From patchwork Fri Jan 12 10:15:11 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: 13518226 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 CB601634EE; Fri, 12 Jan 2024 10:15:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="sVs+ZWkM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 05811C433C7; Fri, 12 Jan 2024 10:15:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705054517; bh=ZExIjzlvIHiWOr1SWHx178nMkcePO/iYDVrSnbmxavo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sVs+ZWkM1z2tZNZ+DnjZcn4KBCmQXe8N3q4G8eQ+q6OdSwvnloEPXyrLXFTIPgN4n 8Ri7fORdA5IWI9/KsGqyb6fAvooX1+QJ6ncqYD0a4cm2cs36b1e986EvuCcLO4OaQj lCJcvhjsM9FZVtRPJwt4ucfglRpOnzpt9P49RoF5ZEh3SuEaXQ/0j9hw8XXK2dyyfh PWIyyWI8Gbr7nagl/T8UOdeN/881YeZjANEpPZUY2jGGK9U6oM/sqzpLzzun/4k8Fm MTckFwCwltcO1B9EYotz0ULQBM0sPYA5O0L6vZbolKP9S3M6f+6KcHUCTQY9mDISVL Mc7OLxyF88Hzg== 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 v6 22/36] function_graph: Add a new entry handler with parent_ip and ftrace_regs Date: Fri, 12 Jan 2024 19:15:11 +0900 Message-Id: <170505451140.459169.10466274060076226583.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <170505424954.459169.10630626365737237288.stgit@devnote2> References: <170505424954.459169.10630626365737237288.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 a new entry handler to fgraph_ops as 'entryregfunc' which takes parent_ip and ftrace_regs. Note that the 'entryfunc' and 'entryregfunc' are mutual exclusive. You can set only one of them. Signed-off-by: Masami Hiramatsu (Google) --- Changes in v3: - Update for new multiple fgraph. --- arch/arm64/kernel/ftrace.c | 2 + arch/loongarch/kernel/ftrace_dyn.c | 6 ++++ arch/powerpc/kernel/trace/ftrace.c | 2 + arch/powerpc/kernel/trace/ftrace_64_pg.c | 10 ++++--- arch/x86/kernel/ftrace.c | 42 ++++++++++++++++-------------- include/linux/ftrace.h | 19 +++++++++++--- kernel/trace/fgraph.c | 30 +++++++++++++++++---- 7 files changed, 76 insertions(+), 35 deletions(-) diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index b96740829798..779b975f03f5 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -497,7 +497,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, return; if (!function_graph_enter_ops(*parent, ip, frame_pointer, - (void *)frame_pointer, gops)) + (void *)frame_pointer, fregs, gops)) *parent = (unsigned long)&return_to_handler; ftrace_test_recursion_unlock(bit); diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c index 73858c9029cc..39b3f09a5e0c 100644 --- a/arch/loongarch/kernel/ftrace_dyn.c +++ b/arch/loongarch/kernel/ftrace_dyn.c @@ -244,7 +244,11 @@ 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]; - prepare_ftrace_return(ip, (unsigned long *)parent); + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + if (!function_graph_enter_regs(regs->regs[1], ip, 0, parent, fregs)) + regs->regs[1] = (unsigned long)&return_to_handler; } #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 82010629cf88..9bf1b6912116 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -422,7 +422,7 @@ 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 7b85c3b460a3..43f6cfaaf7db 100644 --- a/arch/powerpc/kernel/trace/ftrace_64_pg.c +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c @@ -795,7 +795,8 @@ 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; @@ -812,7 +813,7 @@ __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); @@ -824,13 +825,14 @@ __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/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 845e29b4254f..0f757e399a96 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -614,16 +614,8 @@ 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, @@ -633,13 +625,28 @@ 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; +} - if (unlikely(atomic_read(¤t->tracing_graph_pause))) +/* + * 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(skip_ftrace_return())) return; bit = ftrace_test_recursion_trylock(ip, *parent); @@ -661,17 +668,14 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct