From: AKASHI Takahiro <takahiro.akashi@linaro.org> To: rostedt@goodmis.org, fweisbec@gmail.com, mingo@redhat.com, catalin.marinas@arm.com, will.deacon@arm.com, tim.bird@sonymobile.com Cc: gkulkarni@caviumnetworks.com, dsaxena@linaro.org, arndb@arndb.de, linux-arm-kernel@lists.infradead.org, linaro-kernel@lists.linaro.org, linux-kernel@vger.kernel.org, AKASHI Takahiro <takahiro.akashi@linaro.org> Subject: [PATCH v6 4/7] arm64: Add ftrace support Date: Thu, 13 Mar 2014 19:13:47 +0900 [thread overview] Message-ID: <1394705630-12384-5-git-send-email-takahiro.akashi@linaro.org> (raw) In-Reply-To: <1394705630-12384-1-git-send-email-takahiro.akashi@linaro.org> This patch implements arm64 specific part to support function tracers, such as function (CONFIG_FUNCTION_TRACER), function_graph (CONFIG_FUNCTION_GRAPH_TRACER) and function profiler (CONFIG_FUNCTION_PROFILER). With 'function' tracer, all the functions in the kernel are traced with timestamps in ${sysfs}/tracing/trace. If function_graph tracer is specified, call graph is generated. The kernel must be compiled with -pg option so that _mcount() is inserted at the beginning of functions. This function is called on every function's entry as long as tracing is enabled. In addition, function_graph tracer also needs to be able to probe function's exit. ftrace_graph_caller() & return_to_handler do this by faking link register's value to intercept function's return path. More details on architecture specific requirements are described in Documentation/trace/ftrace-design.txt. Reviewed-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> --- arch/arm64/Kconfig | 2 + arch/arm64/include/asm/ftrace.h | 23 +++++ arch/arm64/kernel/Makefile | 4 + arch/arm64/kernel/arm64ksyms.c | 4 + arch/arm64/kernel/entry-ftrace.S | 175 ++++++++++++++++++++++++++++++++++++++ arch/arm64/kernel/ftrace.c | 64 ++++++++++++++ 6 files changed, 272 insertions(+) create mode 100644 arch/arm64/include/asm/ftrace.h create mode 100644 arch/arm64/kernel/entry-ftrace.S create mode 100644 arch/arm64/kernel/ftrace.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 340e344..6b3fef6 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -35,6 +35,8 @@ config ARM64 select HAVE_DMA_CONTIGUOUS select HAVE_EFFICIENT_UNALIGNED_ACCESS select HAVE_FTRACE_MCOUNT_RECORD + select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GENERIC_DMA_COHERENT select HAVE_HW_BREAKPOINT if PERF_EVENTS select HAVE_MEMBLOCK diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h new file mode 100644 index 0000000..58ea595 --- /dev/null +++ b/arch/arm64/include/asm/ftrace.h @@ -0,0 +1,23 @@ +/* + * arch/arm64/include/asm/ftrace.h + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef __ASM_FTRACE_H +#define __ASM_FTRACE_H + +#include <asm/insn.h> + +#define MCOUNT_ADDR ((unsigned long)_mcount) +#define MCOUNT_INSN_SIZE AARCH64_INSN_SIZE + +#ifndef __ASSEMBLY__ +extern void _mcount(unsigned long); +#endif /* __ASSEMBLY__ */ + +#endif /* __ASM_FTRACE_H */ diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 2d4554b..ac67fd0 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -5,6 +5,9 @@ CPPFLAGS_vmlinux.lds := -DTEXT_OFFSET=$(TEXT_OFFSET) AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) +CFLAGS_REMOVE_ftrace.o = -pg +CFLAGS_REMOVE_insn.o = -pg + # Object file lists. arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \ entry-fpsimd.o process.o ptrace.o setup.o signal.o \ @@ -13,6 +16,7 @@ arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \ arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \ sys_compat.o +arm64-obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o entry-ftrace.o arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c index 338b568..7f0512f 100644 --- a/arch/arm64/kernel/arm64ksyms.c +++ b/arch/arm64/kernel/arm64ksyms.c @@ -56,3 +56,7 @@ EXPORT_SYMBOL(clear_bit); EXPORT_SYMBOL(test_and_clear_bit); EXPORT_SYMBOL(change_bit); EXPORT_SYMBOL(test_and_change_bit); + +#ifdef CONFIG_FUNCTION_TRACER +EXPORT_SYMBOL(_mcount); +#endif diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S new file mode 100644 index 0000000..0ac31c8 --- /dev/null +++ b/arch/arm64/kernel/entry-ftrace.S @@ -0,0 +1,175 @@ +/* + * arch/arm64/kernel/entry-ftrace.S + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/linkage.h> +#include <asm/ftrace.h> +#include <asm/insn.h> + +/* + * Gcc with -pg will put the following code in the beginning of each function: + * mov x0, x30 + * bl _mcount + * [function's body ...] + * "bl _mcount" may be replaced to "bl ftrace_caller" or NOP if dynamic + * ftrace is enabled. + * + * Please note that x0 as an argument will not be used here because we can + * get lr(x30) of instrumented function at any time by winding up call stack + * as long as the kernel is compiled without -fomit-frame-pointer. + * (or CONFIG_FRAME_POINTER, this is forced on arm64) + * + * stack layout after mcount_enter in _mcount(): + * + * current sp/fp => 0:+-----+ + * in _mcount() | x29 | -> instrumented function's fp + * +-----+ + * | x30 | -> _mcount()'s lr (= instrumented function's pc) + * old sp => +16:+-----+ + * when instrumented | | + * function calls | ... | + * _mcount() | | + * | | + * instrumented => +xx:+-----+ + * function's fp | x29 | -> parent's fp + * +-----+ + * | x30 | -> instrumented function's lr (= parent's pc) + * +-----+ + * | ... | + */ + + .macro mcount_enter + stp x29, x30, [sp, #-16]! + mov x29, sp + .endm + + .macro mcount_exit + ldp x29, x30, [sp], #16 + ret + .endm + + .macro mcount_adjust_addr rd, rn + sub \rd, \rn, #AARCH64_INSN_SIZE + .endm + + /* for instrumented function's parent */ + .macro mcount_get_parent_fp reg + ldr \reg, [x29] + ldr \reg, [\reg] + .endm + + /* for instrumented function */ + .macro mcount_get_pc0 reg + mcount_adjust_addr \reg, x30 + .endm + + .macro mcount_get_pc reg + ldr \reg, [x29, #8] + mcount_adjust_addr \reg, \reg + .endm + + .macro mcount_get_lr reg + ldr \reg, [x29] + ldr \reg, [\reg, #8] + mcount_adjust_addr \reg, \reg + .endm + + .macro mcount_get_lr_addr reg + ldr \reg, [x29] + add \reg, \reg, #8 + .endm + +/* + * void _mcount(unsigned long return_address) + * @return_address: return address to instrumented function + * + * This function makes calls, if enabled, to: + * - tracer function to probe instrumented function's entry, + * - ftrace_graph_caller to set up an exit hook + */ +ENTRY(_mcount) +#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST + ldr x0, =ftrace_trace_stop + ldr x0, [x0] // if ftrace_trace_stop + ret // return; +#endif + mcount_enter + + ldr x0, =ftrace_trace_function + ldr x2, [x0] + adr x0, ftrace_stub + cmp x0, x2 // if (ftrace_trace_function + b.eq skip_ftrace_call // != ftrace_stub) { + + mcount_get_pc x0 // function's pc + mcount_get_lr x1 // function's lr (= parent's pc) + blr x2 // (*ftrace_trace_function)(pc, lr); + +#ifndef CONFIG_FUNCTION_GRAPH_TRACER +skip_ftrace_call: // return; + mcount_exit // } +#else + mcount_exit // return; + // } +skip_ftrace_call: + ldr x1, =ftrace_graph_return + ldr x2, [x1] // if ((ftrace_graph_return + cmp x0, x2 // != ftrace_stub) + b.ne ftrace_graph_caller + + ldr x1, =ftrace_graph_entry // || (ftrace_graph_entry + ldr x2, [x1] // != ftrace_graph_entry_stub)) + ldr x0, =ftrace_graph_entry_stub + cmp x0, x2 + b.ne ftrace_graph_caller // ftrace_graph_caller(); + + mcount_exit +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +ENDPROC(_mcount) + +ENTRY(ftrace_stub) + ret +ENDPROC(ftrace_stub) + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +/* + * void ftrace_graph_caller(void) + * + * Called from _mcount() or ftrace_caller() when function_graph tracer is + * selected. + * This function w/ prepare_ftrace_return() fakes link register's value on + * the call stack in order to intercept instrumented function's return path + * and run return_to_handler() later on its exit. + */ +ENTRY(ftrace_graph_caller) + mcount_get_lr_addr x0 // pointer to function's saved lr + mcount_get_pc x1 // function's pc + mcount_get_parent_fp x2 // parent's fp + bl prepare_ftrace_return // prepare_ftrace_return(&lr, pc, fp) + + mcount_exit +ENDPROC(ftrace_graph_caller) + +/* + * void return_to_handler(void) + * + * Run ftrace_return_to_handler() before going back to parent. + * @fp is checked against the value passed by ftrace_graph_caller() + * only when CONFIG_FUNCTION_GRAPH_FP_TEST is enabled. + */ + .global return_to_handler +return_to_handler: + str x0, [sp, #-16]! + mov x0, x29 // parent's fp + bl ftrace_return_to_handler// addr = ftrace_return_to_hander(fp); + mov x30, x0 // restore the original return address + ldr x0, [sp], #16 + ret +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c new file mode 100644 index 0000000..a559ab8 --- /dev/null +++ b/arch/arm64/kernel/ftrace.c @@ -0,0 +1,64 @@ +/* + * arch/arm64/kernel/ftrace.c + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/ftrace.h> +#include <linux/swab.h> +#include <linux/uaccess.h> + +#include <asm/cacheflush.h> +#include <asm/ftrace.h> +#include <asm/insn.h> + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +/* + * function_graph tracer expects ftrace_return_to_handler() to be called + * on the way back to parent. For this purpose, this function is called + * in _mcount() or ftrace_caller() to replace return address (*parent) on + * the call stack to return_to_handler. + * + * Note that @frame_pointer is used only for sanity check later. + */ +void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, + unsigned long frame_pointer) +{ + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long old; + struct ftrace_graph_ent trace; + int err; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + /* + * Note: + * No protection against faulting at *parent, which may be seen + * on other archs. It's unlikely on AArch64. + */ + old = *parent; + *parent = return_hooker; + + trace.func = self_addr; + trace.depth = current->curr_ret_stack + 1; + + /* Only trace if the calling function expects to */ + if (!ftrace_graph_entry(&trace)) { + *parent = old; + return; + } + + err = ftrace_push_return_trace(old, self_addr, &trace.depth, + frame_pointer); + if (err == -EBUSY) { + *parent = old; + return; + } +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -- 1.7.9.5
WARNING: multiple messages have this Message-ID (diff)
From: takahiro.akashi@linaro.org (AKASHI Takahiro) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v6 4/7] arm64: Add ftrace support Date: Thu, 13 Mar 2014 19:13:47 +0900 [thread overview] Message-ID: <1394705630-12384-5-git-send-email-takahiro.akashi@linaro.org> (raw) In-Reply-To: <1394705630-12384-1-git-send-email-takahiro.akashi@linaro.org> This patch implements arm64 specific part to support function tracers, such as function (CONFIG_FUNCTION_TRACER), function_graph (CONFIG_FUNCTION_GRAPH_TRACER) and function profiler (CONFIG_FUNCTION_PROFILER). With 'function' tracer, all the functions in the kernel are traced with timestamps in ${sysfs}/tracing/trace. If function_graph tracer is specified, call graph is generated. The kernel must be compiled with -pg option so that _mcount() is inserted at the beginning of functions. This function is called on every function's entry as long as tracing is enabled. In addition, function_graph tracer also needs to be able to probe function's exit. ftrace_graph_caller() & return_to_handler do this by faking link register's value to intercept function's return path. More details on architecture specific requirements are described in Documentation/trace/ftrace-design.txt. Reviewed-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> --- arch/arm64/Kconfig | 2 + arch/arm64/include/asm/ftrace.h | 23 +++++ arch/arm64/kernel/Makefile | 4 + arch/arm64/kernel/arm64ksyms.c | 4 + arch/arm64/kernel/entry-ftrace.S | 175 ++++++++++++++++++++++++++++++++++++++ arch/arm64/kernel/ftrace.c | 64 ++++++++++++++ 6 files changed, 272 insertions(+) create mode 100644 arch/arm64/include/asm/ftrace.h create mode 100644 arch/arm64/kernel/entry-ftrace.S create mode 100644 arch/arm64/kernel/ftrace.