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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFA76C7EE37 for ; Fri, 9 Jun 2023 01:58:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237773AbjFIB6p (ORCPT ); Thu, 8 Jun 2023 21:58:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238057AbjFIB6n (ORCPT ); Thu, 8 Jun 2023 21:58:43 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55C6430C5; Thu, 8 Jun 2023 18:58:40 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D580E61AFB; Fri, 9 Jun 2023 01:58:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DF6BC433EF; Fri, 9 Jun 2023 01:58:36 +0000 (UTC) Date: Thu, 8 Jun 2023 21:58:34 -0400 From: Steven Rostedt To: Donglin Peng Cc: mhiramat@kernel.org, linux@armlinux.org.uk, mark.rutland@arm.com, will@kernel.org, catalin.marinas@arm.com, rmk+kernel@armlinux.org.uk, palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu, tglx@linutronix.de, dave.hansen@linux.intel.com, x86@kernel.org, bp@alien8.de, hpa@zytor.com, chenhuacai@kernel.org, zhangqing@loongson.cn, kernel@xen0n.name, mingo@redhat.com, peterz@infradead.org, xiehuan09@gmail.com, dinghui@sangfor.com.cn, huangcun@sangfor.com.cn, dolinux.peng@gmail.com, linux-trace-kernel@vger.kernel.org, loongarch@lists.linux.dev, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v11 5/8] riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL Message-ID: <20230608215834.729cfda2@gandalf.local.home> In-Reply-To: References: 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 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org Can I get an ack from a RISC-V maintainer? -- Steve On Sat, 8 Apr 2023 05:42:19 -0700 Donglin Peng wrote: > The previous patch ("function_graph: Support recording and printing > the return value of function") has laid the groundwork for the for > the funcgraph-retval, and this modification makes it available on > the RISC-V platform. > > We introduce a new structure called fgraph_ret_regs for the RISC-V > platform to hold return registers and the frame pointer. We then > fill its content in the return_to_handler and pass its address to > the function ftrace_return_to_handler to record the return value. > > Signed-off-by: Donglin Peng > --- > v10: > - Use CONFIG_FUNCTION_GRAPH_TRACER to control fgraph_ret_regs definition > > v9: > - Update the commit message > > v8: > - Modify the control range of CONFIG_HAVE_FUNCTION_GRAPH_RETVAL > --- > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/ftrace.h | 21 +++++++++++++++++++++ > arch/riscv/kernel/mcount.S | 7 +------ > 3 files changed, 23 insertions(+), 6 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index eb7f29a412f8..108538815309 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -139,6 +139,7 @@ config RISCV > select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8) > select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE > select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL > + select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER > select HAVE_FUNCTION_GRAPH_TRACER > select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION > > diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h > index d47d87c2d7e3..740a979171e5 100644 > --- a/arch/riscv/include/asm/ftrace.h > +++ b/arch/riscv/include/asm/ftrace.h > @@ -111,4 +111,25 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); > > #endif /* CONFIG_DYNAMIC_FTRACE */ > > +#ifndef __ASSEMBLY__ > +#ifdef CONFIG_FUNCTION_GRAPH_TRACER > +struct fgraph_ret_regs { > + unsigned long a1; > + unsigned long a0; > + unsigned long s0; > + unsigned long ra; > +}; > + > +static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) > +{ > + return ret_regs->a0; > +} > + > +static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) > +{ > + return ret_regs->s0; > +} > +#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ > +#endif > + > #endif /* _ASM_RISCV_FTRACE_H */ > diff --git a/arch/riscv/kernel/mcount.S b/arch/riscv/kernel/mcount.S > index 30102aadc4d7..8a6e5a9e842a 100644 > --- a/arch/riscv/kernel/mcount.S > +++ b/arch/riscv/kernel/mcount.S > @@ -65,13 +65,8 @@ ENTRY(return_to_handler) > * So alternatively we check the *old* frame pointer position, that is, the > * value stored in -16(s0) on entry, and the s0 on return. > */ > -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST > - mv t6, s0 > -#endif > SAVE_RET_ABI_STATE > -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST > - mv a0, t6 > -#endif > + mv a0, sp > call ftrace_return_to_handler > mv a2, a0 > RESTORE_RET_ABI_STATE