From patchwork Tue Jun 11 03:09:36 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13692808 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8212E1E488; Tue, 11 Jun 2024 03:17:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718075843; cv=none; b=bzFhPBjXkT2+OQSGdRKTUXzMmJgmnFPm776I2tAVlvuMrfzi8Pup8DiFu5USKX+geBps/pPmsc0OHkVXuxejaFeSaaNoVXjU01AZU0tgV8zTKpgytS1XRWsra0aLWhZ4LfH6IckOlLEi+HFVaS3Po4IIwCbvmtUZpTHIoMguj1w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718075843; c=relaxed/simple; bh=lUzhAUVd8BVhSUWECv6sd9TH51t8XCPlXoOV4Dg21+Q=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=tPMeBuFfhW5qKhY3U3DcCFYw6t5FSY7mL2mJajhuNGj/bTgSggpBoXM7cT7oF+0IfhxYR6y+bceP6sTFUHCq0mlkP8Fk1fRAEi/uI4uMouy5vrNR1eIuUofFl8E5i5nUZlul0XFxIKE/OsluyASmCyb1KoA4z/hfeuXTuufVy7I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C7E5C4AF1C; Tue, 11 Jun 2024 03:17:23 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from ) id 1sGs0w-00000001JhD-0WrV; Mon, 10 Jun 2024 23:17:38 -0400 Message-ID: <20240611031737.982047614@goodmis.org> User-Agent: quilt/0.68 Date: Mon, 10 Jun 2024 23:09:36 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Jonathan Corbet , Catalin Marinas , Will Deacon , Guo Ren , Huacai Chen , WANG Xuerui , Michael Ellerman , Nicholas Piggin , Christophe Leroy , "Naveen N. Rao" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" Subject: [PATCH 2/2] function_graph: Everyone uses HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, remove it References: <20240611030934.162955582@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: "Steven Rostedt (Google)" All architectures that implement function graph also implements HAVE_FUNCTION_GRAPH_RET_ADDR_PTR. Remove it, as it is no longer a differentiator. Signed-off-by: Steven Rostedt (Google) --- Documentation/trace/ftrace-design.rst | 12 --------- arch/arm64/include/asm/ftrace.h | 11 --------- arch/csky/include/asm/ftrace.h | 2 -- arch/loongarch/include/asm/ftrace.h | 1 - arch/powerpc/include/asm/ftrace.h | 2 -- arch/riscv/include/asm/ftrace.h | 1 - arch/s390/include/asm/ftrace.h | 1 - arch/x86/include/asm/ftrace.h | 2 -- include/linux/ftrace.h | 2 -- kernel/trace/fgraph.c | 35 +-------------------------- 10 files changed, 1 insertion(+), 68 deletions(-) diff --git a/Documentation/trace/ftrace-design.rst b/Documentation/trace/ftrace-design.rst index 6893399157f0..dc82d64b3a44 100644 --- a/Documentation/trace/ftrace-design.rst +++ b/Documentation/trace/ftrace-design.rst @@ -217,18 +217,6 @@ along to ftrace_push_return_trace() instead of a stub value of 0. Similarly, when you call ftrace_return_to_handler(), pass it the frame pointer. -HAVE_FUNCTION_GRAPH_RET_ADDR_PTR --------------------------------- - -An arch may pass in a pointer to the return address on the stack. This -prevents potential stack unwinding issues where the unwinder gets out of -sync with ret_stack and the wrong addresses are reported by -ftrace_graph_ret_addr(). - -Adding support for it is easy: just define the macro in asm/ftrace.h and -pass the return address pointer as the 'retp' argument to -ftrace_push_return_trace(). - HAVE_SYSCALL_TRACEPOINTS ------------------------ diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index ab158196480c..dc9cf0bd2a4c 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -12,17 +12,6 @@ #define HAVE_FUNCTION_GRAPH_FP_TEST -/* - * HAVE_FUNCTION_GRAPH_RET_ADDR_PTR means that the architecture can provide a - * "return address pointer" which can be used to uniquely identify a return - * address which has been overwritten. - * - * On arm64 we use the address of the caller's frame record, which remains the - * same for the lifetime of the instrumented function, unlike the return - * address in the LR. - */ -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR - #ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS #define ARCH_SUPPORTS_FTRACE_OPS 1 #else diff --git a/arch/csky/include/asm/ftrace.h b/arch/csky/include/asm/ftrace.h index fd215c38ef27..00f9f7647e3f 100644 --- a/arch/csky/include/asm/ftrace.h +++ b/arch/csky/include/asm/ftrace.h @@ -7,8 +7,6 @@ #define HAVE_FUNCTION_GRAPH_FP_TEST -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR - #define ARCH_SUPPORTS_FTRACE_OPS 1 #define MCOUNT_ADDR ((unsigned long)_mcount) diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index de891c2c83d4..c0a682808e07 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -28,7 +28,6 @@ struct dyn_ftrace; struct dyn_arch_ftrace { }; #define ARCH_SUPPORTS_FTRACE_OPS 1 -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR #define ftrace_init_nop ftrace_init_nop int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index 107fc5a48456..559560286e6d 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -8,8 +8,6 @@ #define MCOUNT_ADDR ((unsigned long)(_mcount)) #define MCOUNT_INSN_SIZE 4 /* sizeof mcount call */ -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR - /* Ignore unused weak functions which will have larger offsets */ #if defined(CONFIG_MPROFILE_KERNEL) || defined(CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY) #define FTRACE_MCOUNT_MAX_OFFSET 16 diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index 9eb31a7ea0aa..2cddd79ff21b 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -11,7 +11,6 @@ #if defined(CONFIG_FUNCTION_GRAPH_TRACER) && defined(CONFIG_FRAME_POINTER) #define HAVE_FUNCTION_GRAPH_FP_TEST #endif -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR #define ARCH_SUPPORTS_FTRACE_OPS 1 #ifndef __ASSEMBLY__ diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 77e479d44f1e..fbadca645af7 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -2,7 +2,6 @@ #ifndef _ASM_S390_FTRACE_H #define _ASM_S390_FTRACE_H -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR #define ARCH_SUPPORTS_FTRACE_OPS 1 #define MCOUNT_INSN_SIZE 6 diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 897cf02c20b1..0152a81d9b4a 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -20,8 +20,6 @@ #define ARCH_SUPPORTS_FTRACE_OPS 1 #endif -#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR - #ifndef __ASSEMBLY__ extern void __fentry__(void); diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 4135dc171447..845c2ab0bc1c 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -1071,9 +1071,7 @@ struct ftrace_ret_stack { #ifdef HAVE_FUNCTION_GRAPH_FP_TEST unsigned long fp; #endif -#ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR unsigned long *retp; -#endif }; /* diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 91f1eef256af..8317d1a7f43a 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -593,9 +593,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, #ifdef HAVE_FUNCTION_GRAPH_FP_TEST ret_stack->fp = frame_pointer; #endif -#ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR ret_stack->retp = retp; -#endif return offset; } @@ -887,10 +885,8 @@ ftrace_graph_get_ret_stack(struct task_struct *task, int idx) * will be assigned that location so that if called again, it will continue * where it left off. * - * @retp is a pointer to the return address on the stack. It's ignored if - * the arch doesn't have HAVE_FUNCTION_GRAPH_RET_ADDR_PTR defined. + * @retp is a pointer to the return address on the stack. */ -#ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, unsigned long ret, unsigned long *retp) { @@ -926,35 +922,6 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, return ret; } -#else /* !HAVE_FUNCTION_GRAPH_RET_ADDR_PTR */ -unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, - unsigned long ret, unsigned long *retp) -{ - struct ftrace_ret_stack *ret_stack; - unsigned long return_handler = (unsigned long)dereference_kernel_function_descriptor(return_to_handler); - int offset = task->curr_ret_stack; - int i; - - if (ret != return_handler) - return ret; - - if (!idx) - return ret; - - i = *idx; - do { - ret_stack = get_ret_stack(task, offset, &offset); - if (ret_stack && ret_stack->ret == return_handler) - continue; - i--; - } while (i >= 0 && ret_stack); - - if (ret_stack) - return ret_stack->ret; - - return ret; -} -#endif /* HAVE_FUNCTION_GRAPH_RET_ADDR_PTR */ static struct ftrace_ops graph_ops = { .func = ftrace_graph_func,