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Is there any reason why hung-task watchdog prints error header with KERN_ERR log level while task's backtrace is printed with KERN_INFO? Will it make sense to unify log levels and introduce sched_show_task() variant that accept log level param so that everything that hung-task watchdog prints becomes KERN_ERR? Something like this: --- include/linux/sched/debug.h | 1 + kernel/hung_task.c | 4 ++-- kernel/sched/core.c | 19 +++++++++++++------ 3 files changed, 16 insertions(+), 8 deletions(-) diff --git a/include/linux/sched/debug.h b/include/linux/sched/debug.h index b5035afa2396..8e46854d16fc 100644 --- a/include/linux/sched/debug.h +++ b/include/linux/sched/debug.h @@ -34,6 +34,7 @@ extern void show_stack(struct task_struct *task, unsigned= long *sp, const char *loglvl); =20 extern void sched_show_task(struct task_struct *p); +extern void sched_show_task_log_lvl(struct task_struct *p, const char *lvl= ); =20 #ifdef CONFIG_SCHED_DEBUG struct seq_file; diff --git a/kernel/hung_task.c b/kernel/hung_task.c index ccd7217fcec1..23dec32a05f3 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -119,7 +119,7 @@ static void debug_show_blocker(struct task_struct *task) if ((unsigned long)t =3D=3D owner) { pr_err("INFO: task %s:%d is blocked on a mutex likely owned by task %s:= %d.\n", task->comm, task->pid, t->comm, t->pid); - sched_show_task(t); + sched_show_task_log_lvl(t, KERN_ERR); return; } } @@ -186,7 +186,7 @@ static void check_hung_task(struct task_struct *t, unsi= gned long timeout) pr_err(" Blocked by coredump.\n"); pr_err("\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\"" " disables this message.\n"); - sched_show_task(t); + sched_show_task_log_lvl(t, KERN_ERR); debug_show_blocker(t); hung_task_show_lock =3D true; =20 diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 00ea6f31973c..b6a5a41fbbfc 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7687,7 +7687,7 @@ void __sched io_schedule(void) } EXPORT_SYMBOL(io_schedule); =20 -void sched_show_task(struct task_struct *p) +void sched_show_task_log_lvl(struct task_struct *p, const char *lvl) { unsigned long free; int ppid; @@ -7695,7 +7695,8 @@ void sched_show_task(struct task_struct *p) if (!try_get_task_stack(p)) return; =20 - pr_info("task:%-15.15s state:%c", p->comm, task_state_to_char(p)); + printk("%stask:%-15.15s state:%c", lvl, + p->comm, task_state_to_char(p)); =20 if (task_is_running(p)) pr_cont(" running task "); @@ -7709,12 +7710,18 @@ void sched_show_task(struct task_struct *p) free, task_pid_nr(p), task_tgid_nr(p), ppid, p->flags, read_task_thread_flags(p)); =20 - print_worker_info(KERN_INFO, p); - print_stop_info(KERN_INFO, p); - print_scx_info(KERN_INFO, p); - show_stack(p, NULL, KERN_INFO); + print_worker_info(lvl, p); + print_stop_info(lvl, p); + print_scx_info(lvl, p); + show_stack(p, NULL, lvl); put_task_stack(p); } +EXPORT_SYMBOL_GPL(sched_show_task_log_lvl); + +void sched_show_task(struct task_struct *p) +{ + sched_show_task_log_lvl(p, KERN_INFO); +} EXPORT_SYMBOL_GPL(sched_show_task); =20 static inline bool --=20 2.49.0.rc0.332.g42c0ae87b1-goog