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 9AB13C433F5 for ; Tue, 22 Mar 2022 12:48:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235038AbiCVMtm (ORCPT ); Tue, 22 Mar 2022 08:49:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233454AbiCVMtj (ORCPT ); Tue, 22 Mar 2022 08:49:39 -0400 Received: from mail-pl1-x629.google.com (mail-pl1-x629.google.com [IPv6:2607:f8b0:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4EBC632A for ; Tue, 22 Mar 2022 05:48:11 -0700 (PDT) Received: by mail-pl1-x629.google.com with SMTP id n15so15373978plh.2 for ; Tue, 22 Mar 2022 05:48:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=DpDIKrRxxH2uk4JPff6xIxmueMX+SFTxFN5YBUfx1gk=; b=teSMCHM4MFOGwL4r7o4k0jzZn6iFzq3bxIHbT6KSdd7ae6eNBGBYHLyg9DA9+RLypq 6/xKa6U/qR1w1cYJnqgjDAEw4jUDc1Hk+3z2UyI37JwaLBMvmyHHRTi67RW6RNPP1Sj+ /OCSIQRMzsz4xLYjW2IlNMV4WKZKnGVE6afY9Dqj59LbJlEqcTAD96M6/NgCD46ja50T A9GdFv3jCIwejoGoeFrfVFdkwMYntoWS1Doy/a7AAuUhOCFoT0TzyzZBudNn60+zolh+ XVrsckmiPwpbakATT910eUPj3kSCOV++rcC41ZLQ/6zR8ycv1s9cAK4SgJlzfOHSL3a1 jeLQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=DpDIKrRxxH2uk4JPff6xIxmueMX+SFTxFN5YBUfx1gk=; b=TJSzOZwvq3pZfi9tRABwgzVQutIh6Q2H1940lnGsoToNwNELyvt0e2qrgOSuYCHl5T 21Cre4E15dGVC7e3kZzTUs7BO0LE++R4hYPjB5b47pF86EZF6R2YuIyjwpfs2kzgWMAf sUnhTmVr7Phy3XFeT7gkbmwbqMYXxFicIXnVO9UD8691Hg4VLhuJEZTUAedK1X+SPCfZ E7vhKRwPPQ5njDLdRpqtWf2QBcHU8BQy87Yu3eGx7pw61wd2OZEkgOxF4/xVnn7vX+yk khe2hGa0Hk6s9t5pl/ydzitqjWriDIhu13R+6ksJMmCjoDnDShpXaFp7SmGgiX5CuOHO yx+Q== X-Gm-Message-State: AOAM531qN1q0061saUL+4JpjQhRthWT7OE0wE3SoVUgQzztTEo9ePkwB vKRjKP6y/DveUgeMO/37n+kY0w== X-Google-Smtp-Source: ABdhPJzFrAYkcOTj9IlEDLm6FVFNaE9DmJSyjdtzg9Iu0ju/nE6/6Or3iZ867JywlHwjYXFDgTjKgA== X-Received: by 2002:a17:902:7002:b0:14d:76b9:2303 with SMTP id y2-20020a170902700200b0014d76b92303mr18381725plk.155.1647953290743; Tue, 22 Mar 2022 05:48:10 -0700 (PDT) Received: from ?IPV6:2409:8a28:e62:3990:ac62:e5ec:7f4f:1b38? ([2409:8a28:e62:3990:ac62:e5ec:7f4f:1b38]) by smtp.gmail.com with ESMTPSA id t10-20020a056a00138a00b004fa9c9fda44sm8560181pfg.89.2022.03.22.05.48.06 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 22 Mar 2022 05:48:10 -0700 (PDT) Message-ID: Date: Tue, 22 Mar 2022 20:48:00 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH v3 3/3] arm64/ftrace: Make function graph use ftrace directly Content-Language: en-US To: rostedt@goodmis.org, mark.rutland@arm.com, mingo@redhat.com, tglx@linutronix.de, catalin.marinas@arm.com, will@kernel.org, dave.hansen@linux.intel.com, broonie@kernel.org Cc: x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, songmuchun@bytedance.com, qirui.001@bytedance.com References: <20220224093251.49971-1-zhouchengming@bytedance.com> <20220224093251.49971-3-zhouchengming@bytedance.com> From: Chengming Zhou In-Reply-To: <20220224093251.49971-3-zhouchengming@bytedance.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, ping... have any comments? Thanks. On 2022/2/24 5:32 下午, Chengming Zhou wrote: > As we do in commit 0c0593b45c9b ("x86/ftrace: Make function graph > use ftrace directly"), we don't need special hook for graph tracer, > but instead we use graph_ops:func function to install return_hooker. > > Since commit 3b23e4991fb6 ("arm64: implement ftrace with regs") add > implementation for FTRACE_WITH_REGS on arm64, we can easily adopt > the same cleanup on arm64. And this cleanup only changes the > FTRACE_WITH_REGS implementation, so the mcount-based implementation > is unaffected. > > Signed-off-by: Chengming