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 340e344..6b3fef6 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -35,6 +35,8 @@ config ARM64 select HAVE_DMA_CONTIGUOUS select HAVE_EFFICIENT_UNALIGNED_ACCESS select HAVE_FTRACE_MCOUNT_RECORD + select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GENERIC_DMA_COHERENT select HAVE_HW_BREAKPOINT if PERF_EVENTS select HAVE_MEMBLOCK diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h new file mode 100644 index 0000000..58ea595 --- /dev/null +++ b/arch/arm64/include/asm/ftrace.h @@ -0,0 +1,23 @@ +/* + * arch/arm64/include/asm/ftrace.h + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef __ASM_FTRACE_H +#define __ASM_FTRACE_H + +#include <asm/insn.h> + +#define MCOUNT_ADDR ((unsigned long)_mcount) +#define MCOUNT_INSN_SIZE AARCH64_INSN_SIZE + +#ifndef __ASSEMBLY__ +extern void _mcount(unsigned long); +#endif /* __ASSEMBLY__ */ + +#endif /* __ASM_FTRACE_H */ diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 2d4554b..ac67fd0 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -5,6 +5,9 @@ CPPFLAGS_vmlinux.lds := -DTEXT_OFFSET=$(TEXT_OFFSET) AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) +CFLAGS_REMOVE_ftrace.o = -pg +CFLAGS_REMOVE_insn.o = -pg + # Object file lists. arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \ entry-fpsimd.o process.o ptrace.o setup.o signal.o \ @@ -13,6 +16,7 @@ arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \ arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \ sys_compat.o +arm64-obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o entry-ftrace.o arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c index 338b568..7f0512f 100644 --- a/arch/arm64/kernel/arm64ksyms.c +++ b/arch/arm64/kernel/arm64ksyms.c @@ -56,3 +56,7 @@ EXPORT_SYMBOL(clear_bit); EXPORT_SYMBOL(test_and_clear_bit); EXPORT_SYMBOL(change_bit); EXPORT_SYMBOL(test_and_change_bit); + +#ifdef CONFIG_FUNCTION_TRACER +EXPORT_SYMBOL(_mcount); +#endif diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S new file mode 100644 index 0000000..0ac31c8 --- /dev/null +++ b/arch/arm64/kernel/entry-ftrace.S @@ -0,0 +1,175 @@ +/* + * arch/arm64/kernel/entry-ftrace.S + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/linkage.h> +#include <asm/ftrace.h> +#include <asm/insn.h> + +/* + * Gcc with -pg will put the following code in the beginning of each function: + * mov x0, x30 + * bl _mcount + * [function's body ...] + * "bl _mcount" may be replaced to "bl ftrace_caller" or NOP if dynamic + * ftrace is enabled. + * + * Please note that x0 as an argument will not be used here because we can + * get lr(x30) of instrumented function at any time by winding up call stack + * as long as the kernel is compiled without -fomit-frame-pointer. + * (or CONFIG_FRAME_POINTER, this is forced on arm64) + * + * stack layout after mcount_enter in _mcount(): + * + * current sp/fp => 0:+-----+ + * in _mcount() | x29 | -> instrumented function's fp + * +-----+ + * | x30 | -> _mcount()'s lr (= instrumented function's pc) + * old sp => +16:+-----+ + * when instrumented | | + * function calls | ... | + * _mcount() | | + * | | + * instrumented => +xx:+-----+ + * function's fp | x29 | -> parent's fp + * +-----+ + * | x30 | -> instrumented function's lr (= parent's pc) + * +-----+ + * | ... | + */ + + .macro