Re: [PATCH v2] hung_task: Add per-round stack trace deduplication
kernel test robot <[email protected]>
| Newsgroups | dev.linux.lists.oe-kbuild-all,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Hi Aaron, kernel test robot noticed the following build errors: [auto build test ERROR on akpm-mm/mm-everything] [also build test ERROR on linus/master v7.2-rc7 next-20260813] [cannot apply to linux-review/Aaron-Tomlin/hung_task-Add-per-round-stack-trace-deduplication/20260618-025656] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Aaron-Tomlin/hung_task-Add-per-round-stack-trace-deduplication/20260814-211006 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/20260620013559.1537893-1-atomlin%40atomlin.com patch subject: [PATCH v2] hung_task: Add per-round stack trace deduplication config: alpha-allmodconfig (https://download.01.org/0day-ci/archive/20260815/[email protected]/config) compiler: alpha-linux-gcc (GCC) 16.1.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260815/[email protected]/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <[email protected]> | Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ All errors (new ones prefixed by >>): In file included from <command-line>: kernel/hung_task.c: In function 'check_hung_uninterruptible_tasks': >> kernel/hung_task.c:388:72: error: 'sysctl_hung_task_dedup' undeclared (first use in this function); did you mean 'sysctl_hung_task_panic'? 388 | bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; | ^~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler_types.h:682:23: note: in definition of macro '__compiletime_assert' 682 | if (!(condition)) \ | ^~~~~~~~~ include/linux/compiler_types.h:702:9: note: in expansion of macro '_compiletime_assert' 702 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~ include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type' 49 | compiletime_assert_rwonce_type(x); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/hung_task.c:388:62: note: in expansion of macro 'READ_ONCE' 388 | bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; | ^~~~~~~~~ kernel/hung_task.c:388:72: note: each undeclared identifier is reported only once for each function it appears in include/linux/compiler_types.h:682:23: note: in definition of macro '__compiletime_assert' 682 | if (!(condition)) \ | ^~~~~~~~~ include/linux/compiler_types.h:702:9: note: in expansion of macro '_compiletime_assert' 702 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~ include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type' 49 | compiletime_assert_rwonce_type(x); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/hung_task.c:388:62: note: in expansion of macro 'READ_ONCE' 388 | bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; | ^~~~~~~~~ vim +388 kernel/hung_task.c 375 376 /* 377 * Check whether a TASK_UNINTERRUPTIBLE does not get woken up for 378 * a really long time. If that happens, print out a warning. 379 */ 380 static void check_hung_uninterruptible_tasks(unsigned long timeout) 381 { 382 int max_count = sysctl_hung_task_check_count; 383 unsigned long last_break = jiffies; 384 struct task_struct *g, *t; 385 unsigned long this_round_count; 386 int need_warning = sysctl_hung_task_warnings; 387 unsigned long si_mask = hung_task_si_mask; > 388 bool dedup_enabled = IS_ENABLED(CONFIG_STACKTRACE) ? READ_ONCE(sysctl_hung_task_dedup) : 0; 389 390 /* 391 * If the system crashed already then all bets are off, 392 * do not report extra hung tasks: 393 */ 394 if (test_taint(TAINT_DIE) || did_panic) 395 return; 396 397 /* 398 * Reset the de-duplicator hash table for this new detection round. 399 * This prevents stale hashes from permanently suppressing. 400 */ 401 if (dedup_enabled) 402 hung_task_dedup_flush(); 403 404 this_round_count = 0; 405 rcu_read_lock(); 406 for_each_process_thread(g, t) { 407 if (!max_count--) 408 goto unlock; 409 if (time_after(jiffies, last_break + HUNG_TASK_LOCK_BREAK)) { 410 if (!rcu_lock_break(g, t)) 411 goto unlock; 412 last_break = jiffies; 413 } 414 415 if (task_is_hung(t, timeout)) { 416 /* 417 * Increment the global counter so that userspace could 418 * start migrating tasks ASAP. But count the current 419 * round separately because userspace could reset 420 * the global counter at any time. 421 */ 422 atomic_long_inc(&sysctl_hung_task_detect_count); 423 this_round_count++; 424 hung_task_info(t, timeout, this_round_count, dedup_enabled); 425 } 426 } 427 unlock: 428 rcu_read_unlock(); 429 430 if (!this_round_count) 431 return; 432 433 if (need_warning || hung_task_call_panic) { 434 si_mask |= SYS_INFO_LOCKS; 435 436 if (sysctl_hung_task_all_cpu_backtrace) 437 si_mask |= SYS_INFO_ALL_BT; 438 } 439 440 sys_info(si_mask); 441 442 if (hung_task_call_panic) 443 panic("hung_task: blocked tasks"); 444 } 445 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki