diff options
| author | Atsushi Nemoto <anemo@mba.ocn.ne.jp> | 2006-07-29 23:27:20 +0900 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2006-09-27 13:37:06 +0100 |
| commit | f66686f70a2a61e53ee8c2284f75ca342e4c0dc8 (patch) | |
| tree | 881e98d7255770314dde60109a316cf9f84522b2 /arch/mips/kernel/process.c | |
| parent | 79495d876c2074af5552a0c4b7aea600c2320e83 (diff) | |
[MIPS] dump_stack() based on prologue code analysis
Instead of dump all possible address in the stack, unwind the stack frame
based on prologue code analysis, as like as get_wchan() does. While the
code analysis might fail for some reason, there is a new kernel option
"raw_show_trace" to disable this feature.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/process.c')
| -rw-r--r-- | arch/mips/kernel/process.c | 66 |
1 files changed, 55 insertions, 11 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 7ab67f786bf..8709a46a45c 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -281,7 +281,7 @@ static struct mips_frame_info { } *schedule_frame, mfinfo[64]; static int mfinfo_num; -static int __init get_frame_info(struct mips_frame_info *info) +static int get_frame_info(struct mips_frame_info *info) { int i; void *func = info->func; @@ -329,14 +329,12 @@ static int __init get_frame_info(struct mips_frame_info *info) ip->i_format.simmediate / sizeof(long); } } - if (info->pc_offset == -1 || info->frame_size == 0) { - if (func == schedule) - printk("Can't analyze prologue code at %p\n", func); - info->pc_offset = -1; - info->frame_size = 0; - } - - return 0; + if (info->frame_size && info->pc_offset >= 0) /* nested */ + return 0; + if (info->pc_offset < 0) /* leaf */ + return 1; + /* prologue seems boggus... */ + return -1; } static int __init frame_info_init(void) @@ -367,8 +365,15 @@ static int __init frame_info_init(void) mfinfo[0].func = schedule; schedule_frame = &mfinfo[0]; #endif - for (i = 0; i < ARRAY_SIZE(mfinfo) && mfinfo[i].func; i++) - get_frame_info(&mfinfo[i]); + for (i = 0; i < ARRAY_SIZE(mfinfo) && mfinfo[i].func; i++) { + struct mips_frame_info *info = &mfinfo[i]; + if (get_frame_info(info)) { + /* leaf or unknown */ + if (info->func == schedule) + printk("Can't analyze prologue code at %p\n", + info->func); + } + } mfinfo_num = i; return 0; @@ -427,6 +432,8 @@ unsigned long get_wchan(struct task_struct *p) if (i < 0) break; + if (mfinfo[i].pc_offset < 0) + break; pc = ((unsigned long *)frame)[mfinfo[i].pc_offset]; if (!mfinfo[i].frame_size) break; @@ -437,3 +444,40 @@ unsigned long get_wchan(struct task_struct *p) return pc; } +#ifdef CONFIG_KALLSYMS +/* used by show_frametrace() */ +unsigned long unwind_stack(struct task_struct *task, + unsigned long **sp, unsigned long pc) +{ + unsigned long stack_page; + struct mips_frame_info info; + char *modname; + char namebuf[KSYM_NAME_LEN + 1]; + unsigned long size, ofs; + + stack_page = (unsigned long)task_stack_page(task); + if (!stack_page) + return 0; + + if (!kallsyms_lookup(pc, &size, &ofs, &modname, namebuf)) + return 0; + if (ofs == 0) + return 0; + + info.func = (void *)(pc - ofs); + info.func_size = ofs; /* analyze from start to ofs */ + if (get_frame_info(&info)) { + /* leaf or unknown */ + *sp += info.frame_size / sizeof(long); + return 0; + } + if ((unsigned long)*sp < stack_page || + (unsigned long)*sp + info.frame_size / sizeof(long) > + stack_page + THREAD_SIZE - 32) + return 0; + + pc = (*sp)[info.pc_offset]; + *sp += info.frame_size / sizeof(long); + return pc; +} +#endif |