mcount_enter + stp x29, x30, [sp, #-16]! + mov x29, sp + .endm + + .macro mcount_exit + ldp x29, x30, [sp], #16 + ret + .endm + + .macro mcount_adjust_addr rd, rn + sub \rd, \rn, #AARCH64_INSN_SIZE + .endm + + /* for instrumented function's parent */ + .macro mcount_get_parent_fp reg + ldr \reg, [x29] + ldr \reg, [\reg] + .endm + + /* for instrumented function */ + .macro mcount_get_pc0 reg + mcount_adjust_addr \reg, x30 + .endm + + .macro mcount_get_pc reg + ldr \reg, [x29, #8] + mcount_adjust_addr \reg, \reg + .endm + + .macro mcount_get_lr reg + ldr \reg, [x29] + ldr \reg, [\reg, #8] + mcount_adjust_addr \reg, \reg + .endm + + .macro mcount_get_lr_addr reg + ldr \reg, [x29] + add \reg, \reg, #8 + .endm + +/* + * void _mcount(unsigned long return_address) + * @return_address: return address to instrumented function + * + * This function makes calls, if enabled, to: + * - tracer function to probe instrumented function's entry, + * - ftrace_graph_caller to set up an exit hook + */ +ENTRY(_mcount) +#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST + ldr x0, =ftrace_trace_stop + ldr x0, [x0] // if ftrace_trace_stop + ret // return; +#endif + mcount_enter + + ldr x0, =ftrace_trace_function + ldr x2, [x0] + adr x0, ftrace_stub + cmp x0, x2 // if (ftrace_trace_function + b.eq skip_ftrace_call // != ftrace_stub) { + + mcount_get_pc x0 // function's pc + mcount_get_lr x1 // function's lr (= parent's pc) + blr x2 // (*ftrace_trace_function)(pc, lr); + +#ifndef CONFIG_FUNCTION_GRAPH_TRACER +skip_ftrace_call: // return; + mcount_exit // } +#else + mcount_exit // return; + // } +skip_ftrace_call: + ldr x1, =ftrace_graph_return + ldr x2, [x1] // if ((ftrace_graph_return + cmp x0, x2 // != ftrace_stub) + b.ne ftrace_graph_caller + + ldr x1, =ftrace_graph_entry // || (ftrace_graph_entry + ldr x2, [x1] // != ftrace_graph_entry_stub)) + ldr x0, =ftrace_graph_entry_stub + cmp x0, x2 + b.ne ftrace_graph_caller // ftrace_graph_caller(); + + mcount_exit +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +ENDPROC(_mcount) + +ENTRY(ftrace_stub) + ret +ENDPROC(ftrace_stub) + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +/* + * void ftrace_graph_caller(void) + * + * Called from _mcount() or ftrace_caller() when function_graph tracer is + * selected. + * This function w/ prepare_ftrace_return() fakes link register's value on + * the call stack in order to intercept instrumented function's return path + * and run return_to_handler() later on its exit. + */ +ENTRY(ftrace_graph_caller) + mcount_get_lr_addr x0 // pointer to function's saved lr + mcount_get_pc x1 // function's pc + mcount_get_parent_fp x2 // parent's fp + bl prepare_ftrace_return // prepare_ftrace_return(&lr, pc, fp) + + mcount_exit +ENDPROC(ftrace_graph_caller) + +/* + * void return_to_handler(void) + * + * Run ftrace_return_to_handler() before going back to parent. + * @fp is checked against the value passed by ftrace_graph_caller() + * only when CONFIG_FUNCTION_GRAPH_FP_TEST is enabled. + */ + .global return_to_handler +return_to_handler: + str x0, [sp, #-16]! + mov x0, x29 // parent's fp + bl ftrace_return_to_handler// addr = ftrace_return_to_hander(fp); + mov x30, x0 // restore the original return address + ldr x0, [sp], #16 + ret +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c new file mode 100644 index 0000000..a559ab8 --- /dev/null +++ b/arch/arm64/kernel/ftrace.c @@ -0,0 +1,64 @@ +/* + * arch/arm64/kernel/ftrace.c + * + * Copyright (C) 2013 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/ftrace.h> +#include <linux/swab.h> +#include <linux/uaccess.h> + +#include <asm/cacheflush.h> +#include <asm/ftrace.h> +#include <asm/insn.h> + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +/* + * function_graph tracer expects ftrace_return_to_handler() to be called + * on the way back to parent. For