes from previous series: Update against the new series. --- include/linux/ftrace.h | 17 ++++++ kernel/trace/Kconfig | 1 kernel/trace/trace_fprobe.c | 107 +++++++++++++++++++++++++-------------- kernel/trace/trace_probe_tmpl.h | 2 - 4 files changed, 86 insertions(+), 41 deletions(-) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index d9a3723f987d..d8a58b940d81 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -255,6 +255,23 @@ static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs) frame_pointer(&(fregs)->regs) #endif +#ifdef CONFIG_HAVE_REGS_AND_STACK_ACCESS_API +static __always_inline unsigned long +ftrace_regs_get_kernel_stack_nth(struct ftrace_regs *fregs, unsigned int nth) +{ + unsigned long *stackp; + + stackp = (unsigned long *)ftrace_regs_get_stack_pointer(fregs); + if (((unsigned long)(stackp + nth) & ~(THREAD_SIZE - 1)) == + ((unsigned long)stackp & ~(THREAD_SIZE - 1))) + return *(stackp + nth); + + return 0; +} +#else /* !CONFIG_HAVE_REGS_AND_STACK_ACCESS_API */ +#define ftrace_regs_get_kernel_stack_nth(fregs, nth) (0L) +#endif /* CONFIG_HAVE_REGS_AND_STACK_ACCESS_API */ + typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 15e340a865f5..4a3dd81f749b 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -680,7 +680,6 @@ config FPROBE_EVENTS select TRACING select PROBE_EVENTS select DYNAMIC_EVENTS - depends on DYNAMIC_FTRACE_WITH_REGS default y help This allows user to add tracing events on the function entry and diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 273cdf3cf70c..86cd6a8c806a 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -133,7 +133,7 @@ static int process_fetch_insn(struct fetch_insn *code, void *rec, void *edata, void *dest, void *base) { - struct pt_regs *regs = rec; + struct ftrace_regs *fregs = rec; unsigned long val; int ret; @@ -141,17 +141,17 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *edata, /* 1st stage: get value from context */ switch (code->op) { case FETCH_OP_STACK: - val = regs_get_kernel_stack_nth(regs, code->param); + val = ftrace_regs_get_kernel_stack_nth(fregs, code->param); break; case FETCH_OP_STACKP: - val = kernel_stack_pointer(regs); + val = ftrace_regs_get_stack_pointer(fregs); break; case FETCH_OP_RETVAL: - val = regs_return_value(regs); + val = ftrace_regs_get_return_value(fregs); break; #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API case FETCH_OP_ARG: - val = regs_get_kernel_argument(regs, code->param); + val = ftrace_regs_get_argument(fregs, code->param); break; case FETCH_OP_EDATA: val = *(unsigned long *)((unsigned long)edata + code->offset); @@ -174,7 +174,7 @@ NOKPROBE_SYMBOL(process_fetch_insn) /* function entry handler */ static nokprobe_inline void __fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - struct pt_regs *regs, + struct ftrace_regs *fregs, struct trace_event_file *trace_file) { struct fentry_trace_entry_head *entry; @@ -188,41 +188,71 @@ __fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, if (trace_trigger_soft_disabled(trace_file)) return; - dsize = __get_data_size(&tf->tp, regs, NULL); + dsize = __get_data_size(&tf->tp, fregs, NULL); entry = trace_event_buffer_reserve(&fbuffer, trace_file, sizeof(*entry) + tf->tp.size + dsize); if (!entry) return; - fbuffer.regs = regs; + fbuffer.regs = ftrace_get_regs(fregs); entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); entry->ip = entry_ip; - store_trace_args(&entry[1], &tf->tp, regs, NULL, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, NULL, sizeof(*entry), dsize); trace_event_buffer_commit(&fbuffer); } static void fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - struct pt_regs *regs) + struct ftrace_regs *fregs) { struct event_file_link *link; trace_probe_for_each_link_rcu(link, &tf->tp) - __fentry_trace_func(tf, entry_ip, regs, link->file); + __fentry_trace_func(tf, entry_ip, fregs, link->file); } NOKPROBE_SYMBOL(fentry_trace_func); +static nokprobe_inline +void store_fprobe_entry_data(void *edata, struct trace_probe *tp, struct ftrace_regs *fregs) +{ + struct probe_entry_arg *earg = tp->entry_arg; + unsigned long val = 0; + int i; + + if (!earg) + return; + + for (i = 0; i < earg->size; i++) { + struct fetch_insn *code = &earg->code[i]; + + switch (code->op) { + case FETCH_OP_ARG: + val = ftrace_regs_get_argument(fregs, code->param); + break; + case FETCH_OP_ST_EDATA: + *(unsigned long *)((unsigned long)edata + code->offset) = val; + break; + case FETCH_OP_END: + goto end; + default: + break; + } + } +end: + return; +} + /* function exit handler */ static int trace_fprobe_entry_handler(struct fprobe *fp, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data) { struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); if (tf->tp.entry_arg) - store_trace_entry_data(entry_data, &tf->tp, regs); + store_fprobe_entry_data(entry_data, &tf->tp, fregs); return 0; } @@ -230,7 +260,7 @@ NOKPROBE_SYMBOL(trace_fprobe_entry_handler) static nokprobe_inline void __fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data, struct trace_event_file *trace_file) { struct fexit_trace_entry_head *entry; @@ -244,60 +274,63 @@ __fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, if (trace_trigger_soft_disabled(trace_file)) return; - dsize = __get_data_size(&tf->tp, regs, entry_data); + dsize = __get_data_size(&tf->tp, fregs, entry_data); entry = trace_event_buffer_reserve(&fbuffer, trace_file, sizeof(*entry) + tf->tp.size + dsize); if (!entry) return; - fbuffer.regs = regs; + fbuffer.regs = ftrace_get_regs(fregs); entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); entry->func = entry_ip; entry->ret_ip = ret_ip; - store_trace_args(&entry[1], &tf->tp, regs, entry_data, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, entry_data, sizeof(*entry), dsize); trace_event_buffer_commit(&fbuffer); } static void fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, void *entry_data) + unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data) { struct event_file_link *link; trace_probe_for_each_link_rcu(link, &tf->tp) - __fexit_trace_func(tf, entry_ip, ret_ip, regs, entry_data, link->file); + __fexit_trace_func(tf, entry_ip, ret_ip, fregs, entry_data, link->file); } NOKPROBE_SYMBOL(fexit_trace_func); #ifdef CONFIG_PERF_EVENTS static int fentry_perf_func(struct trace_fprobe *tf, unsigned long entry_ip, - struct pt_regs *regs) + struct ftrace_regs *fregs) { struct trace_event_call *call = trace_probe_event_call(&tf->tp); struct fentry_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; + struct pt_regs *regs; int rctx; head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) return 0; - dsize = __get_data_size(&tf->tp, regs, NULL); + dsize = __get_data_size(&tf->tp, fregs, NULL); __size = sizeof(*entry) + tf->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - entry = perf_trace_buf_alloc(size, NULL, &rctx); + entry = perf_trace_buf_alloc(size, ®s, &rctx); if (!entry) return 0; + regs = ftrace_fill_perf_regs(fregs, regs); + entry->ip = entry_ip; memset(&entry[1], 0, dsize); - store_trace_args(&entry[1], &tf->tp, regs, NULL, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, NULL, sizeof(*entry), dsize); perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, head, NULL); return 0; @@ -306,31 +339,34 @@ NOKPROBE_SYMBOL(fentry_perf_func); static void fexit_perf_func(struct trace_fprobe *tf, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data) { struct trace_event_call *call = trace_probe_event_call(&tf->tp); struct fexit_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; + struct pt_regs *regs; int rctx; head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) return; - dsize = __get_data_size(&tf->tp, regs, entry_data); + dsize = __get_data_size(&tf->tp, fregs, entry_data); __size = sizeof(*entry) + tf->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - entry = perf_trace_buf_alloc(size, NULL, &rctx); + entry = perf_trace_buf_alloc(size, ®s, &rctx); if (!entry) return; + regs = ftrace_fill_perf_regs(fregs, regs); + entry->func = entry_ip; entry->ret_ip = ret_ip; - store_trace_args(&entry[1], &tf->tp, regs, entry_data, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, entry_data, sizeof(*entry), dsize); perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, head, NULL); } @@ -342,17 +378,14 @@ static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip, void *entry_data) { struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); - struct pt_regs *regs = ftrace_get_regs(fregs); int ret = 0; - if (!regs) - return 0; - if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) - fentry_trace_func(tf, entry_ip, regs); + fentry_trace_func(tf, entry_ip, fregs); + #ifdef CONFIG_PERF_EVENTS if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE)) - ret = fentry_perf_func(tf, entry_ip, regs); + ret = fentry_perf_func(tf, entry_ip, fregs); #endif return ret; } @@ -363,16 +396,12 @@ static void fexit_dispatcher(struct fprobe *fp, unsigned long entry_ip, void *entry_data) { struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); - struct pt_regs *regs = ftrace_get_regs(fregs); - - if (!regs) - return; if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) - fexit_trace_func(tf, entry_ip, ret_ip, regs, entry_data); + fexit_trace_func(tf, entry_ip, ret_ip, fregs, entry_data); #ifdef CONFIG_PERF_EVENTS if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE)) - fexit_perf_func(tf, entry_ip, ret_ip, regs, entry_data); + fexit_perf_func(tf, entry_ip, ret_ip, fregs, entry_data); #endif } NOKPROBE_SYMBOL(fexit_dispatcher); diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h index 2caf0d2afb32..f39b37fcdb3b 100644 --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -232,7 +232,7 @@ process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val, /* Sum up total data length for dynamic arrays (strings) */ static nokprobe_inline int -__get_data_size(struct trace_probe *tp, struct pt_regs *regs, void *edata) +__get_data_size(struct trace_probe *tp, void *regs, void *edata) { struct probe_arg *arg; int i, len, ret = 0; From patchwork Mon Jun 17 01:48:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699871 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 26F4617B405; Mon, 17 Jun 2024 01:48:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588922; cv=none; b=JZFEMaB4Bkcl2S/okf8AEtMP0NQ8ZDAZGCKzZQ3uvbSNeA4NX/FudzwHMw358AlbngdtA4meOFBTu+cojYs7XYNvv/aF7+CtIOlq5nq12oBC0wEjys+f6SLjzut8mG0VJn+55SvB/7/Z9i1dV6f6PpAirCcs0cT4sz1dhVg1RAI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588922; c=relaxed/simple; bh=OtlEX+N2t22ZO0stHC9uK5V+uqtQ/aaFzUaCS8qHyPs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=K8kepG2l0RNBF6rtnUYX4BFawnn/gJYd4NHbPE1R9IN4Jhjid/XyzMgJwnhy/sxsdt9ep6ZRkymx6YhYNDCZlhGsmZiAbDKR5e4eob3xUYlLbwRNh21b1NdEtRCKCcWs7CmpYSyKWWQHGrP//zsmbaial1GR1VlohOiLgDa9FIQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pyDsqC97; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pyDsqC97" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0935C2BBFC; Mon, 17 Jun 2024 01:48:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588921; bh=OtlEX+N2t22ZO0stHC9uK5V+uqtQ/aaFzUaCS8qHyPs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pyDsqC97kz1mka8vfaJ3GfreR49Tmq3oIi84RUy/CYDIUkyFQWgdAkme+PQZK5bQf KdiS9lLFtqr7jhfLv8TjQPzb0dLzQEm4ZapiMhydanYIpaorcF4YgWNbUqQ9ZkxHSw lkNQyvvxHWr/lum07/T0/eOV24BmuopJxvdDfLtkxmwIlyAkxfJKDaSQsSikU6U0Lt 0cztTRQterBv/2741/4tJwlaTPhauoivCDOzYZc5E5AnaRtb39PngZGy1hgzDx7T3a zReXqQLzqMfq28UwMjom5CcG/7xqXZ4UFadhbJDt57Si9ktuDpCNP2mhAeWX2+Y9EU 3ZYIlBWbcuwgw== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 11/18] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled Date: Mon, 17 Jun 2024 10:48:35 +0900 Message-Id: <171858891561.288820.4872201300777607443.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Masami Hiramatsu (Google) Enable kprobe_multi feature if CONFIG_FPROBE is enabled. The pt_regs is converted from ftrace_regs by ftrace_partial_regs(), thus some registers may always returns 0. But it should be enough for function entry (access arguments) and exit (access return value). Signed-off-by: Masami Hiramatsu (Google) Acked-by: Florent Revest --- Changes in v9: - Avoid wasting memory for bpf_kprobe_multi_pt_regs when CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST=y --- kernel/trace/bpf_trace.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index f72b421abe9b..77fd63027286 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2602,7 +2602,7 @@ struct bpf_session_run_ctx { void *data; }; -#if defined(CONFIG_FPROBE) && defined(CONFIG_DYNAMIC_FTRACE_WITH_REGS) +#ifdef CONFIG_FPROBE struct bpf_kprobe_multi_link { struct bpf_link link; struct fprobe fp; @@ -2625,6 +2625,13 @@ struct user_syms { char *buf; }; +#ifndef CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST +static DEFINE_PER_CPU(struct pt_regs, bpf_kprobe_multi_pt_regs); +#define bpf_kprobe_multi_pt_regs_ptr() this_cpu_ptr(&bpf_kprobe_multi_pt_regs) +#else +#define bpf_kprobe_multi_pt_regs_ptr() (NULL) +#endif + static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt) { unsigned long __user usymbol; @@ -2819,7 +2826,7 @@ static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx) static int kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, - unsigned long entry_ip, struct pt_regs *regs, + unsigned long entry_ip, struct ftrace_regs *fregs, bool is_return, void *data) { struct bpf_kprobe_multi_run_ctx run_ctx = { @@ -2831,6 +2838,7 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, .entry_ip = entry_ip, }; struct bpf_run_ctx *old_run_ctx; + struct pt_regs *regs; int err; if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { @@ -2841,6 +2849,7 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, migrate_disable(); rcu_read_lock(); + regs = ftrace_partial_regs(fregs, bpf_kprobe_multi_pt_regs_ptr()); old_run_ctx = bpf_set_run_ctx(&run_ctx.session_ctx.run_ctx); err = bpf_prog_run(link->link.prog, regs); bpf_reset_run_ctx(old_run_ctx); @@ -2857,15 +2866,11 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, unsigned long ret_ip, struct ftrace_regs *fregs, void *data) { - struct pt_regs *regs = ftrace_get_regs(fregs); struct bpf_kprobe_multi_link *link; int err; - if (!regs) - return 0; - link = container_of(fp, struct bpf_kprobe_multi_link, fp); - err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, false, data); + err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), fregs, false, data); return is_kprobe_session(link->link.prog) ? err : 0; } @@ -2875,13 +2880,9 @@ kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip, void *data) { struct bpf_kprobe_multi_link *link; - struct pt_regs *regs = ftrace_get_regs(fregs); - - if (!regs) - return; link = container_of(fp, struct bpf_kprobe_multi_link, fp); - kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, true, data); + kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), fregs, true, data); } static int symbols_cmp_r(const void *a, const void *b, const void *priv) @@ -3142,7 +3143,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr kvfree(cookies); return err; } -#else /* !CONFIG_FPROBE || !CONFIG_DYNAMIC_FTRACE_WITH_REGS */ +#else /* !CONFIG_FPROBE */ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { return -EOPNOTSUPP; From patchwork Mon Jun 17 01:48:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699872 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7E3D0161310; Mon, 17 Jun 2024 01:48:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588933; cv=none; b=N2nma1qbnW+LUtZbxbbHEQQvwvkFj9p3bvhysmArlHwXoDs7Eyd51eckZkRonODzscwqKndITVPzx1IRVVWS794s+6wadw6t4YzhWvPizBg82nVNB//oUHWdLi3IAZ3lV4ZHXdmmTjIhnJdMwWpvoXZuR74kHr4xi+ofWxP/cQU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588933; c=relaxed/simple; bh=1IbI7RJHmpJJegihE9ll7LfxD0xRdkv6aiTgyLl3LiE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=OQ0sCaLcKQh6H9SNskdHLNrBfMOYwNejMTg0+GsD6DiAVMv2bgl+ck+toEKeULbrNOTir7Qc4KTCSSuFyNLvaIgynvotHv9n/yuVdgxO7oD2AlV3wTs/I3IwhnMTVnCfyEcCYVAQb7v+vcn1iRsRBqLhZxf+uPz7TUR0OEAhzPQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CWnb4GVV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CWnb4GVV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4EF0DC2BBFC; Mon, 17 Jun 2024 01:48:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588933; bh=1IbI7RJHmpJJegihE9ll7LfxD0xRdkv6aiTgyLl3LiE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CWnb4GVV3KR4QQ/yWzhup2tbxLiEr/E0B8mhOSRISMq+YXQT3FCMk+civ9W6fi38D omN2JH/Zonz2RRGQwnslBU6Lcqk08qdtQT8yP2FU2LLq15f0XR8gA9w2RbULbEA5p9 0mWvE2t+mIpyKQjgUCyrkllU+aWPFaR6+9rEHZZxwPwQPM+PZXp+BbYNyQinEEOYkc 6oaMo5LXwbOud7mqjFa17XfaOVoym7x1HLWLP1W+9auklJ93YcosBqWmtkfZQ1ynAX L8Vq0Yn1nDO6sYiVhzfT84QD5tF8QCv0AHGwTgTsSjNEjcc+H3huJlCbFWD7tIt3qR ykjChle+tsCeg== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 12/18] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC Date: Mon, 17 Jun 2024 10:48:47 +0900 Message-Id: <171858892707.288820.16389691613899933338.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Add CONFIG_HAVE_FTRACE_GRAPH_FUNC kconfig in addition to ftrace_graph_func macro check. This is for the other feature (e.g. FPROBE) which requires to access ftrace_regs from fgraph_ops::entryfunc() can avoid compiling if the fgraph can not pass the valid ftrace_regs. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v8: - Newly added. --- arch/arm64/Kconfig | 1 + arch/loongarch/Kconfig | 1 + arch/powerpc/Kconfig | 1 + arch/riscv/Kconfig | 1 + arch/x86/Kconfig | 1 + kernel/trace/Kconfig | 5 +++++ 6 files changed, 10 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 8691683d782e..e99a3fd53efd 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -207,6 +207,7 @@ config ARM64 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI select HAVE_EFFICIENT_UNALIGNED_ACCESS select HAVE_GUP_FAST + select HAVE_FTRACE_GRAPH_FUNC select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_TRACER select HAVE_FUNCTION_ERROR_INJECTION diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 0f1b2057507b..f1439c42c46a 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -126,6 +126,7 @@ config LOONGARCH select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN select HAVE_EXIT_THREAD select HAVE_GUP_FAST + select HAVE_FTRACE_GRAPH_FUNC select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_ARG_ACCESS_API select HAVE_FUNCTION_ERROR_INJECTION diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index c88c6d46a5bc..910118faedaa 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -239,6 +239,7 @@ config PPC select HAVE_EBPF_JIT select HAVE_EFFICIENT_UNALIGNED_ACCESS select HAVE_GUP_FAST + select HAVE_FTRACE_GRAPH_FUNC select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_ARG_ACCESS_API select HAVE_FUNCTION_DESCRIPTORS if PPC64_ELF_ABI_V1 diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 1904393bc399..83e8c8c64b99 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -130,6 +130,7 @@ config RISCV select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE + select HAVE_FTRACE_GRAPH_FUNC select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_GRAPH_FREGS diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d4655b72e6d7..7213e27b5b2b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -228,6 +228,7 @@ config X86 select HAVE_EXIT_THREAD select HAVE_GUP_FAST select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE + select HAVE_FTRACE_GRAPH_FUNC if HAVE_FUNCTION_GRAPH_TRACER select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_GRAPH_FREGS if HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_GRAPH_TRACER if X86_32 || (X86_64 && DYNAMIC_FTRACE) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 4a3dd81f749b..a1fa9cba0ef3 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -34,6 +34,11 @@ config HAVE_FUNCTION_GRAPH_TRACER config HAVE_FUNCTION_GRAPH_FREGS bool +config HAVE_FTRACE_GRAPH_FUNC + bool + help + True if ftrace_graph_func() is defined. + config HAVE_DYNAMIC_FTRACE bool help From patchwork Mon Jun 17 01:48:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699873 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 698F5161310; Mon, 17 Jun 2024 01:49:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588945; cv=none; b=ACcjZEg7xNYUnYfk+7twab4Kobqva/iR29wOcbO49XsDYaO7PdABUVYF+nQtDuPY3TzJ7ThOblHlpF/N6QqDsWQDb2I/ufoSmJW/yVsxYgTt3Lc7UIpMAGAU2oATdS45pIqKdXs5koWLuAuGdUj4m5wwfDxSNJZQ99QtlLq1PzQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588945; c=relaxed/simple; bh=AjwqvRwtuXD6AZUNbhtCsn5uTlpdjpV3r32fyO2Kg1I=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=oZfoIOSV0PPdmLSFR57w6fGqrHN28+gRtELcauTAPEdRJnK86f64/CImGs47RidXzOkjRVCKvF7ozMzqXxw2QDiLKIu0uieg3dYqrBF1UGpLd1YbFXkk8VZoScZHvOllobBBhvD0TrcRreuj5u0HZGfVrVktfI17K3DEGv9cmCs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bqfh6P04; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bqfh6P04" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C13A1C2BBFC; Mon, 17 Jun 2024 01:49:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588944; bh=AjwqvRwtuXD6AZUNbhtCsn5uTlpdjpV3r32fyO2Kg1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bqfh6P042oOwObkE7sY0tWm4MbIn+0vGAqQuYznldOUNIqT5dkcCT+u5KnLWUBEu4 eDPi1OucYcht4THMxSOlNpHjMaVV3V1/5hYjdseUnpB27xKWacRJvpamGQ41CvpUqm X1LYX+o7CTXuAmYXaD+PlQ+fLGq8EMTvbQzh0hkd+0GvgMJYAaFTS6/Tl9z6fVJH0K Nio4Yd6SIfdF4KtFTGv3hFpOJXW0ggvUqR9bhWvuc9tawcWZ+9Juqfa+CANkkCUSxn met/ofTFAEWcUNWWAZbGk2HX+3dVdZM/NT74/qt29TFeLXAL7LlmY7vcc+W/kWb/ps PO1VKl+1LUmxQ== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 13/18] fprobe: Rewrite fprobe on function-graph tracer Date: Mon, 17 Jun 2024 10:48:58 +0900 Message-Id: <171858893844.288820.8155461947136622506.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Rewrite fprobe implementation on function-graph tracer. Major API changes are: - 'nr_maxactive' field is deprecated. - This depends on CONFIG_DYNAMIC_FTRACE_WITH_ARGS or !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS, and CONFIG_HAVE_FUNCTION_GRAPH_FREGS. So currently works only on x86_64. - Currently the entry size is limited in 15 * sizeof(long). - If there is too many fprobe exit handler set on the same function, it will fail to probe. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v9: - Remove unneeded prototype of ftrace_regs_get_return_address(). - Fix entry data address calculation. - Remove DIV_ROUND_UP() from hotpath. Changes in v8: - Use trace_func_graph_ret/ent_t for fgraph_ops. - Update CONFIG_FPROBE dependencies. - Add ftrace_regs_get_return_address() for each arch. Changes in v3: - Update for new reserve_data/retrieve_data API. - Fix internal push/pop on fgraph data logic so that it can correctly save/restore the returning fprobes. Changes in v2: - Add more lockdep_assert_held(fprobe_mutex) - Use READ_ONCE() and WRITE_ONCE() for fprobe_hlist_node::fp. - Add NOKPROBE_SYMBOL() for the functions which is called from entry/exit callback. --- arch/arm64/include/asm/ftrace.h | 6 arch/loongarch/include/asm/ftrace.h | 6 arch/powerpc/include/asm/ftrace.h | 6 arch/s390/include/asm/ftrace.h | 6 arch/x86/include/asm/ftrace.h | 6 include/linux/fprobe.h | 53 ++- kernel/trace/Kconfig | 8 kernel/trace/fprobe.c | 638 +++++++++++++++++++++++++---------- lib/test_fprobe.c | 45 -- 9 files changed, 529 insertions(+), 245 deletions(-) diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index 14ecb9a418d9..27e32f323048 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -132,6 +132,12 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) return fregs->fp; } +static __always_inline unsigned long +ftrace_regs_get_return_address(const struct ftrace_regs *fregs) +{ + return fregs->lr; +} + static __always_inline struct pt_regs * ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) { diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index 1a73f35ea9af..c021aa3194f3 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -80,6 +80,12 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) #define ftrace_regs_get_frame_pointer(fregs) \ ((fregs)->regs.regs[22]) +static __always_inline unsigned long +ftrace_regs_get_return_address(struct ftrace_regs *fregs) +{ + return *(unsigned long *)(fregs->regs.regs[1]); +} + #define ftrace_graph_func ftrace_graph_func void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index e6ff6834bf7e..2a2d070dd23c 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -75,6 +75,12 @@ ftrace_regs_get_instruction_pointer(struct ftrace_regs *fregs) #define ftrace_regs_query_register_offset(name) \ regs_query_register_offset(name) +static __always_inline unsigned long +ftrace_regs_get_return_address(struct ftrace_regs *fregs) +{ + return fregs->regs.link; +} + struct ftrace_ops; #define ftrace_graph_func ftrace_graph_func diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 0d9f6df21f81..7b80ff4d3386 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -84,6 +84,12 @@ ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs) return sp[0]; /* return backchain */ } +static __always_inline unsigned long +ftrace_regs_get_return_address(const struct ftrace_regs *fregs) +{ + return fregs->regs.gprs[14]; +} + #define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ (_regs)->psw.addr = (fregs)->regs.psw.addr; \ (_regs)->gprs[15] = (fregs)->regs.gprs[15]; \ diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 1f4d1f7b19ed..8472ba394091 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -74,6 +74,12 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) #define ftrace_regs_get_frame_pointer(fregs) \ frame_pointer(&(fregs)->regs) +static __always_inline unsigned long +ftrace_regs_get_return_address(struct ftrace_regs *fregs) +{ + return *(unsigned long *)ftrace_regs_get_stack_pointer(fregs); +} + struct ftrace_ops; #define ftrace_graph_func ftrace_graph_func void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index ef609bcca0f9..2d06bbd99601 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -5,10 +5,11 @@ #include #include -#include +#include +#include +#include struct fprobe; - typedef int (*fprobe_entry_cb)(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct ftrace_regs *regs, void *entry_data); @@ -17,35 +18,57 @@ typedef void (*fprobe_exit_cb)(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct ftrace_regs *regs, void *entry_data); +/** + * strcut fprobe_hlist_node - address based hash list node for fprobe. + * + * @hlist: The hlist node for address search hash table. + * @addr: The address represented by this. + * @fp: The fprobe which owns this. + */ +struct fprobe_hlist_node { + struct hlist_node hlist; + unsigned long addr; + struct fprobe *fp; +}; + +/** + * struct fprobe_hlist - hash list nodes for fprobe. + * + * @hlist: The hlist node for existence checking hash table. + * @rcu: rcu_head for RCU deferred release. + * @fp: The fprobe which owns this fprobe_hlist. + * @size: The size of @array. + * @array: The fprobe_hlist_node for each address to probe. + */ +struct fprobe_hlist { + struct hlist_node hlist; + struct rcu_head rcu; + struct fprobe *fp; + int size; + struct fprobe_hlist_node array[]; +}; + /** * struct fprobe - ftrace based probe. - * @ops: The ftrace_ops. + * * @nmissed: The counter for missing events. * @flags: The status flag. - * @rethook: The rethook data structure. (internal data) * @entry_data_size: The private data storage size. - * @nr_maxactive: The max number of active functions. + * @nr_maxactive: The max number of active functions. (*deprecated) * @entry_handler: The callback function for function entry. * @exit_handler: The callback function for function exit. + * @hlist_array: The fprobe_hlist for fprobe search from IP hash table. */ struct fprobe { -#ifdef CONFIG_FUNCTION_TRACER - /* - * If CONFIG_FUNCTION_TRACER is not set, CONFIG_FPROBE is disabled too. - * But user of fprobe may keep embedding the struct fprobe on their own - * code. To avoid build error, this will keep the fprobe data structure - * defined here, but remove ftrace_ops data structure. - */ - struct ftrace_ops ops; -#endif unsigned long nmissed; unsigned int flags; - struct rethook *rethook; size_t entry_data_size; int nr_maxactive; fprobe_entry_cb entry_handler; fprobe_exit_cb exit_handler; + + struct fprobe_hlist *hlist_array; }; /* This fprobe is soft-disabled. */ diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index a1fa9cba0ef3..d7d7b2624fed 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -298,11 +298,9 @@ config DYNAMIC_FTRACE_WITH_ARGS config FPROBE bool "Kernel Function Probe (fprobe)" - depends on FUNCTION_TRACER - depends on DYNAMIC_FTRACE_WITH_REGS || DYNAMIC_FTRACE_WITH_ARGS - depends on HAVE_PT_REGS_TO_FTRACE_REGS_CAST || !HAVE_DYNAMIC_FTRACE_WITH_ARGS - depends on HAVE_RETHOOK - select RETHOOK + depends on FUNCTION_GRAPH_TRACER + depends on HAVE_FUNCTION_GRAPH_FREGS && HAVE_FTRACE_GRAPH_FUNC + depends on DYNAMIC_FTRACE_WITH_ARGS default n help This option enables kernel function probe (fprobe) based on ftrace. diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 90a3c8e2bbdf..afa52d9816cf 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -8,98 +8,195 @@ #include #include #include -#include +#include +#include #include #include #include "trace.h" -struct fprobe_rethook_node { - struct rethook_node node; - unsigned long entry_ip; - unsigned long entry_parent_ip; - char data[]; -}; +#define FPROBE_IP_HASH_BITS 8 +#define FPROBE_IP_TABLE_SIZE (1 << FPROBE_IP_HASH_BITS) -static inline void __fprobe_handler(unsigned long ip, unsigned long parent_ip, - struct ftrace_ops *ops, struct ftrace_regs *fregs) -{ - struct fprobe_rethook_node *fpr; - struct rethook_node *rh = NULL; - struct fprobe *fp; - void *entry_data = NULL; - int ret = 0; +#define FPROBE_HASH_BITS 6 +#define FPROBE_TABLE_SIZE (1 << FPROBE_HASH_BITS) - fp = container_of(ops, struct fprobe, ops); +#define SIZE_IN_LONG(x) ((x + sizeof(long) - 1) >> (sizeof(long) == 8 ? 