From nobody Mon Feb 9 01:45:02 2026 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 551F8EB64D7 for ; Wed, 21 Jun 2023 16:30:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232106AbjFUQaK (ORCPT ); Wed, 21 Jun 2023 12:30:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53240 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232285AbjFUQ3y (ORCPT ); Wed, 21 Jun 2023 12:29:54 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 456341997 for ; Wed, 21 Jun 2023 09:29:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C2676615FD for ; Wed, 21 Jun 2023 16:29:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2FF9AC433C9; Wed, 21 Jun 2023 16:29:46 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.96) (envelope-from ) id 1qC0iH-001ykW-0z; Wed, 21 Jun 2023 12:29:45 -0400 Message-ID: <20230621162945.121475688@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 21 Jun 2023 12:29:27 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Andrew Morton , Catalin Marinas , Donglin Peng Subject: [for-next][PATCH 04/13] arm64: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL References: <20230621162923.953123395@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Donglin Peng 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 ARM64 platform. We introduce a new structure called fgraph_ret_regs for the ARM64 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. Link: https://lkml.kernel.org/r/c78366416ce93f704ae7000c4ee60eb4258c38f7.16= 80954589.git.pengdonglin@sangfor.com.cn Reviewed-by: Mark Rutland Tested-by: Mark Rutland Acked-by: Catalin Marinas Signed-off-by: Donglin Peng Signed-off-by: Steven Rostedt (Google) --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/ftrace.h | 22 ++++++++++++++++++++++ arch/arm64/kernel/asm-offsets.c | 13 +++++++++++++ arch/arm64/kernel/entry-ftrace.S | 27 ++++++++++++++------------- 4 files changed, 50 insertions(+), 13 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b1201d25a8a4..f90b1780ea6c 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -201,6 +201,7 @@ config ARM64 select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_TRACER select HAVE_FUNCTION_ERROR_INJECTION + select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GCC_PLUGINS select HAVE_HW_BREAKPOINT if PERF_EVENTS diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrac= e.h index b87d70b693c6..21ac1c5c71d3 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -192,4 +192,26 @@ static inline bool arch_syscall_match_sym_name(const c= har *sym, } #endif /* ifndef __ASSEMBLY__ */ =20 +#ifndef __ASSEMBLY__ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +struct fgraph_ret_regs { + /* x0 - x7 */ + unsigned long regs[8]; + + unsigned long fp; + unsigned long __unused; +}; + +static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret= _regs *ret_regs) +{ + return ret_regs->regs[0]; +} + +static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_re= t_regs *ret_regs) +{ + return ret_regs->fp; +} +#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ +#endif + #endif /* __ASM_FTRACE_H */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offset= s.c index 0996094b0d22..757d01a68ffd 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -200,6 +200,19 @@ int main(void) #endif #ifdef CONFIG_FUNCTION_TRACER DEFINE(FTRACE_OPS_FUNC, offsetof(struct ftrace_ops, func)); +#endif + BLANK(); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + DEFINE(FGRET_REGS_X0, offsetof(struct fgraph_ret_regs, regs[0])); + DEFINE(FGRET_REGS_X1, offsetof(struct fgraph_ret_regs, regs[1])); + DEFINE(FGRET_REGS_X2, offsetof(struct fgraph_ret_regs, regs[2])); + DEFINE(FGRET_REGS_X3, offsetof(struct fgraph_ret_regs, regs[3])); + DEFINE(FGRET_REGS_X4, offsetof(struct fgraph_ret_regs, regs[4])); + DEFINE(FGRET_REGS_X5, offsetof(struct fgraph_ret_regs, regs[5])); + DEFINE(FGRET_REGS_X6, offsetof(struct fgraph_ret_regs, regs[6])); + DEFINE(FGRET_REGS_X7, offsetof(struct fgraph_ret_regs, regs[7])); + DEFINE(FGRET_REGS_FP, offsetof(struct fgraph_ret_regs, fp)); + DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs)); #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS DEFINE(FTRACE_OPS_DIRECT_CALL, offsetof(struct ftrace_ops, direct_call)); #endif diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftr= ace.S index 1c38a60575aa..f0c16640ef21 100644 --- a/arch/arm64/kernel/entry-ftrace.S +++ b/arch/arm64/kernel/entry-ftrace.S @@ -330,22 +330,23 @@ SYM_FUNC_END(ftrace_stub_graph) */ SYM_CODE_START(return_to_handler) /* save return value regs */ - sub sp, sp, #64 - stp x0, x1, [sp] - stp x2, x3, [sp, #16] - stp x4, x5, [sp, #32] - stp x6, x7, [sp, #48] + sub sp, sp, #FGRET_REGS_SIZE + stp x0, x1, [sp, #FGRET_REGS_X0] + stp x2, x3, [sp, #FGRET_REGS_X2] + stp x4, x5, [sp, #FGRET_REGS_X4] + stp x6, x7, [sp, #FGRET_REGS_X6] + str x29, [sp, #FGRET_REGS_FP] // parent's fp =20 - mov x0, x29 // parent's fp - bl ftrace_return_to_handler// addr =3D ftrace_return_to_hander(fp); - mov x30, x0 // restore the original return address + mov x0, sp + bl ftrace_return_to_handler // addr =3D ftrace_return_to_hander(regs); + mov x30, x0 // restore the original return address =20 /* restore return value regs */ - ldp x0, x1, [sp] - ldp x2, x3, [sp, #16] - ldp x4, x5, [sp, #32] - ldp x6, x7, [sp, #48] - add sp, sp, #64 + ldp x0, x1, [sp, #FGRET_REGS_X0] + ldp x2, x3, [sp, #FGRET_REGS_X2] + ldp x4, x5, [sp, #FGRET_REGS_X4] + ldp x6, x7, [sp, #FGRET_REGS_X6] + add sp, sp, #FGRET_REGS_SIZE =20 ret SYM_CODE_END(return_to_handler) --=20 2.39.2