From patchwork Thu Sep 12 15:09:47 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: 13802259 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 6697E1B1D60; Thu, 12 Sep 2024 15:09:53 +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=1726153793; cv=none; b=lOC20kpDOv/QWlj+VFlR8q6FURTz9x4gyzBD/BNGgZ+TjFn2NwEliDy3RxXGJ75sZIpdE6nj6zxs6o8hzWeiLX112iA3boKbVreTYvz53v2ZLxYtDP7tMRMGnYGOBiXSEhUA51o7+0nHkPjmtSx2+YXcEE0J1LbZBDoQUBV9O74= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726153793; c=relaxed/simple; bh=oM/kSUbxch3kFN7tAWfFFjXUCrxI3kpMjYUsuujPY5Q=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=pawsPKBguZVEA7WVQ20Z9jZKET5YSs7PiqrKgn49cOWwk4UVgRKD6cRE7v3j6m5rqFiUfgh4GGgEfcZgv7ZTL3gFR8F5fMXrZGhd+vehz74W9hihIInUqHJ91cUp0kwRXVP0nJPyfMLesejfuzyY1PnrLcqHs2P2LOSbadnoKWo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fuaDHqPK; 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="fuaDHqPK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B172C4CEC3; Thu, 12 Sep 2024 15:09:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726153793; bh=oM/kSUbxch3kFN7tAWfFFjXUCrxI3kpMjYUsuujPY5Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fuaDHqPKncdgkc8FaGKCeDoQV3HwqCSeCH2W1t1/AgquSqjJmwymNAcfvK23iWVNp /hhqxFEIrmnSbhz9bpJcOVH2767KYnvW3TETMq71t1GbL8Ay91eq6ZbGi0i4K+cKyC P5FpJLT0GraG+Y9G7TBrNJDtYrPG+LEZl4MY1wSuTogGAUkmYwWYeq0MqS5GupRhzz EmA1m40NgU1ITS2yEuOI/HlHDX9azBdTFdsRqi7HXs4R/mYJZOdVtJcOwI99XTIGrX lPC5dFM6nLj+Lh7qp22HTjmQCycOyKxecrqGqDFZY+Y/SxwmlA2Jwf0JuxGcqbWIPp 34svXkvWFnbnA== 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 , linux-arch@vger.kernel.org Subject: [PATCH v14 09/19] tracing: Add ftrace_fill_perf_regs() for perf event Date: Fri, 13 Sep 2024 00:09:47 +0900 Message-Id: <172615378702.133222.3149457339191866610.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <172615368656.133222.2336770908714920670.stgit@devnote2> References: <172615368656.133222.2336770908714920670.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 bd9a26bdf660..3edf2427ae73 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.