this purpose, this function is called + * in _mcount() or ftrace_caller() to replace return address (*parent) on + * the call stack to return_to_handler. + * + * Note that @frame_pointer is used only for sanity check later. + */ +void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, + unsigned long frame_pointer) +{ + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long old; + struct ftrace_graph_ent trace; + int err; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + /* + * Note: + * No protection against faulting at *parent, which may be seen + * on other archs. It's unlikely on AArch64. + */ + old = *parent; + *parent = return_hooker; + + trace.func = self_addr; + trace.depth = current->curr_ret_stack + 1; + + /* Only trace if the calling function expects to */ + if (!ftrace_graph_entry(&trace)) { + *parent = old; + return; + } + + err = ftrace_push_return_trace(old, self_addr, &trace.depth, + frame_pointer); + if (err == -EBUSY) { + *parent = old; + return; + } +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -- 1.7.9.5
next prev parent reply other threads:[~2014-03-13 10:14 UTC|newest] Thread overview: 235+ messages / expand[flat|nested] mbox.gz Atom feed top 2013-10-24 7:08 [PATCH v2 0/6] arm64: Add ftrace support AKASHI Takahiro 2013-10-24 7:08 ` [PATCH v2 1/6] " AKASHI Takahiro 2013-10-24 7:08 ` [PATCH v2 2/6] arm64: ftrace: Add dynamic " AKASHI Takahiro 2013-10-24 7:08 ` [PATCH v2 3/6] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2013-10-24 7:08 ` [PATCH v2 4/6] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2013-10-24 7:08 ` [PATCH v2 5/6] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2013-10-24 7:08 ` [PATCH v2 6/6] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 0/6] arm64: Add ftrace support AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 1/6] " AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-10 15:03 ` Arnd Bergmann 2014-02-10 15:03 ` Arnd Bergmann 2014-02-10 15:19 ` Steven Rostedt 2014-02-10 15:19 ` Steven Rostedt [not found] ` <CAB5YjtCr2KL_q1FF8kO_VKe+feg7f9qFRKtwf3xj2h0ENwuB5g@mail.gmail.com> 2014-02-12 11:03 ` Arnd Bergmann 2014-02-12 11:03 ` Arnd Bergmann 2014-02-17 18:12 ` Will Deacon 2014-02-17 18:12 ` Will Deacon 2014-02-19 10:46 ` AKASHI Takahiro 2014-02-19 10:46 ` AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 2/6] arm64: ftrace: Add dynamic " AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 3/6] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 4/6] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 5/6] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-17 19:29 ` Will Deacon 2014-02-17 19:29 ` Will Deacon 2014-02-19 10:48 ` AKASHI Takahiro 2014-02-19 10:48 ` AKASHI Takahiro 2014-02-07 10:18 ` [PATCH v3 6/6] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-02-07 10:18 ` AKASHI Takahiro 2014-02-10 14:21 ` [PATCH v3 0/6] arm64: Add ftrace support Kulkarni, Ganapatrao 2014-02-10 14:21 ` Kulkarni, Ganapatrao 2014-02-25 9:23 ` [PATCH v4 0/7] " AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 1/7] " AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 15:38 ` Kulkarni, Ganapatrao 2014-02-25 15:38 ` Kulkarni, Ganapatrao 2014-02-28 5:06 ` AKASHI Takahiro 2014-02-28 5:06 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 2/7] arm64: ftrace: Add dynamic " AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 3/7] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 4/7] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 5/7] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 6/7] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-25 9:23 ` [PATCH v4 7/7] arm64: add __ASSEMBLY__ in asm/insn.h AKASHI Takahiro 2014-02-25 9:23 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 0/7] arm64: Add ftrace support AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 