diff options
author | Atsushi Nemoto <anemo@mba.ocn.ne.jp> | 2006-02-07 11:48:03 -0500 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2006-02-14 14:13:24 -0500 |
commit | 63077519899721120b61d663a68adced068a459d (patch) | |
tree | 54ed1587edae13a209f4cd2754ce4487fc3d6376 | |
parent | 1bdfd0d9632f0254a4fc01d17c9933ae6107dec4 (diff) |
[MIPS] Rewrite get_wchan and its helper functions using kallsyms_lookup.
Implement get_wchan() and frame_info_init() using kallsyms_lookup().
This fixes problem with static sched/lock functions and mfinfo[]
maintenance issue. If CONFIG_KALLSYMS was disabled, get_wchan() just
returns thread_saved_pc() value.
Also unwind stackframe based on "addiu sp,-imm" analysis instead of
frame pointer. This fixes problem with functions compiled without
-fomit-frame-pointer.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
-rw-r--r-- | arch/mips/kernel/process.c | 158 |
1 files changed, 77 insertions, 81 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 5232fc752935..092679c2dca9 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c | |||
@@ -25,6 +25,7 @@ | |||
25 | #include <linux/a.out.h> | 25 | #include <linux/a.out.h> |
26 | #include <linux/init.h> | 26 | #include <linux/init.h> |
27 | #include <linux/completion.h> | 27 | #include <linux/completion.h> |
28 | #include <linux/kallsyms.h> | ||
28 | 29 | ||
29 | #include <asm/abi.h> | 30 | #include <asm/abi.h> |
30 | #include <asm/bootinfo.h> | 31 | #include <asm/bootinfo.h> |
@@ -272,46 +273,19 @@ long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) | |||
272 | 273 | ||
273 | static struct mips_frame_info { | 274 | static struct mips_frame_info { |
274 | void *func; | 275 | void *func; |
275 | int omit_fp; /* compiled without fno-omit-frame-pointer */ | 276 | unsigned long func_size; |
276 | int frame_offset; | 277 | int frame_size; |
277 | int pc_offset; | 278 | int pc_offset; |
278 | } schedule_frame, mfinfo[] = { | 279 | } *schedule_frame, mfinfo[64]; |
279 | { schedule, 0 }, /* must be first */ | 280 | static int mfinfo_num; |
280 | /* arch/mips/kernel/semaphore.c */ | ||
281 | { __down, 1 }, | ||
282 | { __down_interruptible, 1 }, | ||
283 | /* kernel/sched.c */ | ||
284 | #ifdef CONFIG_PREEMPT | ||
285 | { preempt_schedule, 0 }, | ||
286 | #endif | ||
287 | { wait_for_completion, 0 }, | ||
288 | { interruptible_sleep_on, 0 }, | ||
289 | { interruptible_sleep_on_timeout, 0 }, | ||
290 | { sleep_on, 0 }, | ||
291 | { sleep_on_timeout, 0 }, | ||
292 | { yield, 0 }, | ||
293 | { io_schedule, 0 }, | ||
294 | { io_schedule_timeout, 0 }, | ||
295 | #if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT) | ||
296 | { __preempt_spin_lock, 0 }, | ||
297 | { __preempt_write_lock, 0 }, | ||
298 | #endif | ||
299 | /* kernel/timer.c */ | ||
300 | { schedule_timeout, 1 }, | ||
301 | /* { nanosleep_restart, 1 }, */ | ||
302 | /* lib/rwsem-spinlock.c */ | ||
303 | { __down_read, 1 }, | ||
304 | { __down_write, 1 }, | ||
305 | }; | ||
306 | 281 | ||
307 | static int mips_frame_info_initialized; | ||
308 | static int __init get_frame_info(struct mips_frame_info *info) | 282 | static int __init get_frame_info(struct mips_frame_info *info) |
309 | { | 283 | { |
310 | int i; | 284 | int i; |
311 | void *func = info->func; | 285 | void *func = info->func; |
312 | union mips_instruction *ip = (union mips_instruction *)func; | 286 | union mips_instruction *ip = (union mips_instruction *)func; |
313 | info->pc_offset = -1; | 287 | info->pc_offset = -1; |
314 | info->frame_offset = info->omit_fp ? 0 : -1; | 288 | info->frame_size = 0; |
315 | for (i = 0; i < 128; i++, ip++) { | 289 | for (i = 0; i < 128; i++, ip++) { |
316 | /* if jal, jalr, jr, stop. */ | 290 | /* if jal, jalr, jr, stop. */ |
