softlockup: fix NMI hangs due to lock race - 2.6.26-rc regression

[linux-2.6-omap-h63xx.git] / kernel / softlockup.c

diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index a3a0b239b7f770a1346c407052d90b5b28be56d1..6b682d86bddf606c4342641204d673a6df3a6ff6 100644 (file)
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -64,12 +64,17 @@ static unsigned long get_timestamp(int this_cpu)
        return cpu_clock(this_cpu) >> 30LL;  /* 2^30 ~= 10^9 */
 }
 
-void touch_softlockup_watchdog(void)
+static void __touch_softlockup_watchdog(void)
 {
        int this_cpu = raw_smp_processor_id();
 
        __raw_get_cpu_var(touch_timestamp) = get_timestamp(this_cpu);
 }
+
+void touch_softlockup_watchdog(void)
+{
+       __raw_get_cpu_var(touch_timestamp) = 0;
+}
 EXPORT_SYMBOL(touch_softlockup_watchdog);
 
 void touch_all_softlockup_watchdogs(void)
@@ -103,7 +108,7 @@ void softlockup_tick(void)
        }
 
        if (touch_timestamp == 0) {
-               touch_softlockup_watchdog();
+               __touch_softlockup_watchdog();
                return;
        }
 
@@ -118,7 +123,7 @@ void softlockup_tick(void)
 
        /* do not print during early bootup: */
        if (unlikely(system_state != SYSTEM_RUNNING)) {
-               touch_softlockup_watchdog();
+               __touch_softlockup_watchdog();
                return;
        }
 
@@ -243,7 +248,7 @@ static int watchdog(void *__bind_cpu)
        sched_setscheduler(current, SCHED_FIFO, &param);
 
        /* initialize timestamp */
-       touch_softlockup_watchdog();
+       __touch_softlockup_watchdog();
 
        set_current_state(TASK_INTERRUPTIBLE);
        /*
@@ -252,7 +257,7 @@ static int watchdog(void *__bind_cpu)
         * debug-printout triggers in softlockup_tick().
         */
        while (!kthread_should_stop()) {
-               touch_softlockup_watchdog();
+               __touch_softlockup_watchdog();
                schedule();
 
                if (kthread_should_stop())