diff options
Diffstat (limited to 'kernel/futex.c')
-rw-r--r-- | kernel/futex.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 0672ff88f159..8cc3ee1363a0 100644 --- a/kernel/futex.c +++ b/kernel/futex.c | |||
@@ -1010,15 +1010,19 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1, | |||
1010 | * requeue_pi_wake_futex() - Wake a task that acquired the lock during requeue | 1010 | * requeue_pi_wake_futex() - Wake a task that acquired the lock during requeue |
1011 | * q: the futex_q | 1011 | * q: the futex_q |
1012 | * key: the key of the requeue target futex | 1012 | * key: the key of the requeue target futex |
1013 | * hb: the hash_bucket of the requeue target futex | ||
1013 | * | 1014 | * |
1014 | * During futex_requeue, with requeue_pi=1, it is possible to acquire the | 1015 | * During futex_requeue, with requeue_pi=1, it is possible to acquire the |
1015 | * target futex if it is uncontended or via a lock steal. Set the futex_q key | 1016 | * target futex if it is uncontended or via a lock steal. Set the futex_q key |
1016 | * to the requeue target futex so the waiter can detect the wakeup on the right | 1017 | * to the requeue target futex so the waiter can detect the wakeup on the right |
1017 | * futex, but remove it from the hb and NULL the rt_waiter so it can detect | 1018 | * futex, but remove it from the hb and NULL the rt_waiter so it can detect |
1018 | * atomic lock acquisition. Must be called with the q->lock_ptr held. | 1019 | * atomic lock acquisition. Set the q->lock_ptr to the requeue target hb->lock |
1020 | * to protect access to the pi_state to fixup the owner later. Must be called | ||
1021 | * with both q->lock_ptr and hb->lock held. | ||
1019 | */ | 1022 | */ |
1020 | static inline | 1023 | static inline |
1021 | void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key) | 1024 | void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key, |
1025 | struct futex_hash_bucket *hb) | ||
1022 | { | 1026 | { |
1023 | drop_futex_key_refs(&q->key); | 1027 | drop_futex_key_refs(&q->key); |
1024 | get_futex_key_refs(key); | 1028 | get_futex_key_refs(key); |
@@ -1030,6 +1034,11 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key) | |||
1030 | WARN_ON(!q->rt_waiter); | 1034 | WARN_ON(!q->rt_waiter); |
1031 | q->rt_waiter = NULL; | 1035 | q->rt_waiter = NULL; |
1032 | 1036 | ||
1037 | q->lock_ptr = &hb->lock; | ||
1038 | #ifdef CONFIG_DEBUG_PI_LIST | ||
1039 | q->list.plist.lock = &hb->lock; | ||
1040 | #endif | ||
1041 | |||
1033 | wake_up_state(q->task, TASK_NORMAL); | 1042 | wake_up_state(q->task, TASK_NORMAL); |
1034 | } | 1043 | } |
1035 | 1044 | ||
@@ -1088,7 +1097,7 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex, | |||
1088 | ret = futex_lock_pi_atomic(pifutex, hb2, key2, ps, top_waiter->task, | 1097 | ret = futex_lock_pi_atomic(pifutex, hb2, key2, ps, top_waiter->task, |
1089 | set_waiters); | 1098 | set_waiters); |
1090 | if (ret == 1) | 1099 | if (ret == 1) |
1091 | requeue_pi_wake_futex(top_waiter, key2); | 1100 | requeue_pi_wake_futex(top_waiter, key2, hb2); |
1092 | 1101 | ||
1093 | return ret; | 1102 | return ret; |
1094 | } | 1103 | } |
@@ -1273,7 +1282,7 @@ retry_private: | |||
1273 | this->task, 1); | 1282 | this->task, 1); |
1274 | if (ret == 1) { | 1283 | if (ret == 1) { |
1275 | /* We got the lock. */ | 1284 | /* We got the lock. */ |
1276 | requeue_pi_wake_futex(this, &key2); | 1285 | requeue_pi_wake_futex(this, &key2, hb2); |
1277 | continue; | 1286 | continue; |
1278 | } else if (ret) { | 1287 | } else if (ret) { |
1279 | /* -EDEADLK */ | 1288 | /* -EDEADLK */ |