diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/core.c | 1 | ||||
| -rw-r--r-- | kernel/stop_machine.c | 27 |
2 files changed, 25 insertions, 3 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index d2003a7d5ab5..5e24104faafd 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6447,6 +6447,7 @@ void sched_show_task(struct task_struct *p) (unsigned long)task_thread_info(p)->flags); print_worker_info(KERN_INFO, p); + print_stop_info(KERN_INFO, p); show_stack(p, NULL, KERN_INFO); put_task_stack(p); } diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 865bb0228ab6..3cf567c2019d 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -42,11 +42,27 @@ struct cpu_stopper { struct list_head works; /* list of pending works */ struct cpu_stop_work stop_work; /* for stop_cpus */ + unsigned long caller; + cpu_stop_fn_t fn; }; static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper); static bool stop_machine_initialized = false; +void print_stop_info(const char *log_lvl, struct task_struct *task) +{ + /* + * If @task is a stopper task, it cannot migrate and task_cpu() is + * stable. + */ + struct cpu_stopper *stopper = per_cpu_ptr(&cpu_stopper, task_cpu(task)); + + if (task != stopper->thread) + return; + + printk("%sStopper: %pS <- %pS\n", log_lvl, stopper->fn, (void *)stopper->caller); +} + /* static data for stop_cpus */ static DEFINE_MUTEX(stop_cpus_mutex); static bool stop_cpus_in_progress; @@ -123,7 +139,7 @@ static bool cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work) int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg) { struct cpu_stop_done done; - struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done }; + struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done, .caller = _RET_IP_ }; cpu_stop_init_done(&done, 1); if (!cpu_stop_queue_work(cpu, &work)) @@ -331,7 +347,8 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void * work1 = work2 = (struct cpu_stop_work){ .fn = multi_cpu_stop, .arg = &msdata, - .done = &done + .done = &done, + .caller = _RET_IP_, }; cpu_stop_init_done(&done, 2); @@ -367,7 +384,7 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void * bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg, struct cpu_stop_work *work_buf) { - *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, }; + *work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, .caller = _RET_IP_, }; return cpu_stop_queue_work(cpu, work_buf); } @@ -487,6 +504,8 @@ repeat: int ret; /* cpu stop callbacks must not sleep, make in_atomic() == T */ + stopper->caller = work->caller; + stopper->fn = fn; preempt_count_inc(); ret = fn(arg); if (done) { @@ -495,6 +514,8 @@ repeat: cpu_stop_signal_done(done); } preempt_count_dec(); + stopper->fn = NULL; + stopper->caller = 0; WARN_ONCE(preempt_count(), "cpu_stop: %ps(%p) leaked preempt count\n", fn, arg); goto repeat; |