317 | if (ip->j_format.opcode == jal_op || | 291 | if (ip->j_format.opcode == jal_op || |
@@ -320,6 +294,23 @@ static int __init get_frame_info(struct mips_frame_info *info) | |||
320 | ip->r_format.func == jr_op))) | 294 | ip->r_format.func == jr_op))) |
321 | break; | 295 | break; |
322 | 296 | ||
297 | if (info->func_size && i >= info->func_size / 4) | ||
298 | break; | ||
299 | if ( | ||
300 | #ifdef CONFIG_32BIT | ||
301 | ip->i_format.opcode == addiu_op && | ||
302 | #endif | ||
303 | #ifdef CONFIG_64BIT | ||
304 | ip->i_format.opcode == daddiu_op && | ||
305 | #endif | ||
306 | ip->i_format.rs == 29 && | ||
307 | ip->i_format.rt == 29) { | ||
308 | /* addiu/daddiu sp,sp,-imm */ | ||
309 | if (info->frame_size) | ||
310 | continue; | ||
311 | info->frame_size = - ip->i_format.simmediate; | ||
312 | } | ||
313 | |||
323 | if ( | 314 | if ( |
324 | #ifdef CONFIG_32BIT | 315 | #ifdef CONFIG_32BIT |
325 | ip->i_format.opcode == sw_op && | 316 | ip->i_format.opcode == sw_op && |
@@ -327,31 +318,20 @@ static int __init get_frame_info(struct mips_frame_info *info) | |||
327 | #ifdef CONFIG_64BIT | 318 | #ifdef CONFIG_64BIT |
328 | ip->i_format.opcode == sd_op && | 319 | ip->i_format.opcode == sd_op && |
329 | #endif | 320 | #endif |
330 | ip->i_format.rs == 29) | 321 | ip->i_format.rs == 29 && |
331 | { | 322 | ip->i_format.rt == 31) { |
332 | /* sw / sd $ra, offset($sp) */ | 323 | /* sw / sd $ra, offset($sp) */ |
333 | if (ip->i_format.rt == 31) { | 324 | if (info->pc_offset != -1) |
334 | if (info->pc_offset != -1) | 325 | continue; |
335 | continue; | 326 | info->pc_offset = |
336 | info->pc_offset = | 327 | ip->i_format.simmediate / sizeof(long); |
337 | ip->i_format.simmediate / sizeof(long); | ||
338 | } | ||
339 | /* sw / sd $s8, offset($sp) */ | ||
340 | if (ip->i_format.rt == 30) { | ||
341 | //#if 0 /* gcc 3.4 does aggressive optimization... */ | ||
342 | if (info->frame_offset != -1) | ||
343 | continue; | ||
344 | //#endif | ||
345 | info->frame_offset = | ||
346 | ip->i_format.simmediate / sizeof(long); | ||
347 | } | ||
348 | } | 328 | } |
349 | } | 329 | } |
350 | if (info->pc_offset == -1 || info->frame_offset == -1) { | 330 | if (info->pc_offset == -1 || info->frame_size == 0) { |
351 | printk("Can't analyze prologue code at %p\n", func); | 331 | if (func == schedule) |
332 | printk("Can't analyze prologue code at %p\n", func); | ||
352 | info->pc_offset = -1; | 333 | info->pc_offset = -1; |
353 | info->frame_offset = -1; | 334 | info->frame_size = 0; |
354 | return -1; | ||
355 | } | 335 | } |
356 | 336 | ||
357 | return 0; | 337 | return 0; |
@@ -359,25 +339,36 @@ static int __init get_frame_info(struct mips_frame_info *info) | |||
359 | 339 | ||
360 | static int __init frame_info_init(void) | 340 | static int __init frame_info_init(void) |
361 | { | 341 | { |
362 | int i, found; | 342 | int i; |
363 | for (i = 0; i < ARRAY_SIZE(mfinfo); i++) | 343 | #ifdef CONFIG_KALLSYMS |
364 | if (get_frame_info(&mfinfo[i])) | 344 | char *modname; |
365 | return -1; | 345 | char namebuf[KSYM_NAME_LEN + 1]; |
366 | schedule_frame = mfinfo[0]; | 346 | unsigned long start, size, ofs; |
367 | /* bubble sort */ | 347 | extern char __sched_text_start[], __sched_text_end[]; |
368 | do { | 348 | extern char __lock_text_start[], __lock_text_end[]; |
369 | struct mips_frame_info tmp; | 349 | |
370 | found = 0; | 350 | start = (unsigned long)__sched_text_start; |
371 | for (i = 1; i < ARRAY_SIZE(mfinfo); i++) { | 351 | for (i = 0; i < ARRAY_SIZE(mfinfo); i++) { |
372 | if (mfinfo[i-1].func > mfinfo[i].func) { | 352 | if (start == (unsigned long)schedule) |
373 | tmp = mfinfo[i]; | 353 | schedule_frame = &mfinfo[i]; |
374 | mfinfo[i] = mfinfo[i-1]; | 354 | if (!kallsyms_lookup(start, &size, &ofs, &modname, namebuf)) |