Zhou > --- > Changes in v3: > - Add comments in ftrace_graph_func() as suggested by Steve. > > Changes in v2: > - Remove FTRACE_WITH_REGS ftrace_graph_caller asm as suggested by Mark. > --- > arch/arm64/include/asm/ftrace.h | 7 +++++++ > arch/arm64/kernel/entry-ftrace.S | 17 ----------------- > arch/arm64/kernel/ftrace.c | 17 +++++++++++++++++ > 3 files changed, 24 insertions(+), 17 deletions(-) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index 1494cfa8639b..dbc45a4157fa 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -80,8 +80,15 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) > > #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > struct dyn_ftrace; > +struct ftrace_ops; > +struct ftrace_regs; > + > int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); > #define ftrace_init_nop ftrace_init_nop > + > +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > + struct ftrace_ops *op, struct ftrace_regs *fregs); > +#define ftrace_graph_func ftrace_graph_func > #endif > > #define ftrace_return_address(n) return_address(n) > diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S > index e535480a4069..d42a205ef625 100644 > --- a/arch/arm64/kernel/entry-ftrace.S > +++ b/arch/arm64/kernel/entry-ftrace.S > @@ -97,12 +97,6 @@ SYM_CODE_START(ftrace_common) > SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) > bl ftrace_stub > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > -SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) // ftrace_graph_caller(); > - nop // If enabled, this will be replaced > - // "b ftrace_graph_caller" > -#endif > - > /* > * At the callsite x0-x8 and x19-x30 were live. Any C code will have preserved > * x19-x29 per the AAPCS, and we created frame records upon entry, so we need > @@ -127,17 +121,6 @@ ftrace_common_return: > ret x9 > SYM_CODE_END(ftrace_common) > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > -SYM_CODE_START(ftrace_graph_caller) > - ldr x0, [sp, #S_PC] > - sub x0, x0, #AARCH64_INSN_SIZE // ip (callsite's BL insn) > - add x1, sp, #S_LR // parent_ip (callsite's LR) > - ldr x2, [sp, #PT_REGS_SIZE] // parent fp (callsite's FP) > - bl prepare_ftrace_return > - b ftrace_common_return > -SYM_CODE_END(ftrace_graph_caller) > -#endif > - > #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > > /* > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c > index 4506c4a90ac1..35eb7c9b5e53 100644 > --- a/arch/arm64/kernel/ftrace.c > +++ b/arch/arm64/kernel/ftrace.c > @@ -268,6 +268,22 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, > } > > #ifdef CONFIG_DYNAMIC_FTRACE > + > +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > + struct ftrace_ops *op, struct ftrace_regs *fregs) > +{ > + /* > + * Athough graph_ops doesn't have FTRACE_OPS_FL_SAVE_REGS set in flags, > + * regs can't be NULL in DYNAMIC_FTRACE_WITH_REGS. By design, it should > + * be fixed when DYNAMIC_FTRACE_WITH_ARGS is implemented. > + */ > + struct pt_regs *regs = arch_ftrace_get_regs(fregs); > + unsigned long *parent = (unsigned long *)&procedure_link_pointer(regs); > + > + prepare_ftrace_return(ip, parent, frame_pointer(regs)); > +} > +#else > /* > * Turn on/off the call to ftrace_graph_caller() in ftrace_caller() > * depending on @enable. > @@ -297,5 +313,6 @@ int ftrace_disable_ftrace_graph_caller(void) > { > return ftrace_modify_graph_caller(false); > } > +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > #endif /* CONFIG_DYNAMIC_FTRACE */ > #endif /* CONFIG_FUNCTION_GRAPH_TRACER */