1/7] " AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 2/7] arm64: ftrace: Add dynamic " AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 3/7] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 4/7] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 5/7] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 6/7] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-02-28 5:18 ` [PATCH v5 7/7] arm64: add __ASSEMBLY__ in asm/insn.h AKASHI Takahiro 2014-02-28 5:18 ` AKASHI Takahiro 2014-03-11 14:35 ` [PATCH v5 0/7] arm64: Add ftrace support Will Deacon 2014-03-11 14:35 ` Will Deacon 2014-03-12 1:47 ` AKASHI Takahiro 2014-03-12 1:47 ` AKASHI Takahiro 2014-03-12 1:58 ` Steven Rostedt 2014-03-12 1:58 ` Steven Rostedt 2014-03-12 2:02 ` Steven Rostedt 2014-03-12 2:02 ` Steven Rostedt 2014-03-13 10:13 ` [PATCH v6 " AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 10:13 ` [PATCH v6 1/7] arm64: add __ASSEMBLY__ in asm/insn.h AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 12:19 ` Will Deacon 2014-03-13 12:19 ` Will Deacon 2014-03-13 10:13 ` [PATCH v6 2/7] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 12:19 ` Will Deacon 2014-03-13 12:19 ` Will Deacon 2014-03-13 10:13 ` [PATCH v6 3/7] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 12:38 ` Will Deacon 2014-03-13 12:38 ` Will Deacon 2014-03-13 14:57 ` AKASHI Takahiro 2014-03-13 14:57 ` AKASHI Takahiro 2014-03-13 16:05 ` Will Deacon 2014-03-13 16:05 ` Will Deacon 2014-03-13 10:13 ` AKASHI Takahiro [this message] 2014-03-13 10:13 ` [PATCH v6 4/7] arm64: Add ftrace support AKASHI Takahiro 2014-03-13 17:08 ` Will Deacon 2014-03-13 17:08 ` Will Deacon 2014-03-13 18:27 ` Steven Rostedt 2014-03-13 18:27 ` Steven Rostedt 2014-03-13 18:37 ` Will Deacon 2014-03-13 18:37 ` Will Deacon 2014-03-13 18:49 ` Steven Rostedt 2014-03-13 18:49 ` Steven Rostedt 2014-03-14 4:45 ` AKASHI Takahiro 2014-03-14 4:45 ` AKASHI Takahiro 2014-03-14 10:07 ` Will Deacon 2014-03-14 10:07 ` Will Deacon 2014-03-14 16:13 ` AKASHI Takahiro 2014-03-14 16:13 ` AKASHI Takahiro 2014-03-13 10:13 ` [PATCH v6 5/7] arm64: ftrace: Add dynamic " AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 18:10 ` Will Deacon 2014-03-13 18:10 ` Will Deacon 2014-03-13 18:33 ` Steven Rostedt 2014-03-13 18:33 ` Steven Rostedt 2014-03-14 5:28 ` AKASHI Takahiro 2014-03-14 5:28 ` AKASHI Takahiro 2014-03-14 5:26 ` AKASHI Takahiro 2014-03-14 5:26 ` AKASHI Takahiro 2014-03-13 10:13 ` [PATCH v6 6/7] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 15:54 ` Will Deacon 2014-03-13 15:54 ` Will Deacon 2014-03-13 18:07 ` Steven Rostedt 2014-03-13 18:07 ` Steven Rostedt 2014-03-14 4:55 ` AKASHI Takahiro 2014-03-14 4:55 ` AKASHI Takahiro 2014-03-14 3:00 ` AKASHI Takahiro 2014-03-14 3:00 ` AKASHI Takahiro 2014-03-14 10:09 ` Will Deacon 2014-03-14 10:09 ` Will Deacon 2014-03-14 16:15 ` AKASHI Takahiro 2014-03-14 16:15 ` AKASHI Takahiro 2014-03-13 10:13 ` [PATCH v6 7/7] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2014-03-13 10:13 ` AKASHI Takahiro 2014-03-13 16:25 ` Will Deacon 2014-03-13 16:25 ` Will Deacon 2014-03-14 3:50 ` AKASHI Takahiro 2014-03-14 3:50 ` AKASHI Takahiro 2014-03-15 5:40 ` [PATCH v7 0/7] arm64: Add ftrace support AKASHI Takahiro 2014-03-15 5:40 ` AKASHI Takahiro 2014-03-15 5:40 ` [PATCH v7 1/7] arm64: add __ASSEMBLY__ in asm/insn.h AKASHI Takahiro 2014-03-15 5:40 ` AKASHI Takahiro 2014-03-15 5:40 ` [PATCH v7 2/7] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-03-15 5:40 ` AKASHI Takahiro 2014-03-15 5:40 ` [PATCH v7 3/7] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2014-03-15 5:40 ` AKASHI Takahiro 2014-04-16 13:31 ` Will Deacon 2014-04-16 13:31 ` Will Deacon 2014-04-30 9:54 ` [PATCH v8 0/8] arm64: Add ftrace support AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-04-30 9:54 ` [PATCH v8 1/8] ftrace: make CALLER_ADDRx