diff options
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/Makefile | 4 | ||||
| -rw-r--r-- | arch/arm/kernel/return_address.c | 71 | ||||
| -rw-r--r-- | arch/arm/kernel/stacktrace.c | 4 |
3 files changed, 76 insertions, 3 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index ff89d0b3abc5..3213c9382b17 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -8,10 +8,12 @@ ifdef CONFIG_DYNAMIC_FTRACE CFLAGS_REMOVE_ftrace.o = -pg endif +CFLAGS_REMOVE_return_address.o = -pg + # Object file lists. obj-y := compat.o elf.o entry-armv.o entry-common.o irq.o \ - process.o ptrace.o setup.o signal.o \ + process.o ptrace.o return_address.o setup.o signal.o \ sys_arm.o stacktrace.o time.o traps.o obj-$(CONFIG_ISA_DMA_API) += dma.o diff --git a/arch/arm/kernel/return_address.c b/arch/arm/kernel/return_address.c new file mode 100644 index 000000000000..df246da4ceca --- /dev/null +++ b/arch/arm/kernel/return_address.c @@ -0,0 +1,71 @@ +/* + * arch/arm/kernel/return_address.c + * + * Copyright (C) 2009 Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> + * for Pengutronix + * + * 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/module.h> + +#if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) +#include <linux/sched.h> + +#include <asm/stacktrace.h> + +struct return_address_data { + unsigned int level; + void *addr; +}; + +static int save_return_addr(struct stackframe *frame, void *d) +{ + struct return_address_data *data = d; + + if (!data->level) { + data->addr = (void *)frame->lr; + + return 1; + } else { + --data->level; + return 0; + } +} + +void *return_address(unsigned int level) +{ + struct return_address_data data; + struct stackframe frame; + register unsigned long current_sp asm ("sp"); + + data.level = level + 1; + + frame.fp = (unsigned long)__builtin_frame_address(0); + frame.sp = current_sp; + frame.lr = (unsigned long)__builtin_return_address(0); + frame.pc = (unsigned long)return_address; + + walk_stackframe(&frame, save_return_addr, &data); + + if (!data.level) + return data.addr; + else + return NULL; +} + +#else /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */ + +#if defined(CONFIG_ARM_UNWIND) +#warning "TODO: return_address should use unwind tables" +#endif + +void *return_address(unsigned int level) +{ + return NULL; +} + +#endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) / else */ + +EXPORT_SYMBOL_GPL(return_address); diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c index 9f444e5cc165..20b7411e47fd 100644 --- a/arch/arm/kernel/stacktrace.c +++ b/arch/arm/kernel/stacktrace.c @@ -21,7 +21,7 @@ * Note that with framepointer enabled, even the leaf functions have the same * prologue and epilogue, therefore we can ignore the LR value in this case. */ -int unwind_frame(struct stackframe *frame) +int notrace unwind_frame(struct stackframe *frame) { unsigned long high, low; unsigned long fp = frame->fp; @@ -43,7 +43,7 @@ int unwind_frame(struct stackframe *frame) } #endif -void walk_stackframe(struct stackframe *frame, +void notrace walk_stackframe(struct stackframe *frame, int (*fn)(struct stackframe *, void *), void *data) { while (1) { |
