spinlock: lockbreak cleanup

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

diff --git a/kernel/sched.c b/kernel/sched.c
index 629614a..ba4c880 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -465,7 +465,7 @@ struct rq {
        u64 clock, prev_clock_raw;
        s64 clock_max_delta;
 
-       unsigned int clock_warps, clock_overflows;
+       unsigned int clock_warps, clock_overflows, clock_underflows;
        u64 idle_clock;
        unsigned int clock_deep_idle_events;
        u64 tick_timestamp;
@@ -858,7 +858,6 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
        struct rq *rq = cpu_rq(smp_processor_id());
        u64 now = sched_clock();
 
-       touch_softlockup_watchdog();
        rq->idle_clock += delta_ns;
        /*
         * Override the previous timestamp and ignore all
@@ -870,6 +869,7 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
        rq->prev_clock_raw = now;
        rq->clock += delta_ns;
        spin_unlock(&rq->lock);
+       touch_softlockup_watchdog();
 }
 EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
 
@@ -3736,8 +3736,10 @@ void scheduler_tick(void)
        /*
         * Let rq->clock advance by at least TICK_NSEC:
         */
-       if (unlikely(rq->clock < next_tick))
+       if (unlikely(rq->clock < next_tick)) {
                rq->clock = next_tick;
+               rq->clock_underflows++;
+       }
        rq->tick_timestamp = rq->clock;
        update_cpu_load(rq);
        curr->sched_class->task_tick(rq, curr, 0);
@@ -4943,19 +4945,15 @@ EXPORT_SYMBOL(_cond_resched);
  */
 int cond_resched_lock(spinlock_t *lock)
 {
+       int resched = need_resched() && system_state == SYSTEM_RUNNING;
        int ret = 0;
 
-       if (need_lockbreak(lock)) {
+       if (spin_needbreak(lock) || resched) {
                spin_unlock(lock);
-               cpu_relax();
-               ret = 1;
-               spin_lock(lock);
-       }
-       if (need_resched() && system_state == SYSTEM_RUNNING) {
-               spin_release(&lock->dep_map, 1, _THIS_IP_);
-               _raw_spin_unlock(lock);
-               preempt_enable_no_resched();
-               __cond_resched();
+               if (resched && need_resched())
+                       __cond_resched();
+               else
+                       cpu_relax();
                ret = 1;
                spin_lock(lock);
        }
@@ -5159,8 +5157,7 @@ void sched_show_task(struct task_struct *p)
        printk(KERN_CONT "%5lu %5d %6d\n", free,
                task_pid_nr(p), task_pid_nr(p->real_parent));
 
-       if (state != TASK_RUNNING)
-               show_stack(p, NULL);
+       show_stack(p, NULL);
 }
 
 void show_state_filter(unsigned long state_filter)