From patchwork Mon Apr 15 12:54:18 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: 13629967 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 164D273510; Mon, 15 Apr 2024 12:54:24 +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=1713185664; cv=none; b=eR3RH2Mlj1kTEbflQJXp91MFzNkrBdrfnQXOTlKds+rVZoa9KrcBwfsNp4w2pTqRdex65wpVNwXIRR0ckD4At1KBrozXFyB//xKEnZXzL6chCc6qqvADEkA9mA2RL7fo3eAmQH0FPaaRAc5+cOJOj/udWjEuEdy8rmERUm9iCkI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713185664; c=relaxed/simple; bh=gNJjJA1acpKJM9emKColJP4uw+0aSERwNgAog+Jp7cA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=IoP7kW+uJp1FijbBrIRgShoQ+q4lLkWt3//UfsOOGmdl3ZqxoUrqmugFXhzPVroOLAwvz5Hufd2Ar144o+ZL3Lr+X2NhgqVI5IMWRm2Hf00JaIuDlj7TNKuLOSO6w2MJ9BFGD2innbwRbpyu9p30xKXelbgOGaauUMJPz5OI5hY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K7oJYNzd; 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="K7oJYNzd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 43C92C2BD11; Mon, 15 Apr 2024 12:54:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713185664; bh=gNJjJA1acpKJM9emKColJP4uw+0aSERwNgAog+Jp7cA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=K7oJYNzdhhAS34heQavME/jheWsdSlA6n6ezqZiSZE1syFHEga+QYfBkh846Sd7Qw aYRIA4Ow4DSWUkgQEnHKHMGh1MiHK7bu8RhAfTAaPYsLXCg6ncZEO1BJvpl7fM/uGU u/fI9hrqWYfu6d8ptwzBtVQUpnSo2RJxA6qlmTMLbmj4D0b7RsCUx/dbg8iN0QSKhd 8eHDTY0XUl9FYijJQPZhYfe8QPWzzPFMF6ScKOQNpLYVK8EzLgdqWDZX1/+jOVsqed rHoWXlY0d2JjU+kK5T5+mmU+e4qso/mBSbV4M8P937VfNiwZdaYPk8+KON+WSbeGvq W6RExyJMNyKRg== 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 v9 27/36] tracing: Add ftrace_fill_perf_regs() for perf event Date: Mon, 15 Apr 2024 21:54:18 +0900 Message-Id: <171318565784.254850.13623675081841077242.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <171318533841.254850.15841395205784342850.stgit@devnote2> References: <171318533841.254850.15841395205784342850.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 aab2b7a0f78c..95a8f349f871 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -154,6 +154,13 @@ 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 cfec6c5a47d0..51245fd6b45b 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -44,6 +44,13 @@ 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 9f8cc6d13bec..cb8d60a5fe1d 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -89,6 +89,11 @@ 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 8d6db2b7d03a..7625887fc49b 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -54,6 +54,13 @@ 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 9cf4c1b8b3f8..71dd25afdb1c 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -194,6 +194,37 @@ 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.