From nobody Mon Sep 15 12:59:21 2025 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 0A32BC54EBC for ; Thu, 12 Jan 2023 09:13:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239980AbjALJNG (ORCPT ); Thu, 12 Jan 2023 04:13:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235788AbjALJKh (ORCPT ); Thu, 12 Jan 2023 04:10:37 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F6B6B29 for ; Thu, 12 Jan 2023 01:06:40 -0800 (PST) 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 sin.source.kernel.org (Postfix) with ESMTPS id 6C17CCE1DC0 for ; Thu, 12 Jan 2023 09:06:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B589DC433EF; Thu, 12 Jan 2023 09:06:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673514396; bh=AcQPMa1xem2L3CVjL895ndWZGRAVPIn0wP4CjkQEVMk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nGcVfVuAHS8L4n67pfSMSIheXgKu9fPNcNblTy0bKS2AiVLCU0UV8BrBfDmGsy1xB KoLJG1iDQPNCPJGKAOJUpZ8lAZKBfZQvl3mapjjNB04r+j8UTKmM8Di8oZrSjlChF2 KUrJ5G4oWdBHV244mKLLbBY6A0aYHaZ4u/YyEP9RD3C4ITqkC2tXVibQuxDKbZGglY aJKGfqn79RdpUYPTrJnPmz4dXXAeoUZoxGGPmTfz+I2ZGuTzrKvhTj2kh2AhKhOpyn MKNwSU/XVW+Se8+U1GUXSyVCLmjmH6JlhVYI2ISw5fmJu6vDS162K8qsw4eVX4YvBO K6pT22v2NUC0g== From: guoren@kernel.org To: anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, conor.dooley@microchip.com, heiko@sntech.de, rostedt@goodmis.org, mhiramat@kernel.org, jolsa@redhat.com, bp@suse.de, jpoimboe@kernel.org, suagrfillet@gmail.com, andy.chiu@sifive.com, e.shatokhin@yadro.com, guoren@kernel.org Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH -next V7 4/7] riscv: ftrace: Add ftrace_graph_func Date: Thu, 12 Jan 2023 04:06:00 -0500 Message-Id: <20230112090603.1295340-5-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20230112090603.1295340-1-guoren@kernel.org> References: <20230112090603.1295340-1-guoren@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Song Shuai Here implements ftrace_graph_func as the function graph tracing function with FTRACE_WITH_REGS defined. function_graph_func gets the point of the parent IP and the frame pointer from fregs and call prepare_ftrace_return for function graph tracing. If FTRACE_WITH_REGS isn't defined, the enable/disable helpers of ftrace_graph_[regs]_call are revised for serving only ftrace_graph_call in the !FTRACE_WITH_REGS version ftrace_caller. Signed-off-by: Song Shuai Tested-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/include/asm/ftrace.h | 13 ++- arch/riscv/kernel/ftrace.c | 30 +++---- arch/riscv/kernel/mcount-dyn.S | 139 +++++++++++++++++++++++--------- 3 files changed, 126 insertions(+), 56 deletions(-) diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrac= e.h index 9e73922e1e2e..84f856a3286e 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -107,8 +107,17 @@ do { \ struct dyn_ftrace; int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); #define ftrace_init_nop ftrace_init_nop -#endif =20 -#endif +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +struct ftrace_ops; +struct ftrace_regs; +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 /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ + +#endif /* __ASSEMBLY__ */ + +#endif /* CONFIG_DYNAMIC_FTRACE */ =20 #endif /* _ASM_RISCV_FTRACE_H */ diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c index 5bff37af4770..95e14d8161a4 100644 --- a/arch/riscv/kernel/ftrace.c +++ b/arch/riscv/kernel/ftrace.c @@ -169,32 +169,28 @@ void prepare_ftrace_return(unsigned long *parent, uns= igned long self_addr, } =20 #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) +{ + struct pt_regs *regs =3D arch_ftrace_get_regs(fregs); + unsigned long *parent =3D (unsigned long *)®s->ra; + + prepare_ftrace_return(parent, ip, frame_pointer(regs)); +} +#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ extern void ftrace_graph_call(void); -extern void ftrace_graph_regs_call(void); int ftrace_enable_ftrace_graph_caller(void) { - int ret; - - ret =3D __ftrace_modify_call((unsigned long)&ftrace_graph_call, - (unsigned long)&prepare_ftrace_return, true, true); - if (ret) - return ret; - - return __ftrace_modify_call((unsigned long)&ftrace_graph_regs_call, + return __ftrace_modify_call((unsigned long)&ftrace_graph_call, (unsigned long)&prepare_ftrace_return, true, true); } =20 int ftrace_disable_ftrace_graph_caller(void) { - int ret; - - ret =3D __ftrace_modify_call((unsigned long)&ftrace_graph_call, - (unsigned long)&prepare_ftrace_return, false, true); - if (ret) - return ret; - - return __ftrace_modify_call((unsigned long)&ftrace_graph_regs_call, + return __ftrace_modify_call((unsigned