Merge branches 'release', 'APERF', 'ARAT', 'misc', 'kelvin', 'device-lock' and 'bjorn...

[sfrench/cifs-2.6.git] / kernel / softlockup.c

diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 85d5a2455103397015973321359a45e7d6d1928d..88796c330838dd66c24b8628f8b56ce27d3a3d23 100644 (file)
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -165,98 +165,12 @@ void softlockup_tick(void)
                panic("softlockup: hung tasks");
 }
 
-/*
- * Have a reasonable limit on the number of tasks checked:
- */
-unsigned long __read_mostly sysctl_hung_task_check_count = 1024;
-
-/*
- * Zero means infinite timeout - no checking done:
- */
-unsigned long __read_mostly sysctl_hung_task_timeout_secs = 480;
-
-unsigned long __read_mostly sysctl_hung_task_warnings = 10;
-
-/*
- * Only do the hung-tasks check on one CPU:
- */
-static int check_cpu __read_mostly = -1;
-
-static void check_hung_task(struct task_struct *t, unsigned long now)
-{
-       unsigned long switch_count = t->nvcsw + t->nivcsw;
-
-       if (t->flags & PF_FROZEN)
-               return;
-
-       if (switch_count != t->last_switch_count || !t->last_switch_timestamp) {
-               t->last_switch_count = switch_count;
-               t->last_switch_timestamp = now;
-               return;
-       }
-       if ((long)(now - t->last_switch_timestamp) <
-                                       sysctl_hung_task_timeout_secs)
-               return;
-       if (!sysctl_hung_task_warnings)
-               return;
-       sysctl_hung_task_warnings--;
-
-       /*
-        * Ok, the task did not get scheduled for more than 2 minutes,
-        * complain:
-        */
-       printk(KERN_ERR "INFO: task %s:%d blocked for more than "
-                       "%ld seconds.\n", t->comm, t->pid,
-                       sysctl_hung_task_timeout_secs);
-       printk(KERN_ERR "\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\""
-                       " disables this message.\n");
-       sched_show_task(t);
-       __debug_show_held_locks(t);
-
-       t->last_switch_timestamp = now;
-       touch_nmi_watchdog();
-
-       if (softlockup_panic)
-               panic("softlockup: blocked tasks");
-}
-
-/*
- * Check whether a TASK_UNINTERRUPTIBLE does not get woken up for
- * a really long time (120 seconds). If that happens, print out
- * a warning.
- */
-static void check_hung_uninterruptible_tasks(int this_cpu)
-{
-       int max_count = sysctl_hung_task_check_count;
-       unsigned long now = get_timestamp(this_cpu);
-       struct task_struct *g, *t;
-
-       /*
-        * If the system crashed already then all bets are off,
-        * do not report extra hung tasks:
-        */
-       if (test_taint(TAINT_DIE) || did_panic)
-               return;
-
-       read_lock(&tasklist_lock);
-       do_each_thread(g, t) {
-               if (!--max_count)
-                       goto unlock;
-               /* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */
-               if (t->state == TASK_UNINTERRUPTIBLE)
-                       check_hung_task(t, now);
-       } while_each_thread(g, t);
- unlock:
-       read_unlock(&tasklist_lock);
-}
-
 /*
  * The watchdog thread - runs every second and touches the timestamp.
  */
 static int watchdog(void *__bind_cpu)
 {
        struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
-       int this_cpu = (long)__bind_cpu;
 
        sched_setscheduler(current, SCHED_FIFO, &param);
 
@@ -276,11 +190,6 @@ static int watchdog(void *__bind_cpu)
                if (kthread_should_stop())
                        break;
 
-               if (this_cpu == check_cpu) {
-                       if (sysctl_hung_task_timeout_secs)
-                               check_hung_uninterruptible_tasks(this_cpu);
-               }
-
                set_current_state(TASK_INTERRUPTIBLE);
        }
        __set_current_state(TASK_RUNNING);
@@ -312,18 +221,9 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
                break;
        case CPU_ONLINE:
        case CPU_ONLINE_FROZEN:
-               check_cpu = cpumask_any(cpu_online_mask);
                wake_up_process(per_cpu(watchdog_task, hotcpu));
                break;
 #ifdef CONFIG_HOTPLUG_CPU
-       case CPU_DOWN_PREPARE:
-       case CPU_DOWN_PREPARE_FROZEN:
-               if (hotcpu == check_cpu) {
-                       /* Pick any other online cpu. */
-                       check_cpu = cpumask_any_but(cpu_online_mask, hotcpu);
-               }
-               break;
-
        case CPU_UP_CANCELED:
        case CPU_UP_CANCELED_FROZEN:
                if (!per_cpu(watchdog_task, hotcpu))