cpumask: centralize cpu_online_map and cpu_possible_map

[safe/jmp/linux-2.6] / kernel / softlockup.c

diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 97977ec..dc0b3be 100644 (file)
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -116,11 +116,8 @@ void softlockup_tick(void)
        print_timestamp = per_cpu(print_timestamp, this_cpu);
 
        /* report at most once a second */
-       if ((print_timestamp >= touch_timestamp &&
-                       print_timestamp < (touch_timestamp + 1)) ||
-                       did_panic) {
+       if (print_timestamp == touch_timestamp || did_panic)
                return;
-       }
 
        /* do not print during early bootup: */
        if (unlikely(system_state != SYSTEM_RUNNING)) {
@@ -130,8 +127,11 @@ void softlockup_tick(void)
 
        now = get_timestamp(this_cpu);
 
-       /* Wake up the high-prio watchdog task every second: */
-       if (now > (touch_timestamp + 1))
+       /*
+        * Wake up the high-prio watchdog task twice per
+        * threshold timespan.
+        */
+       if (now > touch_timestamp + softlockup_thresh/2)
                wake_up_process(per_cpu(watchdog_task, this_cpu));
 
        /* Warn about unreasonable delays: */
@@ -188,7 +188,7 @@ static void check_hung_task(struct task_struct *t, unsigned long now)
        if ((long)(now - t->last_switch_timestamp) <
                                        sysctl_hung_task_timeout_secs)
                return;
-       if (sysctl_hung_task_warnings < 0)
+       if (!sysctl_hung_task_warnings)
                return;
        sysctl_hung_task_warnings--;
 
@@ -226,14 +226,15 @@ static void check_hung_uninterruptible_tasks(int this_cpu)
         * If the system crashed already then all bets are off,
         * do not report extra hung tasks:
         */
-       if ((tainted & TAINT_DIE) || did_panic)
+       if (test_taint(TAINT_DIE) || did_panic)
                return;
 
        read_lock(&tasklist_lock);
        do_each_thread(g, t) {
                if (!--max_count)
                        goto unlock;
-               if (t->state & TASK_UNINTERRUPTIBLE)
+               /* 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:
@@ -338,14 +339,33 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
        .notifier_call = cpu_callback
 };
 
-__init void spawn_softlockup_task(void)
+static int __initdata nosoftlockup;
+
+static int __init nosoftlockup_setup(char *str)
+{
+       nosoftlockup = 1;
+       return 1;
+}
+__setup("nosoftlockup", nosoftlockup_setup);
+
+static int __init spawn_softlockup_task(void)
 {
        void *cpu = (void *)(long)smp_processor_id();
-       int err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
+       int err;
+
+       if (nosoftlockup)
+               return 0;
 
-       BUG_ON(err == NOTIFY_BAD);
+       err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
+       if (err == NOTIFY_BAD) {
+               BUG();
+               return 1;
+       }
        cpu_callback(&cpu_nfb, CPU_ONLINE, cpu);
        register_cpu_notifier(&cpu_nfb);
 
        atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
+
+       return 0;
 }
+early_initcall(spawn_softlockup_task);