fgraph_ops *gops = container_of(op, struct fgraph_ops, ops); int bit; - if (unlikely(ftrace_graph_is_dead())) - return; - - if (unlikely(atomic_read(¤t->tracing_graph_pause))) + if (unlikely(skip_ftrace_return())) return; bit = ftrace_test_recursion_trylock(ip, *parent); if (bit < 0) return; - if (!function_graph_enter_ops(*parent, ip, 0, parent, gops)) + if (!function_graph_enter_ops(*parent, ip, 0, parent, fregs, gops)) *parent = (unsigned long)&return_to_handler; ftrace_test_recursion_unlock(bit); diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 815e865f46c9..65d4d4b68768 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -1063,6 +1063,11 @@ typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *, typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *, struct fgraph_ops *); /* entry */ +typedef int (*trace_func_graph_regs_ent_t)(unsigned long func, + unsigned long parent_ip, + struct ftrace_regs *fregs, + struct fgraph_ops *); /* entry w/ regs */ + extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph_ops *gops); #ifdef CONFIG_FUNCTION_GRAPH_TRACER @@ -1070,6 +1075,7 @@ extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph struct fgraph_ops { trace_func_graph_ent_t entryfunc; trace_func_graph_ret_t retfunc; + trace_func_graph_regs_ent_t entryregfunc; struct ftrace_ops ops; /* for the hash lists */ void *private; int idx; @@ -1106,13 +1112,20 @@ 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); +} extern int function_graph_enter_ops(unsigned long ret, unsigned long func, unsigned long frame_pointer, unsigned long *retp, - struct fgraph_ops *gops); + struct ftrace_regs *fregs, struct fgraph_ops *gops); struct ftrace_ret_stack * ftrace_graph_get_ret_stack(struct task_struct *task, int idx); diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 6a9206ebc6a2..0cb02de2db70 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -621,9 +621,21 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, # define MCOUNT_INSN_SIZE 0 #endif +static inline int call_entry_func(struct ftrace_graph_ent *trace, + unsigned long func, unsigned long ret, + struct ftrace_regs *fregs, + struct fgraph_ops *gops) +{ + if (gops->entryregfunc) + return gops->entryregfunc(func, ret, fregs, gops); + + return gops->entryfunc(trace, gops); +} + /* 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; @@ -658,7 +670,7 @@ 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)) + call_entry_func(&trace, func, ret, fregs, gops)) bitmap |= BIT(i); else /* Clear out any saved storage */ @@ -686,6 +698,7 @@ int function_graph_enter(unsigned long ret, unsigned long func, /* This is called from ftrace_graph_func() via ftrace */ int function_graph_enter_ops(unsigned long ret, unsigned long func, unsigned long frame_pointer, unsigned long *retp, + struct ftrace_regs *fregs, struct fgraph_ops *gops) { struct ftrace_graph_ent trace; @@ -710,7 +723,7 @@ int function_graph_enter_ops(unsigned long ret, unsigned long func, trace.func = func; trace.depth = current->curr_ret_depth; save_curr_ret_stack = current->curr_ret_stack; - if (gops->entryfunc(&trace, gops)) { + if (call_entry_func(&trace, func, ret, fregs, gops)) { if (type == FGRAPH_TYPE_RESERVED) set_fgraph_index_bitmap(current, index, BIT(gops->idx)); else @@ -993,7 +1006,8 @@ void fgraph_init_ops(struct ftrace_ops *dst_ops, struct ftrace_ops *src_ops) { dst_ops->func = ftrace_graph_func; - 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 FTRACE_GRAPH_TRAMP_ADDR dst_ops->trampoline = FTRACE_GRAPH_TRAMP_ADDR; @@ -1239,10 +1253,14 @@ int register_ftrace_graph(struct fgraph_ops *gops) int ret = 0; int i; + if (gops->entryfunc && gops->entryregfunc) + return -EINVAL; + mutex_lock(&ftrace_lock); if (!gops->ops.func) { - gops->ops.flags |= FTRACE_OPS_GRAPH_STUB; + gops->ops.flags |= FTRACE_OPS_GRAPH_STUB | + FTRACE_OPS_FL_SAVE_ARGS; gops->ops.func = ftrace_graph_func; #ifdef FTRACE_GRAPH_TRAMP_ADDR gops->ops.trampoline = FTRACE_GRAPH_TRAMP_ADDR;