long)&ftrace_graph_call, (unsigned long)&prepare_ftrace_return, false, true); } +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ #endif /* CONFIG_DYNAMIC_FTRACE */ #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index 125de818d1ba..f26e9f6e2fed 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -57,19 +57,52 @@ .endm =20 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS - .macro SAVE_ALL + +/** +* SAVE_ABI_REGS - save regs against the pt_regs struct +* +* @all: tell if saving all the regs +* +* If all is set, all the regs will be saved, otherwise only ABI +* related regs (a0-a7,epc,ra and optional s0) will be saved. +* +* After the stack is established, +* +* 0(sp) stores the PC of the traced function which can be accessed +* by &(fregs)->regs->epc in tracing function. Note that the real +* function entry address should be computed with -FENTRY_RA_OFFSET. +* +* 8(sp) stores the function return address (i.e. parent IP) that +* can be accessed by &(fregs)->regs->ra in tracing function. +* +* The other regs are saved at the respective localtion and accessed +* by the respective pt_regs member. +* +* Here is the layout of stack for your reference. +* +* PT_SIZE_ON_STACK -> +++++++++ +* + ..... + +* + t3-t6 + +* + s2-s11+ +* + a0-a7 + --++++-> ftrace_caller saved +* + s1 + + +* + s0 + --+ +* + t0-t2 + + +* + tp + + +* + gp + + +* + sp + + +* + ra + --+ // parent IP +* sp -> + epc + --+ // PC +* +++++++++ +**/ + .macro SAVE_ABI_REGS, all=3D0 addi sp, sp, -PT_SIZE_ON_STACK =20 REG_S t0, PT_EPC(sp) REG_S x1, PT_RA(sp) - REG_S x2, PT_SP(sp) - REG_S x3, PT_GP(sp) - REG_S x4, PT_TP(sp) - REG_S x5, PT_T0(sp) - REG_S x6, PT_T1(sp) - REG_S x7, PT_T2(sp) - REG_S x8, PT_S0(sp) - REG_S x9, PT_S1(sp) + + // always save the ABI regs + REG_S x10, PT_A0(sp) REG_S x11, PT_A1(sp) REG_S x12, PT_A2(sp) @@ -78,6 +111,18 @@ REG_S x15, PT_A5(sp) REG_S x16, PT_A6(sp) REG_S x17, PT_A7(sp) + + // save the leftover regs + + .if \all =3D=3D 1 + REG_S x2, PT_SP(sp) + REG_S x3, PT_GP(sp) + REG_S x4, PT_TP(sp) + REG_S x5, PT_T0(sp) + REG_S x6, PT_T1(sp) + REG_S x7, PT_T2(sp) + REG_S x8, PT_S0(sp) + REG_S x9, PT_S1(sp) REG_S x18, PT_S2(sp) REG_S x19, PT_S3(sp) REG_S x20, PT_S4(sp) @@ -92,18 +137,19 @@ REG_S x29, PT_T4(sp) REG_S x30, PT_T5(sp) REG_S x31, PT_T6(sp) + + // save s0 if FP_TEST defined + + .else +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST + REG_S x8, PT_S0(sp) +#endif + .endif .endm =20 - .macro RESTORE_ALL + .macro RESTORE_ABI_REGS, all=3D0 REG_L t0, PT_EPC(sp) REG_L x1, PT_RA(sp) - REG_L x2, PT_SP(sp) - REG_L x3, PT_GP(sp) - REG_L x4, PT_TP(sp) - REG_L x6, PT_T1(sp) - REG_L x7, PT_T2(sp) - REG_L x8, PT_S0(sp) - REG_L x9, PT_S1(sp) REG_L x10, PT_A0(sp) REG_L x11, PT_A1(sp) REG_L x12, PT_A2(sp) @@ -112,6 +158,15 @@ REG_L x15, PT_A5(sp) REG_L x16, PT_A6(sp) REG_L x17, PT_A7(sp) + + .if \all =3D=3D 1 + REG_L x2, PT_SP(sp) + REG_L x3, PT_GP(sp) + REG_L x4, PT_TP(sp) + REG_L x6, PT_T1(sp) + REG_L x7, PT_T2(sp) + REG_L x8, PT_S0(sp) + REG_L x9, PT_S1(sp) REG_L x18, PT_S2(sp) REG_L x19, PT_S3(sp) REG_L x20, PT_S4(sp) @@ -127,10 +182,25 @@ REG_L x30, PT_T5(sp) REG_L x31, PT_T6(sp) =20 + .else +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST + REG_L x8, PT_S0(sp) +#endif + .endif addi sp, sp, PT_SIZE_ON_STACK .endm + + .macro PREPARE_ARGS + addi a0, t0, -FENTRY_RA_OFFSET // ip + la a1, function_trace_op + REG_L a2, 0(a1) // op + mv a1, ra // parent_ip + mv a3, sp // fregs + .endm + #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ =20 +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS ENTRY(ftrace_caller) SAVE_ABI =20 @@ -159,33 +229,28 @@ ftrace_graph_call: jr t0 ENDPROC(ftrace_caller) =20 -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ ENTRY(ftrace_regs_caller) - SAVE_ALL - - addi a0, t0, -FENTRY_RA_OFFSET - la a1, function_trace_op - REG_L a2, 0(a1) - mv a1, ra - mv a3, sp + SAVE_ABI_REGS 1 + PREPARE_ARGS =20 ftrace_regs_call: .global ftrace_regs_call call ftrace_stub =20 -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - addi a0, sp, PT_RA - REG_L a1, PT_EPC(sp) - addi a1, a1, -FENTRY_RA_OFFSET -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST - mv a2, s0 -#endif -ftrace_graph_regs_call: - .global ftrace_graph_regs_call + RESTORE_ABI_REGS 1 + jr t0 +ENDPROC(ftrace_regs_caller) + +ENTRY(ftrace_caller) + SAVE_ABI_REGS 0 + PREPARE_ARGS + +ftrace_call: + .global ftrace_call call ftrace_stub -#endif =20 - RESTORE_ALL + RESTORE_ABI_REGS 0 jr t0 -ENDPROC(ftrace_regs_caller) +ENDPROC(ftrace_caller) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ --=20 2.36.1