diff options
Diffstat (limited to 'kernel/hung_task.c')
| -rw-r--r-- | kernel/hung_task.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/kernel/hung_task.c b/kernel/hung_task.c index ba5a77cad3b..ba8ccd43296 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -72,7 +72,8 @@ static unsigned long get_timestamp(void) return cpu_clock(this_cpu) >> 30LL; /* 2^30 ~= 10^9 */ } -static void check_hung_task(struct task_struct *t, unsigned long now) +static void check_hung_task(struct task_struct *t, unsigned long now, + unsigned long timeout) { unsigned long switch_count = t->nvcsw + t->nivcsw; @@ -84,8 +85,7 @@ static void check_hung_task(struct task_struct *t, unsigned long now) t->last_switch_timestamp = now; return; } - if ((long)(now - t->last_switch_timestamp) < - sysctl_hung_task_timeout_secs) + if ((long)(now - t->last_switch_timestamp) < timeout) return; if (!sysctl_hung_task_warnings) return; @@ -96,8 +96,7 @@ static void check_hung_task(struct task_struct *t, unsigned long now) * complain: */ printk(KERN_ERR "INFO: task %s:%d blocked for more than " - "%ld seconds.\n", t->comm, t->pid, - sysctl_hung_task_timeout_secs); + "%ld seconds.\n", t->comm, t->pid, timeout); printk(KERN_ERR "\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\"" " disables this message.\n"); sched_show_task(t); @@ -115,7 +114,7 @@ static void check_hung_task(struct task_struct *t, unsigned long now) * a really long time (120 seconds). If that happens, print out * a warning. */ -static void check_hung_uninterruptible_tasks(void) +static void check_hung_uninterruptible_tasks(unsigned long timeout) { int max_count = sysctl_hung_task_check_count; unsigned long now = get_timestamp(); @@ -134,7 +133,7 @@ static void check_hung_uninterruptible_tasks(void) goto unlock; /* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */ if (t->state == TASK_UNINTERRUPTIBLE) - check_hung_task(t, now); + check_hung_task(t, now, timeout); } while_each_thread(g, t); unlock: read_unlock(&tasklist_lock); @@ -180,8 +179,17 @@ static int watchdog(void *dummy) update_poll_jiffies(); for ( ; ; ) { + unsigned long timeout; + while (schedule_timeout_interruptible(hung_task_poll_jiffies)); - check_hung_uninterruptible_tasks(); + + /* + * Need to cache timeout here to avoid timeout being set + * to 0 via sysctl while inside check_hung_*_tasks(). + */ + timeout = sysctl_hung_task_timeout_secs; + if (timeout) + check_hung_uninterruptible_tasks(timeout); } return 0; |