diff options
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 4d46e90f59c..4e7efac7b1e 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -237,6 +237,7 @@ struct runqueue { task_t *migration_thread; struct list_head migration_queue; + int cpu; #endif #ifdef CONFIG_SCHEDSTATS @@ -1660,6 +1661,9 @@ unsigned long nr_iowait(void) /* * double_rq_lock - safely lock two runqueues * + * We must take them in cpu order to match code in + * dependent_sleeper and wake_dependent_sleeper. + * * Note this does not disable interrupts like task_rq_lock, * you need to do so manually before calling. */ @@ -1671,7 +1675,7 @@ static void double_rq_lock(runqueue_t *rq1, runqueue_t *rq2) spin_lock(&rq1->lock); __acquire(rq2->lock); /* Fake it out ;) */ } else { - if (rq1 < rq2) { + if (rq1->cpu < rq2->cpu) { spin_lock(&rq1->lock); spin_lock(&rq2->lock); } else { @@ -1707,7 +1711,7 @@ static void double_lock_balance(runqueue_t *this_rq, runqueue_t *busiest) __acquires(this_rq->lock) { if (unlikely(!spin_trylock(&busiest->lock))) { - if (busiest < this_rq) { + if (busiest->cpu < this_rq->cpu) { spin_unlock(&this_rq->lock); spin_lock(&busiest->lock); spin_lock(&this_rq->lock); @@ -6035,6 +6039,7 @@ void __init sched_init(void) rq->push_cpu = 0; rq->migration_thread = NULL; INIT_LIST_HEAD(&rq->migration_queue); + rq->cpu = i; #endif atomic_set(&rq->nr_iowait, 0); |