diff options
author | Steven J. Magnani <steve@digidescorp.com> | 2010-04-27 12:37:54 -0500 |
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committer | Michal Simek <monstr@monstr.eu> | 2010-08-04 10:22:35 +0200 |
commit | ce3266c047389443d5f433d605c769e878cbe46e (patch) | |
tree | e638a255d5d0f1b000a81b512dc605b92d0b8701 /arch/microblaze/kernel/stacktrace.c | |
parent | ba9c4f88d747836bf35c3eee36aa18d2e164f493 (diff) | |
download | linux-ce3266c047389443d5f433d605c769e878cbe46e.tar.bz2 |
microblaze: Add stack unwinder
Implement intelligent backtracing by searching for stack frame creation,
and emitting only return addresses. Use print_hex_dump() to display the
entire binary kernel stack.
Limitation: MMU kernels are not currently able to trace beyond a system trap
(interrupt, syscall, etc.). It is the intent of this patch to provide
infrastructure that can be extended to add this capability later.
Changes from V1:
* Removed checks in find_frame_creation() that prevented location of the frame
creation instruction in heavily optimized code
* Various formatting/commenting/file location tweaks per review comments
* Dropped Kconfig option to enable STACKTRACE as something logically separate
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Diffstat (limited to 'arch/microblaze/kernel/stacktrace.c')
-rw-r--r-- | arch/microblaze/kernel/stacktrace.c | 44 |
1 files changed, 5 insertions, 39 deletions
diff --git a/arch/microblaze/kernel/stacktrace.c b/arch/microblaze/kernel/stacktrace.c index 123692f22647..84bc6686102c 100644 --- a/arch/microblaze/kernel/stacktrace.c +++ b/arch/microblaze/kernel/stacktrace.c @@ -14,52 +14,18 @@ #include <linux/thread_info.h> #include <linux/ptrace.h> #include <linux/module.h> +#include <asm/unwind.h> -/* FIXME initial support */ void save_stack_trace(struct stack_trace *trace) { - unsigned long *sp; - unsigned long addr; - asm("addik %0, r1, 0" : "=r" (sp)); - - while (!kstack_end(sp)) { - addr = *sp++; - if (__kernel_text_address(addr)) { - if (trace->skip > 0) - trace->skip--; - else - trace->entries[trace->nr_entries++] = addr; - - if (trace->nr_entries >= trace->max_entries) - break; - } - } + /* Exclude our helper functions from the trace*/ + trace->skip += 2; + microblaze_unwind(NULL, trace); } EXPORT_SYMBOL_GPL(save_stack_trace); void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) { - unsigned int *sp; - unsigned long addr; - - struct thread_info *ti = task_thread_info(tsk); - - if (tsk == current) - asm("addik %0, r1, 0" : "=r" (sp)); - else - sp = (unsigned int *)ti->cpu_context.r1; - - while (!kstack_end(sp)) { - addr = *sp++; - if (__kernel_text_address(addr)) { - if (trace->skip > 0) - trace->skip--; - else - trace->entries[trace->nr_entries++] = addr; - - if (trace->nr_entries >= trace->max_entries) - break; - } - } + microblaze_unwind(tsk, trace); } EXPORT_SYMBOL_GPL(save_stack_trace_tsk); |