diff options
| -rw-r--r-- | arch/i386/Kconfig | 4 | ||||
| -rw-r--r-- | arch/i386/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/i386/kernel/stacktrace.c | 98 |
3 files changed, 103 insertions, 0 deletions
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig index 27d8dddbaa4..076a72c7a41 100644 --- a/arch/i386/Kconfig +++ b/arch/i386/Kconfig @@ -18,6 +18,10 @@ config GENERIC_TIME bool default y +config STACKTRACE_SUPPORT + bool + default y + config SEMAPHORE_SLEEPERS bool default y diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile index cbc1184e947..1b452a1665c 100644 --- a/arch/i386/kernel/Makefile +++ b/arch/i386/kernel/Makefile @@ -9,6 +9,7 @@ obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o \ pci-dma.o i386_ksyms.o i387.o bootflag.o \ quirks.o i8237.o topology.o alternative.o i8253.o tsc.o +obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-y += cpu/ obj-y += acpi/ obj-$(CONFIG_X86_BIOS_REBOOT) += reboot.o diff --git a/arch/i386/kernel/stacktrace.c b/arch/i386/kernel/stacktrace.c new file mode 100644 index 00000000000..e62a037ab39 --- /dev/null +++ b/arch/i386/kernel/stacktrace.c @@ -0,0 +1,98 @@ +/* + * arch/i386/kernel/stacktrace.c + * + * Stack trace management functions + * + * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> + */ +#include <linux/sched.h> +#include <linux/stacktrace.h> + +static inline int valid_stack_ptr(struct thread_info *tinfo, void *p) +{ + return p > (void *)tinfo && + p < (void *)tinfo + THREAD_SIZE - 3; +} + +/* + * Save stack-backtrace addresses into a stack_trace buffer: + */ +static inline unsigned long +save_context_stack(struct stack_trace *trace, unsigned int skip, + struct thread_info *tinfo, unsigned long *stack, + unsigned long ebp) +{ + unsigned long addr; + +#ifdef CONFIG_FRAME_POINTER + while (valid_stack_ptr(tinfo, (void *)ebp)) { + addr = *(unsigned long *)(ebp + 4); + if (!skip) + trace->entries[trace->nr_entries++] = addr; + else + skip--; + if (trace->nr_entries >= trace->max_entries) + break; + /* + * break out of recursive entries (such as + * end_of_stack_stop_unwind_function): + */ + if (ebp == *(unsigned long *)ebp) + break; + + ebp = *(unsigned long *)ebp; + } +#else + while (valid_stack_ptr(tinfo, stack)) { + addr = *stack++; + if (__kernel_text_address(addr)) { + if (!skip) + trace->entries[trace->nr_entries++] = addr; + else + skip--; + if (trace->nr_entries >= trace->max_entries) + break; + } + } +#endif + + return ebp; +} + +/* + * Save stack-backtrace addresses into a stack_trace buffer. + * If all_contexts is set, all contexts (hardirq, softirq and process) + * are saved. If not set then only the current context is saved. + */ +void save_stack_trace(struct stack_trace *trace, + struct task_struct *task, int all_contexts, + unsigned int skip) +{ + unsigned long ebp; + unsigned long *stack = &ebp; + + WARN_ON(trace->nr_entries || !trace->max_entries); + + if (!task || task == current) { + /* Grab ebp right from our regs: */ + asm ("movl %%ebp, %0" : "=r" (ebp)); + } else { + /* ebp is the last reg pushed by switch_to(): */ + ebp = *(unsigned long *) task->thread.esp; + } + + while (1) { + struct thread_info *context = (struct thread_info *) + ((unsigned long)stack & (~(THREAD_SIZE - 1))); + + ebp = save_context_stack(trace, skip, context, stack, ebp); + stack = (unsigned long *)context->previous_esp; + if (!all_contexts || !stack || + trace->nr_entries >= trace->max_entries) + break; + trace->entries[trace->nr_entries++] = ULONG_MAX; + if (trace->nr_entries >= trace->max_entries) + break; + } +} + |