macros more generic AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-05-02 18:13 ` Will Deacon 2014-05-02 18:13 ` Will Deacon 2014-05-02 19:02 ` Steven Rostedt 2014-05-02 19:02 ` Steven Rostedt 2014-05-02 19:03 ` Steven Rostedt 2014-05-02 19:03 ` Steven Rostedt 2014-05-02 19:19 ` Steven Rostedt 2014-05-02 19:19 ` Steven Rostedt 2014-05-12 15:58 ` Will Deacon 2014-05-12 15:58 ` Will Deacon 2014-05-12 16:05 ` Steven Rostedt 2014-05-12 16:05 ` Steven Rostedt 2014-05-12 16:12 ` Will Deacon 2014-05-12 16:12 ` Will Deacon 2014-05-12 17:23 ` Steven Rostedt 2014-05-12 17:23 ` Steven Rostedt 2014-05-20 11:29 ` AKASHI Takahiro 2014-05-20 11:29 ` AKASHI Takahiro 2014-05-20 11:31 ` [PATCH v8_1] " AKASHI Takahiro 2014-05-20 11:31 ` AKASHI Takahiro 2014-06-11 12:34 ` [PATCH v8 1/8] " Geert Uytterhoeven 2014-06-11 12:34 ` Geert Uytterhoeven 2014-06-11 12:34 ` Geert Uytterhoeven 2014-06-11 13:23 ` [PATCH] arm/ftrace: Fix function_return_addr() to function_return_address() Steven Rostedt 2014-06-11 13:23 ` Steven Rostedt 2014-06-11 13:23 ` Steven Rostedt 2014-06-11 13:38 ` Geert Uytterhoeven 2014-06-11 13:38 ` Geert Uytterhoeven 2014-06-11 13:38 ` Geert Uytterhoeven 2014-06-11 13:44 ` Steven Rostedt 2014-06-11 13:44 ` Steven Rostedt 2014-06-11 13:44 ` Steven Rostedt 2014-04-30 9:54 ` [PATCH v8 2/8] arm64: add __ASSEMBLY__ in asm/insn.h AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-04-30 9:54 ` [PATCH v8 3/8] arm64: Add 'notrace' attribute to unwind_frame() for ftrace AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-04-30 9:54 ` [PATCH v8 4/8] ftrace: Add arm64 support to recordmcount AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-04-30 9:54 ` [PATCH v8 5/8] arm64: Add ftrace support AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-05-28 20:19 ` Mark Brown 2014-05-28 20:19 ` Mark Brown 2014-05-29 8:07 ` Will Deacon 2014-05-29 8:07 ` Will Deacon 2014-05-29 9:47 ` Mark Brown 2014-05-29 9:47 ` Mark Brown 2014-04-30 9:54 ` [PATCH v8 6/8] arm64: ftrace: Add dynamic " AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-04-30 9:54 ` [PATCH v8 7/8] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-04-30 9:54 ` [PATCH v8 8/8] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2014-04-30 9:54 ` AKASHI Takahiro 2014-03-15 5:45 ` [PATCH v7 4/7] arm64: Add ftrace support AKASHI Takahiro 2014-03-15 5:45 ` AKASHI Takahiro 2014-04-16 13:45 ` Will Deacon 2014-04-16 13:45 ` Will Deacon 2014-03-15 5:45 ` [PATCH v7 5/7] arm64: ftrace: Add dynamic " AKASHI Takahiro 2014-03-15 5:45 ` AKASHI Takahiro 2014-04-16 13:48 ` Will Deacon 2014-04-16 13:48 ` Will Deacon 2014-03-15 5:45 ` [PATCH v7 6/7] arm64: ftrace: Add CALLER_ADDRx macros AKASHI Takahiro 2014-03-15 5:45 ` AKASHI Takahiro 2014-04-16 13:52 ` Will Deacon 2014-04-16 13:52 ` Will Deacon 2014-04-28 10:41 ` AKASHI Takahiro 2014-04-28 10:41 ` AKASHI Takahiro 2014-05-27 13:10 ` [for-next][PATCH] ftrace: Make CALLER_ADDRx macros more generic Steven Rostedt 2014-05-27 13:10 ` Steven Rostedt 2014-05-27 18:49 ` Will Deacon 2014-05-27 18:49 ` Will Deacon 2014-05-29 5:27 ` AKASHI Takahiro 2014-05-29 5:27 ` AKASHI Takahiro 2014-05-29 8:10 ` Will Deacon 2014-05-29 8:10 ` Will Deacon 2014-03-15 5:45 ` [PATCH v7 7/7] arm64: ftrace: Add system call tracepoint AKASHI Takahiro 2014-03-15 5:45 ` AKASHI Takahiro
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1394705630-12384-5-git-send-email-takahiro.akashi@linaro.org \ --to=takahiro.akashi@linaro.org \ --cc=arndb@arndb.de \ --cc=catalin.marinas@arm.com \ --cc=dsaxena@linaro.org \ --cc=fweisbec@gmail.com \ --cc=gkulkarni@caviumnetworks.com \ --cc=linaro-kernel@lists.linaro.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=mingo@redhat.com \ --cc=rostedt@goodmis.org \ --cc=tim.bird@sonymobile.com \ --cc=will.deacon@arm.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.