Merge branch 'akpm' (patches from Andrew)

[linux-2.6-microblaze.git] / kernel / hung_task.c

diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 32b4794..b9132d1 100644 (file)
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -40,6 +40,11 @@ int __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;
  */
 unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_TASK_TIMEOUT;
 
+/*
+ * Zero (default value) means use sysctl_hung_task_timeout_secs:
+ */
+unsigned long __read_mostly sysctl_hung_task_check_interval_secs;
+
 int __read_mostly sysctl_hung_task_warnings = 10;
 
 static int __read_mostly did_panic;
@@ -98,8 +103,11 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
 
        if (switch_count != t->last_switch_count) {
                t->last_switch_count = switch_count;
+               t->last_switch_time = jiffies;
                return;
        }
+       if (time_is_after_jiffies(t->last_switch_time + timeout * HZ))
+               return;
 
        trace_sched_process_hang(t);
 
@@ -245,8 +253,13 @@ static int watchdog(void *dummy)
 
        for ( ; ; ) {
                unsigned long timeout = sysctl_hung_task_timeout_secs;
-               long t = hung_timeout_jiffies(hung_last_checked, timeout);
+               unsigned long interval = sysctl_hung_task_check_interval_secs;
+               long t;
 
+               if (interval == 0)
+                       interval = timeout;
+               interval = min_t(unsigned long, interval, timeout);
+               t = hung_timeout_jiffies(hung_last_checked, interval);
                if (t <= 0) {
                        if (!atomic_xchg(&reset_hung_task, 0))
                                check_hung_uninterruptible_tasks(timeout);