3 : 2)) - if (fp->exit_handler) { - rh = rethook_try_get(fp->rethook); - if (!rh) { - fp->nmissed++; - return; - } - fpr = container_of(rh, struct fprobe_rethook_node, node); - fpr->entry_ip = ip; - fpr->entry_parent_ip = parent_ip; - if (fp->entry_data_size) - entry_data = fpr->data; +/* + * fprobe_table: hold 'fprobe_hlist::hlist' for checking the fprobe still + * exists. The key is the address of fprobe instance. + * fprobe_ip_table: hold 'fprobe_hlist::array[*]' for searching the fprobe + * instance related to the funciton address. The key is the ftrace IP + * address. + * + * When unregistering the fprobe, fprobe_hlist::fp and fprobe_hlist::array[*].fp + * are set NULL and delete those from both hash tables (by hlist_del_rcu). + * After an RCU grace period, the fprobe_hlist itself will be released. + * + * fprobe_table and fprobe_ip_table can be accessed from either + * - Normal hlist traversal and RCU add/del under 'fprobe_mutex' is held. + * - RCU hlist traversal under disabling preempt + */ +static struct hlist_head fprobe_table[FPROBE_TABLE_SIZE]; +static struct hlist_head fprobe_ip_table[FPROBE_IP_TABLE_SIZE]; +static DEFINE_MUTEX(fprobe_mutex); + +/* + * Find first fprobe in the hlist. It will be iterated twice in the entry + * probe, once for correcting the total required size, the second time is + * calling back the user handlers. + * Thus the hlist in the fprobe_table must be sorted and new probe needs to + * be added *before* the first fprobe. + */ +static struct fprobe_hlist_node *find_first_fprobe_node(unsigned long ip) +{ + struct fprobe_hlist_node *node; + struct hlist_head *head; + + head = &fprobe_ip_table[hash_ptr((void *)ip, FPROBE_IP_HASH_BITS)]; + hlist_for_each_entry_rcu(node, head, hlist, + lockdep_is_held(&fprobe_mutex)) { + if (node->addr == ip) + return node; } + return NULL; +} +NOKPROBE_SYMBOL(find_first_fprobe_node); + +/* Node insertion and deletion requires the fprobe_mutex */ +static void insert_fprobe_node(struct fprobe_hlist_node *node) +{ + unsigned long ip = node->addr; + struct fprobe_hlist_node *next; + struct hlist_head *head; - if (fp->entry_handler) - ret = fp->entry_handler(fp, ip, parent_ip, fregs, entry_data); + lockdep_assert_held(&fprobe_mutex); - /* If entry_handler returns !0, nmissed is not counted. */ - if (rh) { - if (ret) - rethook_recycle(rh); - else - rethook_hook(rh, ftrace_get_regs(fregs), true); + next = find_first_fprobe_node(ip); + if (next) { + hlist_add_before_rcu(&node->hlist, &next->hlist); + return; } + head = &fprobe_ip_table[hash_ptr((void *)ip, FPROBE_IP_HASH_BITS)]; + hlist_add_head_rcu(&node->hlist, head); } -static void fprobe_handler(unsigned long ip, unsigned long parent_ip, - struct ftrace_ops *ops, struct ftrace_regs *fregs) +/* Return true if there are synonims */ +static bool delete_fprobe_node(struct fprobe_hlist_node *node) { - struct fprobe *fp; - int bit; + lockdep_assert_held(&fprobe_mutex); - fp = container_of(ops, struct fprobe, ops); - if (fprobe_disabled(fp)) - return; + WRITE_ONCE(node->fp, NULL); + hlist_del_rcu(&node->hlist); + return !!find_first_fprobe_node(node->addr); +} - /* recursion detection has to go before any traceable function and - * all functions before this point should be marked as notrace - */ - bit = ftrace_test_recursion_trylock(ip, parent_ip); - if (bit < 0) { - fp->nmissed++; - return; +/* Check existence of the fprobe */ +static bool is_fprobe_still_exist(struct fprobe *fp) +{ + struct hlist_head *head; + struct fprobe_hlist *fph; + + head = &fprobe_table[hash_ptr(fp, FPROBE_HASH_BITS)]; + hlist_for_each_entry_rcu(fph, head, hlist, + lockdep_is_held(&fprobe_mutex)) { + if (fph->fp == fp) + return true; } - __fprobe_handler(ip, parent_ip, ops, fregs); - ftrace_test_recursion_unlock(bit); + return false; +} +NOKPROBE_SYMBOL(is_fprobe_still_exist); + +static int add_fprobe_hash(struct fprobe *fp) +{ + struct fprobe_hlist *fph = fp->hlist_array; + struct hlist_head *head; + + lockdep_assert_held(&fprobe_mutex); + if (WARN_ON_ONCE(!fph)) + return -EINVAL; + + if (is_fprobe_still_exist(fp)) + return -EEXIST; + + head = &fprobe_table[hash_ptr(fp, FPROBE_HASH_BITS)]; + hlist_add_head_rcu(&fp->hlist_array->hlist, head); + return 0; } -NOKPROBE_SYMBOL(fprobe_handler); -static void fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip, - struct ftrace_ops *ops, struct ftrace_regs *fregs) +static int del_fprobe_hash(struct fprobe *fp) { - struct fprobe *fp; - int bit; + struct fprobe_hlist *fph = fp->hlist_array; - fp = container_of(ops, struct fprobe, ops); - if (fprobe_disabled(fp)) - return; + lockdep_assert_held(&fprobe_mutex); - /* recursion detection has to go before any traceable function and - * all functions called before this point should be marked as notrace - */ - bit = ftrace_test_recursion_trylock(ip, parent_ip); - if (bit < 0) { - fp->nmissed++; - return; + if (WARN_ON_ONCE(!fph)) + return -EINVAL; + + if (!is_fprobe_still_exist(fp)) + return -ENOENT; + + fph->fp = NULL; + hlist_del_rcu(&fph->hlist); + return 0; +} + +/* The entry data size is 4 bits (=16) * sizeof(long) in maximum */ +#define FPROBE_HEADER_SIZE_BITS 4 +#define MAX_FPROBE_DATA_SIZE_WORD ((1L << FPROBE_HEADER_SIZE_BITS) - 1) +#define MAX_FPROBE_DATA_SIZE (MAX_FPROBE_DATA_SIZE_WORD * sizeof(long)) +#define FPROBE_HEADER_PTR_BITS (BITS_PER_LONG - FPROBE_HEADER_SIZE_BITS) +#define FPROBE_HEADER_PTR_MASK GENMASK(FPROBE_HEADER_PTR_BITS - 1, 0) +#define FPROBE_HEADER_SIZE sizeof(unsigned long) + +static inline unsigned long encode_fprobe_header(struct fprobe *fp, int size_words) +{ + if (WARN_ON_ONCE(size_words > MAX_FPROBE_DATA_SIZE_WORD || + ((unsigned long)fp & ~FPROBE_HEADER_PTR_MASK) != + ~FPROBE_HEADER_PTR_MASK)) { + return 0; } + return ((unsigned long)size_words << FPROBE_HEADER_PTR_BITS) | + ((unsigned long)fp & FPROBE_HEADER_PTR_MASK); +} + +/* Return reserved data size in words */ +static inline int decode_fprobe_header(unsigned long val, struct fprobe **fp) +{ + unsigned long ptr; + + ptr = (val & FPROBE_HEADER_PTR_MASK) | ~FPROBE_HEADER_PTR_MASK; + if (fp) + *fp = (struct fprobe *)ptr; + return val >> FPROBE_HEADER_PTR_BITS; +} + +/* + * fprobe shadow stack management: + * Since fprobe shares a single fgraph_ops, it needs to share the stack entry + * among the probes on the same function exit. Note that a new probe can be + * registered before a target function is returning, we can not use the hash + * table to find the corresponding probes. Thus the probe address is stored on + * the shadow stack with its entry data size. + * + */ +static inline int __fprobe_handler(unsigned long ip, unsigned long parent_ip, + struct fprobe *fp, struct ftrace_regs *fregs, + void *data) +{ + if (!fp->entry_handler) + return 0; + + return fp->entry_handler(fp, ip, parent_ip, fregs, data); +} +static inline int __fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip, + struct fprobe *fp, struct ftrace_regs *fregs, + void *data) +{ + int ret; /* * This user handler is shared with other kprobes and is not expected to be * called recursively. So if any other kprobe handler is running, this will @@ -108,45 +205,185 @@ static void fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip, */ if (unlikely(kprobe_running())) { fp->nmissed++; - goto recursion_unlock; + return 0; } kprobe_busy_begin(); - __fprobe_handler(ip, parent_ip, ops, fregs); + ret = __fprobe_handler(ip, parent_ip, fp, fregs, data); kprobe_busy_end(); - -recursion_unlock: - ftrace_test_recursion_unlock(bit); + return ret; } -static void fprobe_exit_handler(struct rethook_node *rh, void *data, - unsigned long ret_ip, struct pt_regs *regs) +static int fprobe_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops, + struct ftrace_regs *fregs) { - struct fprobe *fp = (struct fprobe *)data; - struct fprobe_rethook_node *fpr; - struct ftrace_regs *fregs = (struct ftrace_regs *)regs; - int bit; + struct fprobe_hlist_node *node, *first; + unsigned long *fgraph_data = NULL; + unsigned long func = trace->func; + unsigned long header, ret_ip; + int reserved_words; + struct fprobe *fp; + int used, ret; - if (!fp || fprobe_disabled(fp)) - return; + if (WARN_ON_ONCE(!fregs)) + return 0; + + first = node = find_first_fprobe_node(func); + if (unlikely(!first)) + return 0; - fpr = container_of(rh, struct fprobe_rethook_node, node); + reserved_words = 0; + hlist_for_each_entry_from_rcu(node, hlist) { + if (node->addr != func) + break; + fp = READ_ONCE(node->fp); + if (!fp || !fp->exit_handler) + continue; + /* + * Since fprobe can be enabled until the next loop, we ignore the + * fprobe's disabled flag in this loop. + */ + reserved_words += + SIZE_IN_LONG(fp->entry_data_size) + 1; + } + node = first; + if (reserved_words) { + fgraph_data = fgraph_reserve_data(gops->idx, reserved_words * sizeof(long)); + if (unlikely(!fgraph_data)) { + hlist_for_each_entry_from_rcu(node, hlist) { + if (node->addr != func) + break; + fp = READ_ONCE(node->fp); + if (fp && !fprobe_disabled(fp)) + fp->nmissed++; + } + return 0; + } + } /* - * we need to assure no calls to traceable functions in-between the - * end of fprobe_handler and the beginning of fprobe_exit_handler. + * TODO: recursion detection has been done in the fgraph. Thus we need + * to add a callback to increment missed counter. */ - bit = ftrace_test_recursion_trylock(fpr->entry_ip, fpr->entry_parent_ip); - if (bit < 0) { - fp->nmissed++; + ret_ip = ftrace_regs_get_return_address(fregs); + used = 0; + hlist_for_each_entry_from_rcu(node, hlist) { + void *data; + + if (node->addr != func) + break; + fp = READ_ONCE(node->fp); + if (!fp || fprobe_disabled(fp)) + continue; + + if (fp->entry_data_size && fp->exit_handler) + data = fgraph_data + used + 1; + else + data = NULL; + + if (fprobe_shared_with_kprobes(fp)) + ret = __fprobe_kprobe_handler(func, ret_ip, fp, fregs, data); + else + ret = __fprobe_handler(func, ret_ip, fp, fregs, data); + /* If entry_handler returns !0, nmissed is not counted but skips exit_handler. */ + if (!ret && fp->exit_handler) { + int size_words = SIZE_IN_LONG(fp->entry_data_size); + + header = encode_fprobe_header(fp, size_words); + if (likely(header)) { + fgraph_data[used] = header; + used += size_words + 1; + } + } + } + if (used < reserved_words) + memset(fgraph_data + used, 0, reserved_words - used); + + /* If any exit_handler is set, data must be used. */ + return used != 0; +} +NOKPROBE_SYMBOL(fprobe_entry); + +static void fprobe_return(struct ftrace_graph_ret *trace, + struct fgraph_ops *gops, + struct ftrace_regs *fregs) +{ + unsigned long *fgraph_data = NULL; + unsigned long ret_ip; + unsigned long val; + struct fprobe *fp; + int size, curr; + int size_words; + + fgraph_data = (unsigned long *)fgraph_retrieve_data(gops->idx, &size); + if (WARN_ON_ONCE(!fgraph_data)) return; + size_words = SIZE_IN_LONG(size); + ret_ip = ftrace_regs_get_instruction_pointer(fregs); + + preempt_disable(); + + curr = 0; + while (size_words > curr) { + val = fgraph_data[curr++]; + if (!val) + break; + + size = decode_fprobe_header(val, &fp); + if (fp && is_fprobe_still_exist(fp) && !fprobe_disabled(fp)) { + if (WARN_ON_ONCE(curr + size > size_words)) + break; + fp->exit_handler(fp, trace->func, ret_ip, fregs, + size ? fgraph_data + curr : NULL); + } + curr += size; } + preempt_enable(); +} +NOKPROBE_SYMBOL(fprobe_return); + +static struct fgraph_ops fprobe_graph_ops = { + .entryfunc = fprobe_entry, + .retfunc = fprobe_return, +}; +static int fprobe_graph_active; - fp->exit_handler(fp, fpr->entry_ip, ret_ip, fregs, - fp->entry_data_size ? (void *)fpr->data : NULL); - ftrace_test_recursion_unlock(bit); +/* Add @addrs to the ftrace filter and register fgraph if needed. */ +static int fprobe_graph_add_ips(unsigned long *addrs, int num) +{ + int ret; + + lockdep_assert_held(&fprobe_mutex); + + ret = ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 0, 0); + if (ret) + return ret; + + if (!fprobe_graph_active) { + ret = register_ftrace_graph(&fprobe_graph_ops); + if (WARN_ON_ONCE(ret)) { + ftrace_free_filter(&fprobe_graph_ops.ops); + return ret; + } + } + fprobe_graph_active++; + return 0; +} + +/* Remove @addrs from the ftrace filter and unregister fgraph if possible. */ +static void fprobe_graph_remove_ips(unsigned long *addrs, int num) +{ + lockdep_assert_held(&fprobe_mutex); + + fprobe_graph_active--; + if (!fprobe_graph_active) { + /* Q: should we unregister it ? */ + unregister_ftrace_graph(&fprobe_graph_ops); + return; + } + + ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0); } -NOKPROBE_SYMBOL(fprobe_exit_handler); static int symbols_cmp(const void *a, const void *b) { @@ -176,54 +413,97 @@ static unsigned long *get_ftrace_locations(const char **syms, int num) return ERR_PTR(-ENOENT); } -static void fprobe_init(struct fprobe *fp) -{ - fp->nmissed = 0; - if (fprobe_shared_with_kprobes(fp)) - fp->ops.func = fprobe_kprobe_handler; - else - fp->ops.func = fprobe_handler; - - fp->ops.flags |= FTRACE_OPS_FL_SAVE_REGS; -} +struct filter_match_data { + const char *filter; + const char *notfilter; + size_t index; + size_t size; + unsigned long *addrs; +}; -static int fprobe_init_rethook(struct fprobe *fp, int num) +static int filter_match_callback(void *data, const char *name, unsigned long addr) { - int size; + struct filter_match_data *match = data; - if (!fp->exit_handler) { - fp->rethook = NULL; + if (!glob_match(match->filter, name) || + (match->notfilter && glob_match(match->notfilter, name))) return 0; - } - /* Initialize rethook if needed */ - if (fp->nr_maxactive) - num = fp->nr_maxactive; - else - num *= num_possible_cpus() * 2; - if (num <= 0) - return -EINVAL; + if (!ftrace_location(addr)) + return 0; - size = sizeof(struct fprobe_rethook_node) + fp->entry_data_size; + if (match->addrs) + match->addrs[match->index] = addr; - /* Initialize rethook */ - fp->rethook = rethook_alloc((void *)fp, fprobe_exit_handler, size, num); - if (IS_ERR(fp->rethook)) - return PTR_ERR(fp->rethook); + match->index++; + return match->index == match->size; +} - return 0; +/* + * Make IP list from the filter/no-filter glob patterns. + * Return the number of matched symbols, or -ENOENT. + */ +static int ip_list_from_filter(const char *filter, const char *notfilter, + unsigned long *addrs, size_t size) +{ + struct filter_match_data match = { .filter = filter, .notfilter = notfilter, + .index = 0, .size = size, .addrs = addrs}; + int ret; + + ret = kallsyms_on_each_symbol(filter_match_callback, &match); + if (ret < 0) + return ret; + ret = module_kallsyms_on_each_symbol(NULL, filter_match_callback, &match); + if (ret < 0) + return ret; + + return match.index ?: -ENOENT; } static void fprobe_fail_cleanup(struct fprobe *fp) { - if (!IS_ERR_OR_NULL(fp->rethook)) { - /* Don't need to cleanup rethook->handler because this is not used. */ - rethook_free(fp->rethook); - fp->rethook = NULL; + kfree(fp->hlist_array); + fp->hlist_array = NULL; +} + +/* Initialize the fprobe data structure. */ +static int fprobe_init(struct fprobe *fp, unsigned long *addrs, int num) +{ + struct fprobe_hlist *hlist_array; + unsigned long addr; + int size, i; + + if (!fp || !addrs || num <= 0) + return -EINVAL; + + size = ALIGN(fp->entry_data_size, sizeof(long)); + if (size > MAX_FPROBE_DATA_SIZE) + return -E2BIG; + fp->entry_data_size = size; + + hlist_array = kzalloc(struct_size(hlist_array, array, num), GFP_KERNEL); + if (!hlist_array) + return -ENOMEM; + + fp->nmissed = 0; + + hlist_array->size = num; + fp->hlist_array = hlist_array; + hlist_array->fp = fp; + for (i = 0; i < num; i++) { + hlist_array->array[i].fp = fp; + addr = ftrace_location(addrs[i]); + if (!addr) { + fprobe_fail_cleanup(fp); + return -ENOENT; + } + hlist_array->array[i].addr = addr; } - ftrace_free_filter(&fp->ops); + return 0; } +#define FPROBE_IPS_MAX INT_MAX + /** * register_fprobe() - Register fprobe to ftrace by pattern. * @fp: A fprobe data structure to be registered. @@ -237,46 +517,24 @@ static void fprobe_fail_cleanup(struct fprobe *fp) */ int register_fprobe(struct fprobe *fp, const char *filter, const char *notfilter) { - struct ftrace_hash *hash; - unsigned char *str; - int ret, len; + unsigned long *addrs; + int ret; if (!fp || !filter) return -EINVAL; - fprobe_init(fp); - - len = strlen(filter); - str = kstrdup(filter, GFP_KERNEL); - ret = ftrace_set_filter(&fp->ops, str, len, 0); - kfree(str); - if (ret) + ret = ip_list_from_filter(filter, notfilter, NULL, FPROBE_IPS_MAX); + if (ret < 0) return ret; - if (notfilter) { - len = strlen(notfilter); - str = kstrdup(notfilter, GFP_KERNEL); - ret = ftrace_set_notrace(&fp->ops, str, len, 0); - kfree(str); - if (ret) - goto out; - } - - /* TODO: - * correctly calculate the total number of filtered symbols - * from both filter and notfilter. - */ - hash = rcu_access_pointer(fp->ops.local_hash.filter_hash); - if (WARN_ON_ONCE(!hash)) - goto out; - - ret = fprobe_init_rethook(fp, (int)hash->count); - if (!ret) - ret = register_ftrace_function(&fp->ops); + addrs = kcalloc(ret, sizeof(unsigned long), GFP_KERNEL); + if (!addrs) + return -ENOMEM; + ret = ip_list_from_filter(filter, notfilter, addrs, ret); + if (ret > 0) + ret = register_fprobe_ips(fp, addrs, ret); -out: - if (ret) - fprobe_fail_cleanup(fp); + kfree(addrs); return ret; } EXPORT_SYMBOL_GPL(register_fprobe); @@ -284,7 +542,7 @@ EXPORT_SYMBOL_GPL(register_fprobe); /** * register_fprobe_ips() - Register fprobe to ftrace by address. * @fp: A fprobe data structure to be registered. - * @addrs: An array of target ftrace location addresses. + * @addrs: An array of target function address. * @num: The number of entries of @addrs. * * Register @fp to ftrace for enabling the probe on the address given by @addrs. @@ -296,23 +554,27 @@ EXPORT_SYMBOL_GPL(register_fprobe); */ int register_fprobe_ips(struct fprobe *fp, unsigned long *addrs, int num) { - int ret; - - if (!fp || !addrs || num <= 0) - return -EINVAL; - - fprobe_init(fp); + struct fprobe_hlist *hlist_array; + int ret, i; - ret = ftrace_set_filter_ips(&fp->ops, addrs, num, 0, 0); + ret = fprobe_init(fp, addrs, num); if (ret) return ret; - ret = fprobe_init_rethook(fp, num); - if (!ret) - ret = register_ftrace_function(&fp->ops); + mutex_lock(&fprobe_mutex); + + hlist_array = fp->hlist_array; + ret = fprobe_graph_add_ips(addrs, num); + if (!ret) { + add_fprobe_hash(fp); + for (i = 0; i < hlist_array->size; i++) + insert_fprobe_node(&hlist_array->array[i]); + } + mutex_unlock(&fprobe_mutex); if (ret) fprobe_fail_cleanup(fp); + return ret; } EXPORT_SYMBOL_GPL(register_fprobe_ips); @@ -350,14 +612,13 @@ EXPORT_SYMBOL_GPL(register_fprobe_syms); bool fprobe_is_registered(struct fprobe *fp) { - if (!fp || (fp->ops.saved_func != fprobe_handler && - fp->ops.saved_func != fprobe_kprobe_handler)) + if (!fp || !fp->hlist_array) return false; return true; } /** - * unregister_fprobe() - Unregister fprobe from ftrace + * unregister_fprobe() - Unregister fprobe. * @fp: A fprobe data structure to be unregistered. * * Unregister fprobe (and remove ftrace hooks from the function entries). @@ -366,23 +627,40 @@ bool fprobe_is_registered(struct fprobe *fp) */ int unregister_fprobe(struct fprobe *fp) { - int ret; + struct fprobe_hlist *hlist_array; + unsigned long *addrs = NULL; + int ret = 0, i, count; - if (!fprobe_is_registered(fp)) - return -EINVAL; + mutex_lock(&fprobe_mutex); + if (!fp || !is_fprobe_still_exist(fp)) { + ret = -EINVAL; + goto out; + } - if (!IS_ERR_OR_NULL(fp->rethook)) - rethook_stop(fp->rethook); + hlist_array = fp->hlist_array; + addrs = kcalloc(hlist_array->size, sizeof(unsigned long), GFP_KERNEL); + if (!addrs) { + ret = -ENOMEM; /* TODO: Fallback to one-by-one loop */ + goto out; + } - ret = unregister_ftrace_function(&fp->ops); - if (ret < 0) - return ret; + /* Remove non-synonim ips from table and hash */ + count = 0; + for (i = 0; i < hlist_array->size; i++) { + if (!delete_fprobe_node(&hlist_array->array[i])) + addrs[count++] = hlist_array->array[i].addr; + } + del_fprobe_hash(fp); - if (!IS_ERR_OR_NULL(fp->rethook)) - rethook_free(fp->rethook); + fprobe_graph_remove_ips(addrs, count); - ftrace_free_filter(&fp->ops); + kfree_rcu(hlist_array, rcu); + fp->hlist_array = NULL; +out: + mutex_unlock(&fprobe_mutex); + + kfree(addrs); return ret; } EXPORT_SYMBOL_GPL(unregister_fprobe); diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c index 271ce0caeec0..cf92111b5c79 100644 --- a/lib/test_fprobe.c +++ b/lib/test_fprobe.c @@ -17,10 +17,8 @@ static u32 rand1, entry_val, exit_val; /* Use indirect calls to avoid inlining the target functions */ static u32 (*target)(u32 value); static u32 (*target2)(u32 value); -static u32 (*target_nest)(u32 value, u32 (*nest)(u32)); static unsigned long target_ip; static unsigned long target2_ip; -static unsigned long target_nest_ip; static int entry_return_value; static noinline u32 fprobe_selftest_target(u32 value) @@ -33,11 +31,6 @@ static noinline u32 fprobe_selftest_target2(u32 value) return (value / div_factor) + 1; } -static noinline u32 fprobe_selftest_nest_target(u32 value, u32 (*nest)(u32)) -{ - return nest(value + 2); -} - static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, struct ftrace_regs *fregs, void *data) @@ -79,22 +72,6 @@ static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, KUNIT_EXPECT_NULL(current_test, data); } -static notrace int nest_entry_handler(struct fprobe *fp, unsigned long ip, - unsigned long ret_ip, - struct ftrace_regs *fregs, void *data) -{ - KUNIT_EXPECT_FALSE(current_test, preemptible()); - return 0; -} - -static notrace void nest_exit_handler(struct fprobe *fp, unsigned long ip, - unsigned long ret_ip, - struct ftrace_regs *fregs, void *data) -{ - KUNIT_EXPECT_FALSE(current_test, preemptible()); - KUNIT_EXPECT_EQ(current_test, ip, target_nest_ip); -} - /* Test entry only (no rethook) */ static void test_fprobe_entry(struct kunit *test) { @@ -191,25 +168,6 @@ static void test_fprobe_data(struct kunit *test) KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp)); } -/* Test nr_maxactive */ -static void test_fprobe_nest(struct kunit *test) -{ - static const char *syms[] = {"fprobe_selftest_target", "fprobe_selftest_nest_target"}; - struct fprobe fp = { - .entry_handler = nest_entry_handler, - .exit_handler = nest_exit_handler, - .nr_maxactive = 1, - }; - - current_test = test; - KUNIT_EXPECT_EQ(test, 0, register_fprobe_syms(&fp, syms, 2)); - - target_nest(rand1, target); - KUNIT_EXPECT_EQ(test, 1, fp.nmissed); - - KUNIT_EXPECT_EQ(test, 0, unregister_fprobe(&fp)); -} - static void test_fprobe_skip(struct kunit *test) { struct fprobe fp = { @@ -247,10 +205,8 @@ static int fprobe_test_init(struct kunit *test) rand1 = get_random_u32_above(div_factor); target = fprobe_selftest_target; target2 = fprobe_selftest_target2; - target_nest = fprobe_selftest_nest_target; target_ip = get_ftrace_location(target); target2_ip = get_ftrace_location(target2); - target_nest_ip = get_ftrace_location(target_nest); return 0; } @@ -260,7 +216,6 @@ static struct kunit_case fprobe_testcases[] = { KUNIT_CASE(test_fprobe), KUNIT_CASE(test_fprobe_syms), KUNIT_CASE(test_fprobe_data), - KUNIT_CASE(test_fprobe_nest), KUNIT_CASE(test_fprobe_skip), {} }; From patchwork Mon Jun 17 01:49:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699874 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CA11A160884; Mon, 17 Jun 2024 01:49:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588956; cv=none; b=tTUS33brxyN8rPO5X2BKgGXR0UQGZ7BXk55bwzFpIHmH/knJ13UoEFXA4LZSVAETbKH/zo18KHs8s1IvEB9IqXNvyT17GC5p6WBbRqfk5lroved1xMdJv3coTEM7sfUk3WSATqu1Dgzgoo14B42+nUkni5xk3kRjompZDNtdPkU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588956; c=relaxed/simple; bh=6LRuOvaZstDE6JovoZfd2CiVZaFBRwbUc1jP+rvwiso=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=G50W5dPfD4HXEftDCGq6w0VElL10j2aOAL/xLQUWoYAQJxU2Y0tndZHdAS0xwBWHLAOY5Jel9auDU5gd8czV8sxtN1GI+8t0BRGEXcBO8pfWL5Hi5UxuGblzCz+Goh6CdByY9fWAeV0w9E0FZHhdGlb9tr3IAZWPb1wB7dGsTn8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CoGVDpM5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CoGVDpM5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A7BDC2BBFC; Mon, 17 Jun 2024 01:49:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588956; bh=6LRuOvaZstDE6JovoZfd2CiVZaFBRwbUc1jP+rvwiso=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CoGVDpM5cqUI1Yonuijdd3lN1cTWNj2tbkhGyNWGBr4jnxKFPdjGepjqkfOa13Jx0 vIuxgvvcTTQDHPOZRrHeAbN9HAmK87b6VVDMWRovi9tamKs9eM61nX7qRsAPbjwTjH Hs3vAIdPxTL55IA7Ju4miREruJHlWZYaInootkcITaiJqjMRaeCjXukBG5oGziuHWr w/QPMvghXoHJtxHh+VM2FFbooRwb3XPorV9AV51jSSrMdTo46n17SJMsc4EzoKpA+b bXXi2CdaSYGvVOIjEnkqx54NL/rCFQG/jCkcpXPfcpui4eSB1aISugA1g6hAwurs4C 3MEPCwYHUn9GQ== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 14/18] tracing/fprobe: Remove nr_maxactive from fprobe Date: Mon, 17 Jun 2024 10:49:10 +0900 Message-Id: <171858895032.288820.2501510126596153887.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Remove depercated fprobe::nr_maxactive. This involves fprobe events to rejects the maxactive number. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v2: - Newly added. --- include/linux/fprobe.h | 2 -- kernel/trace/trace_fprobe.c | 44 ++++++------------------------------------- 2 files changed, 6 insertions(+), 40 deletions(-) diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index 2d06bbd99601..a86b3e4df2a0 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -54,7 +54,6 @@ struct fprobe_hlist { * @nmissed: The counter for missing events. * @flags: The status flag. * @entry_data_size: The private data storage size. - * @nr_maxactive: The max number of active functions. (*deprecated) * @entry_handler: The callback function for function entry. * @exit_handler: The callback function for function exit. * @hlist_array: The fprobe_hlist for fprobe search from IP hash table. @@ -63,7 +62,6 @@ struct fprobe { unsigned long nmissed; unsigned int flags; size_t entry_data_size; - int nr_maxactive; fprobe_entry_cb entry_handler; fprobe_exit_cb exit_handler; diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 86cd6a8c806a..20ef5cd5d419 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -422,7 +422,6 @@ static struct trace_fprobe *alloc_trace_fprobe(const char *group, const char *event, const char *symbol, struct tracepoint *tpoint, - int maxactive, int nargs, bool is_return) { struct trace_fprobe *tf; @@ -442,7 +441,6 @@ static struct trace_fprobe *alloc_trace_fprobe(const char *group, tf->fp.entry_handler = fentry_dispatcher; tf->tpoint = tpoint; - tf->fp.nr_maxactive = maxactive; ret = trace_probe_init(&tf->tp, event, group, false, nargs); if (ret < 0) @@ -1021,12 +1019,11 @@ static int __trace_fprobe_create(int argc, const char *argv[]) * FETCHARG:TYPE : use TYPE instead of unsigned long. */ struct trace_fprobe *tf = NULL; - int i, len, new_argc = 0, ret = 0; + int i, new_argc = 0, ret = 0; bool is_return = false; char *symbol = NULL; const char *event = NULL, *group = FPROBE_EVENT_SYSTEM; const char **new_argv = NULL; - int maxactive = 0; char buf[MAX_EVENT_NAME_LEN]; char gbuf[MAX_EVENT_NAME_LEN]; char sbuf[KSYM_NAME_LEN]; @@ -1048,33 +1045,13 @@ static int __trace_fprobe_create(int argc, const char *argv[]) trace_probe_log_init("trace_fprobe", argc, argv); - event = strchr(&argv[0][1], ':'); - if (event) - event++; - - if (isdigit(argv[0][1])) { - if (event) - len = event - &argv[0][1] - 1; - else - len = strlen(&argv[0][1]); - if (len > MAX_EVENT_NAME_LEN - 1) { - trace_probe_log_err(1, BAD_MAXACT); - goto parse_error; - } - memcpy(buf, &argv[0][1], len); - buf[len] = '\0'; - ret = kstrtouint(buf, 0, &maxactive); - if (ret || !maxactive) { + if (argv[0][1] != '\0') { + if (argv[0][1] != ':') { + trace_probe_log_set_index(0); trace_probe_log_err(1, BAD_MAXACT); goto parse_error; } - /* fprobe rethook instances are iterated over via a list. The - * maximum should stay reasonable. - */ - if (maxactive > RETHOOK_MAXACTIVE_MAX) { - trace_probe_log_err(1, MAXACT_TOO_BIG); - goto parse_error; - } + event = &argv[0][2]; } trace_probe_log_set_index(1); @@ -1084,12 +1061,6 @@ static int __trace_fprobe_create(int argc, const char *argv[]) if (ret < 0) goto parse_error; - if (!is_return && maxactive) { - trace_probe_log_set_index(0); - trace_probe_log_err(1, BAD_MAXACT_TYPE); - goto parse_error; - } - trace_probe_log_set_index(0); if (event) { ret = traceprobe_parse_event_name(&event, &group, gbuf, @@ -1147,8 +1118,7 @@ static int __trace_fprobe_create(int argc, const char *argv[]) goto out; /* setup a probe */ - tf = alloc_trace_fprobe(group, event, symbol, tpoint, maxactive, - argc, is_return); + tf = alloc_trace_fprobe(group, event, symbol, tpoint, argc, is_return); if (IS_ERR(tf)) { ret = PTR_ERR(tf); /* This must return -ENOMEM, else there is a bug */ @@ -1230,8 +1200,6 @@ static int trace_fprobe_show(struct seq_file *m, struct dyn_event *ev) seq_putc(m, 't'); else seq_putc(m, 'f'); - if (trace_fprobe_is_return(tf) && tf->fp.nr_maxactive) - seq_printf(m, "%d", tf->fp.nr_maxactive); seq_printf(m, ":%s/%s", trace_probe_group_name(&tf->tp), trace_probe_name(&tf->tp)); From patchwork Mon Jun 17 01:49:21 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699875 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F05F176ACB; Mon, 17 Jun 2024 01:49:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588969; cv=none; b=o/aKfOtowwQDK2RekJbtgO5Q+2y+d8IwqUOjXhdh2AgOuDMV20UIgtNLTBTGeVa08+eumHVwtBANGbRRq76SZdcH9kXu5hM0TS/kyf2UaF0ChQBp0/a+tCI/MGpc0kXfB14oHioBCn7hY0OPAPQpKNurXlpCgyRTLUPMzrYel98= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588969; c=relaxed/simple; bh=wZEjksI48uEO6V4KtS7yN1QVU17ztXbJ6mD6JSkXebk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=VJq0xhE/m3sPEm1+RLhy8nCrJHbyPGj98As/6o5xu3IKvQoRRdlAxay7k8N6rapfIXCidvipvSNW+sl5Y/rB6qHGrtH7aIE82pLD1rJQBFdEp13M7HaKene5vikKAlQj3lJTQACqXIE8Lk+cLPIiHZGbpzwzwzWjbDLv66KzMEM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jTQTMleJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jTQTMleJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 094A5C2BBFC; Mon, 17 Jun 2024 01:49:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588968; bh=wZEjksI48uEO6V4KtS7yN1QVU17ztXbJ6mD6JSkXebk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jTQTMleJgdHrF4CIZ6dfOjuVot/xgQybi1X2mSa60Bgw3hIDP9hL7Vi6qlWesRRqo Ei5ojmHZZbpMzErhqo0bqR+fb6PxwbZu9LIkrEkz9V1R/47sW+Nt3Wnuy76vR1EyVf AS2NJ80BsFIPlaJ2hTaazyHG3ZvEaUN7eN3myySlck9intvngNGPXsjxH0e6Zsxd/m X1u9M/UY7kG0u9Ubb/GPkdBkv1t3tNxSnPtYsrZi8anZqGC/vyF1O2VBZYtDkuqFRW I1UaCs3BjkG+g6uVX1OSl+EGt3z1uXo/JKuR+SdtSh/IBsVmtYxgkJiD0jzvdhcMRo CXb4/0G98b+Jw== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 15/18] selftests: ftrace: Remove obsolate maxactive syntax check Date: Mon, 17 Jun 2024 10:49:21 +0900 Message-Id: <171858896179.288820.12982870758086018964.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Since the fprobe event does not support maxactive anymore, stop testing the maxactive syntax error checking. Signed-off-by: Masami Hiramatsu (Google) --- .../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc index 61877d166451..c9425a34fae3 100644 --- a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc +++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc @@ -16,9 +16,7 @@ aarch64) REG=%r0 ;; esac -check_error 'f^100 vfs_read' # MAXACT_NO_KPROBE -check_error 'f^1a111 vfs_read' # BAD_MAXACT -check_error 'f^100000 vfs_read' # MAXACT_TOO_BIG +check_error 'f^100 vfs_read' # BAD_MAXACT check_error 'f ^non_exist_func' # BAD_PROBE_ADDR (enoent) check_error 'f ^vfs_read+10' # BAD_PROBE_ADDR From patchwork Mon Jun 17 01:49:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699876 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FD3D176ACB; Mon, 17 Jun 2024 01:49:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588980; cv=none; b=JYmXH7ZmqCm2mKoGYuDRQtZqxRqmBIHanCkkV4uDmjbyVxlZCXo4YeqmFaZvRcj4uy/TZvp01jth+nvC843gvYOFfDmPwYBJDojfLLJ6FUKDhUYR1WTvHQaVisdRHh726UE00iJwjbnBi8swO8NyE/0Mg5NWIzLd4kFaHHLb7wA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588980; c=relaxed/simple; bh=MTl3WOEWmkU7N1ZYT3IdZA3wW+cclx8nbkw1UKe91tQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=Q14ploVT4jeW9cuqXEgSkYMPMeJWHE0c4iwha41R0oixGe1m3iQraA92lZh6mgc6VS77tfzudhYkCORxIFNlZ9piETtBLN60Zd176fkYkXqFa4siiMzX4o/HOG+I0DVcdCTtCmMCmwR0WCXGZPbXYIFdUyRmGt3JTygw10gnvCM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hRMG5G0U; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hRMG5G0U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3631AC2BBFC; Mon, 17 Jun 2024 01:49:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588980; bh=MTl3WOEWmkU7N1ZYT3IdZA3wW+cclx8nbkw1UKe91tQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hRMG5G0Ucn99ph5OH3dis49xVzWILMbx96xvAWygPgRzsQLktijoJSb7uNREsyife uezWBadakSSn3hOK6tVcSrz4j3V4SeKKRPsU7bnim2msybyyCxoGF3eCq7eq94aI/w R5BQW8aLYG18LLjQsHYiKllf2zWp1zBB/mfIeH8UEMGXd2ETO+0qcxaKhfewGWdsxI HBfwBDRxELv4MdDTWFA7wGE3TUy6gfbyyRQX7ARkEuM80p8OhT1egCkZJWvzwdQlbL RMRikGmo15Pri431/4RWSYLCMiF/pUUYA3730nOVtWnZeDBSgvyQmr193F94b+7tFB BbTDgiE+0YjSA== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 16/18] selftests/ftrace: Add a test case for repeating register/unregister fprobe Date: Mon, 17 Jun 2024 10:49:34 +0900 Message-Id: <171858897398.288820.10111214744046943641.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) This test case repeats define and undefine the fprobe dynamic event to ensure that the fprobe does not cause any issue with such operations. Signed-off-by: Masami Hiramatsu (Google) --- .../test.d/dynevent/add_remove_fprobe_repeat.tc | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe_repeat.tc diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe_repeat.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe_repeat.tc new file mode 100644 index 000000000000..b4ad09237e2a --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe_repeat.tc @@ -0,0 +1,19 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Generic dynamic event - Repeating add/remove fprobe events +# requires: dynamic_events "f[:[/][]] [%return] []":README + +echo 0 > events/enable +echo > dynamic_events + +PLACE=$FUNCTION_FORK +REPEAT_TIMES=64 + +for i in `seq 1 $REPEAT_TIMES`; do + echo "f:myevent $PLACE" >> dynamic_events + grep -q myevent dynamic_events + test -d events/fprobes/myevent + echo > dynamic_events +done + +clear_trace From patchwork Mon Jun 17 01:49:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699877 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CB41317E476; Mon, 17 Jun 2024 01:49:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588991; cv=none; b=sp/pj2EmH5My/C1rdg/nfxxR8kEkbN7wYWJUpVH8B5mxKz46TIx6J5sLFn64NFrpk75RON1Lzt/As6UochiPL5rEfbrpG2op19QVrvbl538U9sUJ96IP2mZcix4F3ebjD+okzrF6KlNesRh40RH2l+m8EEnwBwYSxs83FZad2L4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718588991; c=relaxed/simple; bh=8t7YVZmoVUR7dCk/2nFP4SmQbrkuMwJVZH30PnGw0sc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=YpcsxNDjymhnRc99fG1vIgKZ20j1oOrDrN9sRnUPvosFeJLQ9L2WWxUFlumn4IF7UQO14kM/EuSC4l1gARDhri6c5sL8x64XiyBBNb71mNnKlJQ/NZWJ36kvknwEeVpHk7ny32bZksg4G23YxqxW5lirOqtMqbw2bqwRiApNPEU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iUq4K7Bl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iUq4K7Bl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A93AEC2BBFC; Mon, 17 Jun 2024 01:49:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718588991; bh=8t7YVZmoVUR7dCk/2nFP4SmQbrkuMwJVZH30PnGw0sc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iUq4K7Bl2GAB1Xr62kUKm/b90SSg+OYVS7za1NFD/b/m1jL3zazxZ5RVdBRDZeAz5 TN6GfiVsM0MEjBxWm5icBw3ZxRRESJn0YNI/8YMC+gPGXi7CXZSUTzfh/Wdzt0t+oE 04Q2CeP3/g5ciVeFsryR2i9MBZHBE1VUqh7VTgrqEJ1lwEdphWxdN+9RCdZRvZ2azR xRlkQ+0N7EanZhbaaubWzwerjKHz9u4FRNn3PC8BFvqeCZkUPzs3IxqYf0vxhTtha/ 7nuFUF4mcNEb4aaEbDIHoHIgmymz7NsQ42XmJZQxx7wmtay3U5CCXrRlnBqWccP3VE pR9/OZpNuwVWA== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 17/18] Documentation: probes: Update fprobe on function-graph tracer Date: Mon, 17 Jun 2024 10:49:45 +0900 Message-Id: <171858898545.288820.15711100814091028737.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Update fprobe documentation for the new fprobe on function-graph tracer. This includes some bahvior changes and pt_regs to ftrace_regs interface change. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v2: - Update @fregs parameter explanation. --- Documentation/trace/fprobe.rst | 42 ++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 15 deletions(-) diff --git a/Documentation/trace/fprobe.rst b/Documentation/trace/fprobe.rst index 196f52386aaa..f58bdc64504f 100644 --- a/Documentation/trace/fprobe.rst +++ b/Documentation/trace/fprobe.rst @@ -9,9 +9,10 @@ Fprobe - Function entry/exit probe Introduction ============ -Fprobe is a function entry/exit probe mechanism based on ftrace. -Instead of using ftrace full feature, if you only want to attach callbacks -on function entry and exit, similar to the kprobes and kretprobes, you can +Fprobe is a function entry/exit probe mechanism based on the function-graph +tracer. +Instead of tracing all functions, if you want to attach callbacks on specific +function entry and exit, similar to the kprobes and kretprobes, you can use fprobe. Compared with kprobes and kretprobes, fprobe gives faster instrumentation for multiple functions with single handler. This document describes how to use fprobe. @@ -91,12 +92,14 @@ The prototype of the entry/exit callback function are as follows: .. code-block:: c - int entry_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct pt_regs *regs, void *entry_data); + int entry_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data); - void exit_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct pt_regs *regs, void *entry_data); + void exit_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data); -Note that the @entry_ip is saved at function entry and passed to exit handler. -If the entry callback function returns !0, the corresponding exit callback will be cancelled. +Note that the @entry_ip is saved at function entry and passed to exit +handler. +If the entry callback function returns !0, the corresponding exit callback +will be cancelled. @fp This is the address of `fprobe` data structure related to this handler. @@ -112,12 +115,10 @@ If the entry callback function returns !0, the corresponding exit callback will This is the return address that the traced function will return to, somewhere in the caller. This can be used at both entry and exit. -@regs - This is the `pt_regs` data structure at the entry and exit. Note that - the instruction pointer of @regs may be different from the @entry_ip - in the entry_handler. If you need traced instruction pointer, you need - to use @entry_ip. On the other hand, in the exit_handler, the instruction - pointer of @regs is set to the current return address. +@fregs + This is the `ftrace_regs` data structure at the entry and exit. This + includes the function parameters, or the return values. So user can + access thos values via appropriate `ftrace_regs_*` APIs. @entry_data This is a local storage to share the data between entry and exit handlers. @@ -125,6 +126,17 @@ If the entry callback function returns !0, the corresponding exit callback will and `entry_data_size` field when registering the fprobe, the storage is allocated and passed to both `entry_handler` and `exit_handler`. +Entry data size and exit handlers on the same function +====================================================== + +Since the entry data is passed via per-task stack and it is has limited size, +the entry data size per probe is limited to `15 * sizeof(long)`. You also need +to take care that the different fprobes are probing on the same function, this +limit becomes smaller. The entry data size is aligned to `sizeof(long)` and +each fprobe which has exit handler uses a `sizeof(long)` space on the stack, +you should keep the number of fprobes on the same function as small as +possible. + Share the callbacks with kprobes ================================ @@ -165,8 +177,8 @@ This counter counts up when; - fprobe fails to take ftrace_recursion lock. This usually means that a function which is traced by other ftrace users is called from the entry_handler. - - fprobe fails to setup the function exit because of the shortage of rethook - (the shadow stack for hooking the function return.) + - fprobe fails to setup the function exit because of failing to allocate the + data buffer from the per-task shadow stack. The `fprobe::nmissed` field counts up in both cases. Therefore, the former skips both of entry and exit callback and the latter skips the exit From patchwork Mon Jun 17 01:49:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13699878 X-Patchwork-Delegate: bpf@iogearbox.net Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 28B8212FF6A; Mon, 17 Jun 2024 01:50:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718589003; cv=none; b=goj5RzJT+uNtZMLdDhcITQDJld6uI7M8wTUhRLKcEBphz2p0knQ4Ca5n2MDiJZA3EnS+dQau9S2iE3OEDHLs5a0BsghXn7lZWIMgGfFq20l3AET3sPUFC5BmP3fqutCfNRea23XSq3UqYTPBTkMXoTv0utNcusagc8JGimH8PeU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718589003; c=relaxed/simple; bh=NheZlQukXrHe+aAqSQt20W9ihRV2X4255gLoqcg7brw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=CpRSLUcuZ8bCIMQXpV9cZopsvm9ean1BFHDzfkRwg7yO2qSe550XnWYgvtyWb/o2NnVrOCA5x0PIuIMkk5WHDjJLIELhIU0MR8+tufcyuWM48+Qx4F8RKf0T2RlQN1XZ4sJyCN4syfpLeMXN3Y6hvmAoiHA1P/CR44rLO39RRVU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nw6QVtQR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nw6QVtQR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9BF3C2BBFC; Mon, 17 Jun 2024 01:49:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718589002; bh=NheZlQukXrHe+aAqSQt20W9ihRV2X4255gLoqcg7brw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nw6QVtQRaoS4WUF3g1P6l1m+RA1PnZV72WOfiuhHMQp2RepZEjWMZ+p+eLz3++27w wp8bfJ4EYJ7in0idip8Tj0CEV9qQQUwogJV7/T6iPOji2mfuLz2CW93nEojZU0B0OJ JCkzRoSzxyVPinmUibxs3zSKwj+ws10ssP3n0YxfG6bZ+HIqkn9MTBrX5H9+NVR6mz 1lzMfJAwoufluGbRrI0tYSOMO5mwR/sirD7eTz+m65rZD8nEudr9pBAOEp6l6UyOV7 SS1fAcSvHirzNREvkPr2e8rXB8uaGhn1Ae/nZVHrHDsSBSuCTwJN93DxMd1t/vn9kK BcVx7Bnwhq5uA== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v11 18/18] fgraph: Skip recording calltime/rettime if it is not nneeded Date: Mon, 17 Jun 2024 10:49:56 +0900 Message-Id: <171858899671.288820.1294786279157013093.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171858878797.288820.237119113242007537.stgit@devnote2> References: <171858878797.288820.237119113242007537.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Masami Hiramatsu (Google) Skip recording calltime and rettime if the fgraph_ops does not need it. This is a kind of performance optimization for fprobe. Since the fprobe user does not use these entries, recording timestamp in fgraph is just a overhead (e.g. eBPF, ftrace). So introduce the skip_timestamp flag, and all fgraph_ops sets this flag, skip recording calltime and rettime. Suggested-by: Jiri Olsa Signed-off-by: Masami Hiramatsu (Google) --- Changes in v11: - Simplify it to be symmetric on push and pop. (Thus the timestamp getting place is a bit shifted.) Changes in v10: - Add likely() to skipping timestamp. Changes in v9: - Newly added. --- include/linux/ftrace.h | 2 ++ kernel/trace/fgraph.c | 36 +++++++++++++++++++++++++++++++++--- kernel/trace/fprobe.c | 1 + 3 files changed, 36 insertions(+), 3 deletions(-) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index d8a58b940d81..fabf1a0979d4 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -1160,6 +1160,8 @@ struct fgraph_ops { void *private; trace_func_graph_ent_t saved_func; int idx; + /* If skip_timestamp is true, this does not record timestamps. */ + bool skip_timestamp; }; void *fgraph_reserve_data(int idx, int size_bytes); diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index d735a8c872bb..cf3ae59a436e 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -174,6 +174,7 @@ int ftrace_graph_active; static struct fgraph_ops *fgraph_array[FGRAPH_ARRAY_SIZE]; static unsigned long fgraph_array_bitmask; +static bool fgraph_skip_timestamp; /* LRU index table for fgraph_array */ static int fgraph_lru_table[FGRAPH_ARRAY_SIZE]; @@ -557,7 +558,11 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, return -EBUSY; } - calltime = trace_clock_local(); + /* This is not really 'likely' but for keeping the least path to be faster. */ + if (likely(fgraph_skip_timestamp)) + calltime = 0LL; + else + calltime = trace_clock_local(); offset = READ_ONCE(current->curr_ret_stack); ret_stack = RET_STACK(current, offset); @@ -728,6 +733,12 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, *ret = ret_stack->ret; trace->func = ret_stack->func; trace->calltime = ret_stack->calltime; + /* This is not really 'likely' but for keeping the least path to be faster. */ + if (likely(!trace->calltime)) + trace->rettime = 0LL; + else + trace->rettime = trace_clock_local(); + trace->overrun = atomic_read(¤t->trace_overrun); trace->depth = current->curr_ret_depth; /* @@ -788,7 +799,6 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe return (unsigned long)panic; } - trace.rettime = trace_clock_local(); if (fregs) ftrace_regs_set_instruction_pointer(fregs, ret); @@ -1242,6 +1252,24 @@ static void ftrace_graph_disable_direct(bool disable_branch) fgraph_direct_gops = &fgraph_stub; } +static void update_fgraph_skip_timestamp(void) +{ + int i; + + for (i = 0; i < FGRAPH_ARRAY_SIZE; i++) { + struct fgraph_ops *gops = fgraph_array[i]; + + if (gops == &fgraph_stub) + continue; + + if (!gops->skip_timestamp) { + fgraph_skip_timestamp = false; + return; + } + } + fgraph_skip_timestamp = true; +} + int register_ftrace_graph(struct fgraph_ops *gops) { int command = 0; @@ -1267,6 +1295,7 @@ int register_ftrace_graph(struct fgraph_ops *gops) gops->idx = i; ftrace_graph_active++; + update_fgraph_skip_timestamp(); if (ftrace_graph_active == 2) ftrace_graph_disable_direct(true); @@ -1298,6 +1327,7 @@ int register_ftrace_graph(struct fgraph_ops *gops) ftrace_graph_active--; gops->saved_func = NULL; fgraph_lru_release_index(i); + update_fgraph_skip_timestamp(); } out: mutex_unlock(&ftrace_lock); @@ -1321,8 +1351,8 @@ void unregister_ftrace_graph(struct fgraph_ops *gops) goto out; fgraph_array[gops->idx] = &fgraph_stub; - ftrace_graph_active--; + update_fgraph_skip_timestamp(); if (!ftrace_graph_active) command = FTRACE_STOP_FUNC_RET; diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index afa52d9816cf..24bb8edec8a3 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -345,6 +345,7 @@ NOKPROBE_SYMBOL(fprobe_return); static struct fgraph_ops fprobe_graph_ops = { .entryfunc = fprobe_entry, .retfunc = fprobe_return, + .skip_timestamp = true, }; static int fprobe_graph_active;