From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 48B5BC35FE8 for ; Sun, 15 Sep 2024 09:23:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=QmJKoVMv5jYR6k3hIpSZak+Gz27Sz8Qc2nFxG/Qubv8=; b=cF26euQh1bDuyNJg6gOrr1FG+y R1E+25mQnYFp/eA3vQDG9KD5w27GIbcsXM9uIVhoLxcPQfOvi+EM6cSmKE1lmnu/38mOEyM5+IIyC ePlzJb9lAxlaHyO10mNd6048d6FisLLHgAy2viyxJhElRpgB9ifz5k9OebC9AxWeGFb/LmSls06YF ZnalqKQnqP0k/8x4ounMyLnenghpQQzY25ayC/1PfNZljRg6Xb0z1/ZbqmIFAT6jvBBdmXkw7Q4FU 7gzXS3GkWmLAFh3yzq2UQPi/JWASmqG4lcPUTY8THhqizgIBRl4VBiK4WWDDp/K5DWgsSfDsf4mMB +L7kMukQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1splTW-00000001uYe-38VR; Sun, 15 Sep 2024 09:23:22 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1splSQ-00000001uLD-2vI8 for linux-arm-kernel@lists.infradead.org; Sun, 15 Sep 2024 09:22:16 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 00F7DA40D42; Sun, 15 Sep 2024 09:22:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 298DFC4CEC3; Sun, 15 Sep 2024 09:22:09 +0000 (UTC) Date: Sun, 15 Sep 2024 05:22:04 -0400 From: Steven Rostedt To: Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org Cc: "Masami Hiramatsu (Google)" , Florent Revest , linux-trace-kernel@vger.kernel.org, LKML , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Mark Rutland Subject: Re: [PATCH v14 08/19] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs Message-ID: <20240915052204.3dff1f75@rorschach.local.home> In-Reply-To: <172615377576.133222.5911358383330497277.stgit@devnote2> References: <172615368656.133222.2336770908714920670.stgit@devnote2> <172615377576.133222.5911358383330497277.stgit@devnote2> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240915_022214_898172_1C7D8C4C X-CRM114-Status: GOOD ( 27.03 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Can I get an Acked-by from the AARCH64 maintainers for this patch? Thanks! -- Steve On Fri, 13 Sep 2024 00:09:35 +0900 "Masami Hiramatsu (Google)" wrote: > 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 v14: > - Add riscv change. > 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 +++++++++++ > arch/riscv/include/asm/ftrace.h | 12 ++++++++++++ > include/linux/ftrace.h | 17 +++++++++++++++++ > 3 files changed, 40 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/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h > index e9f364ce9fe8..897779dec402 100644 > --- a/arch/riscv/include/asm/ftrace.h > +++ b/arch/riscv/include/asm/ftrace.h > @@ -193,6 +193,18 @@ static __always_inline void ftrace_override_function_with_return(struct ftrace_r > fregs->epc = fregs->ra; > } > > +static __always_inline struct pt_regs * > +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > +{ > + memcpy(®s->a0, fregs->args, sizeof(u64) * 8); > + regs->epc = fregs->epc; > + regs->ra = fregs->ra; > + regs->sp = fregs->sp; > + regs->s0 = fregs->s0; > + regs->t1 = fregs->t1; > + return regs; > +} > + > int ftrace_regs_query_register_offset(const char *name); > > void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index a1b2ef492c7f..bd9a26bdf660 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.