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 537C1C4332F for ; Fri, 18 Nov 2022 17:34:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242342AbiKRReQ (ORCPT ); Fri, 18 Nov 2022 12:34:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242541AbiKRRdq (ORCPT ); Fri, 18 Nov 2022 12:33:46 -0500 Received: from mail-pj1-x1031.google.com (mail-pj1-x1031.google.com [IPv6:2607:f8b0:4864:20::1031]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 023FE99EAA for ; Fri, 18 Nov 2022 09:32:36 -0800 (PST) Received: by mail-pj1-x1031.google.com with SMTP id e7-20020a17090a77c700b00216928a3917so8908824pjs.4 for ; Fri, 18 Nov 2022 09:32:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=9NBmSk7fBSAJxNI2xlbnnvVbJDd4rleDkNQ22MfWjS4=; b=F0LYXy04+BTUjesxYiznzIMp2EPv6TsAXbgRS7pQaL8OVC5YVDOU5m8FLAC/FIzrky g023O0gv5uUPYMTsf65qv4ardfNDmUcl38ECWjHwojCt7NXtJVG3KJKr1l6WR8RljrFP rtiSJ0hvZ+xve4POcmFgudRMFpS3FTy5EaS4Gp6yEvXM8t7ByKn/EOEiFaG72rgpdwtE Ia1Qz9fLb20rSXAqzcEWosodqLqAhvtnpMJWCkTJmbTsx6dmQL6By1FcxZHnAhuYj8tx Rx9JHHuYX8ZUr+6rVgwnFnQKpG7/Ap36Kcc5H9AbqX6x0fsKxCcuJeXrTC8tCsXKkK0B 4qFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=9NBmSk7fBSAJxNI2xlbnnvVbJDd4rleDkNQ22MfWjS4=; b=PQDNXGMp1BP0t+tE7bj1jE2C1Ae2rYhzcMoM1sQs1hXrC7cl6WhbuOECdCBYRFeLo5 Tce/Kalygsh+kfBJR0GIrvMyS3DYDbmqUzVJB0Weo7WRIxIqaPXZK7wPAdD8INtCnWIN MBinYn0v1jFi1hXSMUhfeKAPkGZ12b06KyQI3GkFzamItTzd+ONEwNEwO4MYvKp3299D OlrcjwUsmI2cH/IiTdp0jJUVrvcYlJfPNlSXnnb4NvGNJUUacfe0IJzLn4igbIA/pG/s qXXPDUI5FNHQ83i+y+m2YAd9Xnlsa2l424ULDp5iN0D+OD5dIx9lZLx77qrDW6zzo+2c EW5w== X-Gm-Message-State: ANoB5plNiKo20L/BY3NmNHGR3iZq3B/LqaV/FvpeH7jhsOCXRO0e+m3p kawnYrKQ1KVk8aSKduFoqSA= X-Google-Smtp-Source: AA0mqf4QhHX9xixekXRosr4UFGQ5KWFFv0b2o6M8eemOOc2cuROcW7yNBijARk3dISgqt+U20PDZ2A== X-Received: by 2002:a17:902:cf0e:b0:17c:5b01:f227 with SMTP id i14-20020a170902cf0e00b0017c5b01f227mr620277plg.3.1668792755984; Fri, 18 Nov 2022 09:32:35 -0800 (PST) Received: from localhost.localdomain ([112.2.231.196]) by smtp.gmail.com with ESMTPSA id u7-20020a656707000000b00476b6b7f339sm3037979pgf.11.2022.11.18.09.32.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Nov 2022 09:32:35 -0800 (PST) From: Song Shuai To: guoren@kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, mark.rutland@arm.com, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Song Shuai Subject: [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func Date: Sat, 19 Nov 2022 01:32:17 +0800 Message-Id: <20221118173217.888077-3-suagrfillet@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20221118173217.888077-1-suagrfillet@gmail.com> References: <20221118173217.888077-1-suagrfillet@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to make the function graph use ftrace directly, ftrace_caller should be adjusted to save the necessary regs against the pt_regs layout so it can call ftrace_graph_func reasonably. SAVE_ALL now saves all the regs according to the pt_regs struct. Here supersedes SAVE_ALL by SAVE_ABI_REGS which has an extra option to allow saving only the necessary ABI-related regs for ftrace_caller. ftrace_caller and ftrace_regs_caller save their regs with the respective option of SAVE_ABI_REGS, then call the tracing function, especially graph_ops's ftrace_graph_func. So the ftrace_graph_[regs]_call labels aren't needed anymore if FTRACE_WITH_REGS is defined. As the previous patch described, the ftrace_caller remains with its ftrace_graph_call if FTRACE_WITH_REGS isn't defined, For convenience, the original argument setup for the tracing function in ftrace_[regs]_caller is killed and appended to the tail of SAVE_ABI_REGS. Signed-off-by: Song Shuai --- arch/riscv/kernel/mcount-dyn.S | 143 ++++++++++++++++++++++++--------- 1 file changed, 105 insertions(+), 38 deletions(-) diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index 64bc79816f5e..c70f04711a2e 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -57,19 +57,55 @@ .endm #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. +* +* For convenience the argument setup for tracing function is appended here. +* Especially $sp is passed as the 4th argument of the tracing function. +* +* 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=0 addi sp, sp, -PT_SIZE_ON_STACK 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 +114,18 @@ REG_S x15, PT_A5(sp) REG_S x16, PT_A6(sp) REG_S x17, PT_A7(sp) + + // save the leftover regs + + .if \all == 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) @@ -92,19 +140,28 @@ 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 + + // setup 4 args for tracing functions + + addi a0, t0, -FENTRY_RA_OFFSET // ip + la a1, function_trace_op + REG_L a2, 0(a1) // op + REG_L a1, PT_RA(sp) // parent_ip + mv a3, sp // fregs + .endm - .macro RESTORE_ALL + .macro RESTORE_ABI_REGS, all=0 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 x5, PT_T0(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) @@ -113,6 +170,16 @@ REG_L x15, PT_A5(sp) REG_L x16, PT_A6(sp) REG_L x17, PT_A7(sp) + + .if \all == 1 + REG_L x2, PT_SP(sp) + REG_L x3, PT_GP(sp) + REG_L x4, PT_TP(sp) + REG_L x5, PT_T0(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) @@ -128,10 +195,16 @@ REG_L x30, PT_T5(sp) REG_L x31, PT_T6(sp) + .else +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST + REG_L x8, PT_S0(sp) +#endif + .endif addi sp, sp, PT_SIZE_ON_STACK .endm #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS ENTRY(ftrace_caller) SAVE_ABI @@ -160,33 +233,27 @@ ftrace_graph_call: jr t0 ENDPROC(ftrace_caller) -#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) - REG_L a1, PT_RA(sp) - mv a3, sp + SAVE_ABI_REGS 1 ftrace_regs_call: .global ftrace_regs_call call ftrace_stub -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - addi a0, sp, PT_RA - REG_L a1, PT_T0(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 - call ftrace_stub -#endif - RESTORE_ALL + RESTORE_ABI_REGS 1 jr t0 ENDPROC(ftrace_regs_caller) + +ENTRY(ftrace_caller) + SAVE_ABI_REGS 0 + +ftrace_call: + .global ftrace_call + call ftrace_stub + + RESTORE_ABI_REGS 0 + jr t0 +ENDPROC(ftrace_caller) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ -- 2.20.1