From patchwork Thu Dec 8 09:12:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 13068161 X-Patchwork-Delegate: palmer@dabbelt.com 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3B940C3A5A7 for ; Thu, 8 Dec 2022 09:32:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UfQl3ISJROfin3dN4OLBhM2NQNjJP1/8ywyl4NE/UAs=; b=txN6aG+E6zv/mL RPgHG+8EsQQMpZCahJtmkEjy35e+Ug2tbom9CZnLca/6DsYBiq06leI6gTQKnJCu4w4aqicYr9Rls 14Dovh4AlgI6X3Oezk4INZ/cxFOiataGWgv1Rboo+xX6zHw+F4okDB/VsWI7JLA7a6K9ltaRBon9k H/EMH8QEK2inQg/MbVzKm/K0hYrdk/xzBvZ/rBjPgLVH0kdN7b8C9cL7+uRIRGe5Zg5vgeD//ZZey wSbBo6Ae7/AalnyzogO2BXpi8qGZYVQCiP6qbErmzIX37QxlsMlsCR5p34U2pIjhTsTlyY78mjjNV uCOK9/tLP8jxJ/PkbZgw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p3DGR-00AvnC-17; Thu, 08 Dec 2022 09:32:23 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p3Cy4-00AhTb-Ab for linux-riscv@lists.infradead.org; Thu, 08 Dec 2022 09:13:26 +0000 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 991B961E2E; Thu, 8 Dec 2022 09:13:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 45B4CC433D6; Thu, 8 Dec 2022 09:13:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670490803; bh=LvDWkebzqIcj6lyYVhxG3SUkKIDjdF9n3kVqbRNzao8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=acXozCW9PE1mJgO3ARK0tsitM5DkvFMJmxl74UkKWlOBuS9VFSudBkixn/kAeDCf1 vnPdqyBVP/Kr2G34Sp67YrT7x/p6OG1R7fJvUj6DBi4RFupJLm7Ac7ZysAvGgAsEai oCEyxrjIb3/haw2Ujtw/1CjE6/NInkKCu7T31IUilrcLCXSP00e0Qc/yS6v6pgIG0u sxhFvypWZEiMp+bl568LR4kGfUBnU9Fif3yBgg5VnLQBGgkZKZD6rSSeDR8wjj950P vBEWgAIHH2AF2KhyCUJtYcyxTM1HYbRu3d9z1pkoTSETO6bCE32qF0WiNqSWg9Dgut 0I3e9PNwY1vQw== 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 Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Guo Ren Subject: [PATCH -next V5 5/7] riscv: ftrace: Make ftrace_caller call ftrace_graph_func Date: Thu, 8 Dec 2022 04:12:42 -0500 Message-Id: <20221208091244.203407-6-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20221208091244.203407-1-guoren@kernel.org> References: <20221208091244.203407-1-guoren@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221208_011324_506102_D35C9C8F X-CRM114-Status: GOOD ( 14.79 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Song Shuai 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 separated as PREPARE_ARGS. Signed-off-by: Song Shuai Tested-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/kernel/mcount-dyn.S | 142 ++++++++++++++++++++++++--------- 1 file changed, 104 insertions(+), 38 deletions(-) diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index 64bc79816f5e..466c6ef217b1 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -57,19 +57,52 @@ .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. +* +* 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 +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 == 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 +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 - .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 +158,16 @@ 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 +183,25 @@ 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 + + .macro PREPARE_ARGS + 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 + #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS ENTRY(ftrace_caller) SAVE_ABI @@ -160,33 +230,29 @@ 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 + PREPARE_ARGS 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 + PREPARE_ARGS + +ftrace_call: + .global ftrace_call + call ftrace_stub + + RESTORE_ABI_REGS 0 + jr t0 +ENDPROC(ftrace_caller) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */