From mboxrd@z Thu Jan 1 00:00:00 1970 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 D19242CA6; Sun, 15 Sep 2024 09:22:13 +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=1726392133; cv=none; b=fpug2wUgLkGQDdUQkpcJIv0wQU3YJ8JNofuD5JyoqVfWl0z+Kniwy76gLprtbIcY0LJ+iUC0S9FxsnC4pkS5YXkTCeD7DU44Zx7kliRMuECdffkz8fWfpHl0IQhXvULy9Ehq0ihRTzANNAVnMlyBj6vZLIiaPpRL8CDe54BiX14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726392133; c=relaxed/simple; bh=hlKhojcEd9iQsGKbuSqGRPSfk4f5cdS8JzNz7/1tFxc=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=VWWYHea5j2gHXjXPvWtKekh2KqKRfAISsxMSnyMWHgKw4ZuqCrc3fiaJSk5dln8ery1mqpdbB/4YGBmaSVDGUouQtvVDagIydePm1GycWZwA/WwtW9XuZdjJ+fmeInzBs2zokS+ZT19MF7NFfvsVWqRX+T/M2rA3Yw/S8FYcxWU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 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) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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.