375 | mfinfo[i-1] = tmp; | 355 | break; |
376 | found = 1; | 356 | mfinfo[i].func = (void *)(start + ofs); |
377 | } | 357 | mfinfo[i].func_size = size; |
378 | } | 358 | start += size - ofs; |
379 | } while (found); | 359 | if (start >= (unsigned long)__lock_text_end) |
380 | mips_frame_info_initialized = 1; | 360 | break; |
361 | if (start == (unsigned long)__sched_text_end) | ||
362 | start = (unsigned long)__lock_text_start; | ||
363 | } | ||
364 | #else | ||
365 | mfinfo[0].func = schedule; | ||
366 | schedule_frame = &mfinfo[0]; | ||
367 | #endif | ||
368 | for (i = 0; i < ARRAY_SIZE(mfinfo) && mfinfo[i].func; i++) | ||
369 | get_frame_info(&mfinfo[i]); | ||
370 | |||
371 | mfinfo_num = i; | ||
381 | return 0; | 372 | return 0; |
382 | } | 373 | } |
383 | 374 | ||
@@ -394,47 +385,52 @@ unsigned long thread_saved_pc(struct task_struct *tsk) | |||
394 | if (t->reg31 == (unsigned long) ret_from_fork) | 385 | if (t->reg31 == (unsigned long) ret_from_fork) |
395 | return t->reg31; | 386 | return t->reg31; |
396 | 387 | ||
397 | if (schedule_frame.pc_offset < 0) | 388 | if (!schedule_frame || schedule_frame->pc_offset < 0) |
398 | return 0; | 389 | return 0; |
399 | return ((unsigned long *)t->reg29)[schedule_frame.pc_offset]; | 390 | return ((unsigned long *)t->reg29)[schedule_frame->pc_offset]; |
400 | } | 391 | } |
401 | 392 | ||
402 | /* get_wchan - a maintenance nightmare^W^Wpain in the ass ... */ | 393 | /* get_wchan - a maintenance nightmare^W^Wpain in the ass ... */ |
403 | unsigned long get_wchan(struct task_struct *p) | 394 | unsigned long get_wchan(struct task_struct *p) |
404 | { | 395 | { |
405 | unsigned long stack_page; | 396 | unsigned long stack_page; |
406 | unsigned long frame, pc; | 397 | unsigned long pc; |
398 | #ifdef CONFIG_KALLSYMS | ||
399 | unsigned long frame; | ||
400 | #endif | ||
407 | 401 | ||
408 | if (!p || p == current || p->state == TASK_RUNNING) | 402 | if (!p || p == current || p->state == TASK_RUNNING) |
409 | return 0; | 403 | return 0; |
410 | 404 | ||
411 | stack_page = (unsigned long)task_stack_page(p); | 405 | stack_page = (unsigned long)task_stack_page(p); |
412 | if (!stack_page || !mips_frame_info_initialized) | 406 | if (!stack_page || !mfinfo_num) |
413 | return 0; | 407 | return 0; |
414 | 408 | ||
415 | pc = thread_saved_pc(p); | 409 | pc = thread_saved_pc(p); |
410 | #ifdef CONFIG_KALLSYMS | ||
416 | if (!in_sched_functions(pc)) | 411 | if (!in_sched_functions(pc)) |
417 | return pc; | 412 | return pc; |
418 | 413 | ||
419 | frame = ((unsigned long *)p->thread.reg30)[schedule_frame.frame_offset]; | 414 | frame = p->thread.reg29 + schedule_frame->frame_size; |
420 | do { | 415 | do { |
421 | int i; | 416 | int i; |
422 | 417 | ||
423 | if (frame < stack_page || frame > stack_page + THREAD_SIZE - 32) | 418 | if (frame < stack_page || frame > stack_page + THREAD_SIZE - 32) |
424 | return 0; | 419 | return 0; |
425 | 420 | ||
426 | for (i = ARRAY_SIZE(mfinfo) - 1; i >= 0; i--) { | 421 | for (i = mfinfo_num - 1; i >= 0; i--) { |
427 | if (pc >= (unsigned long) mfinfo[i].func) | 422 | if (pc >= (unsigned long) mfinfo[i].func) |
428 | break; | 423 | break; |
429 | } | 424 | } |
430 | if (i < 0) | 425 | if (i < 0) |
431 | break; | 426 | break; |
432 | 427 | ||
433 | if (mfinfo[i].omit_fp) | ||
434 | break; | ||
435 | pc = ((unsigned long *)frame)[mfinfo[i].pc_offset]; | 428 | pc = ((unsigned long *)frame)[mfinfo[i].pc_offset]; |
436 | frame = ((unsigned long *)frame)[mfinfo[i].frame_offset]; | 429 | if (!mfinfo[i].frame_size) |
430 | break; | ||
431 | frame += mfinfo[i].frame_size; | ||
437 | } while (in_sched_functions(pc)); | 432 | } while (in_sched_functions(pc)); |
433 | #endif | ||
438 | 434 | ||
439 | return pc; | 435 | return pc; |
440 | } | 436 | } |