diff options
Diffstat (limited to 'kernel/futex.c')
| -rw-r--r-- | kernel/futex.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 4949d336d88..642f3bbaacc 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -150,7 +150,8 @@ static struct futex_hash_bucket *hash_futex(union futex_key *key) */ static inline int match_futex(union futex_key *key1, union futex_key *key2) { - return (key1->both.word == key2->both.word + return (key1 && key2 + && key1->both.word == key2->both.word && key1->both.ptr == key2->both.ptr && key1->both.offset == key2->both.offset); } @@ -1028,7 +1029,6 @@ static inline void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key, struct futex_hash_bucket *hb) { - drop_futex_key_refs(&q->key); get_futex_key_refs(key); q->key = *key; @@ -1226,6 +1226,7 @@ retry_private: */ if (ret == 1) { WARN_ON(pi_state); + drop_count++; task_count++; ret = get_futex_value_locked(&curval2, uaddr2); if (!ret) @@ -1304,6 +1305,7 @@ retry_private: if (ret == 1) { /* We got the lock. */ requeue_pi_wake_futex(this, &key2, hb2); + drop_count++; continue; } else if (ret) { /* -EDEADLK */ @@ -1791,6 +1793,7 @@ static int futex_wait(u32 __user *uaddr, int fshared, current->timer_slack_ns); } +retry: /* Prepare to wait on uaddr. */ ret = futex_wait_setup(uaddr, val, fshared, &q, &hb); if (ret) @@ -1808,9 +1811,14 @@ static int futex_wait(u32 __user *uaddr, int fshared, goto out_put_key; /* - * We expect signal_pending(current), but another thread may - * have handled it for us already. + * We expect signal_pending(current), but we might be the + * victim of a spurious wakeup as well. */ + if (!signal_pending(current)) { + put_futex_key(fshared, &q.key); + goto retry; + } + ret = -ERESTARTSYS; if (!abs_time) goto out_put_key; @@ -2118,9 +2126,11 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb, */ plist_del(&q->list, &q->list.plist); + /* Handle spurious wakeups gracefully */ + ret = -EAGAIN; if (timeout && !timeout->task) ret = -ETIMEDOUT; - else + else if (signal_pending(current)) ret = -ERESTARTNOINTR; } return ret; @@ -2198,6 +2208,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, debug_rt_mutex_init_waiter(&rt_waiter); rt_waiter.task = NULL; +retry: key2 = FUTEX_KEY_INIT; ret = get_futex_key(uaddr2, fshared, &key2, VERIFY_WRITE); if (unlikely(ret != 0)) @@ -2292,6 +2303,9 @@ out_put_keys: out_key2: put_futex_key(fshared, &key2); + /* Spurious wakeup ? */ + if (ret == -EAGAIN) + goto retry; out: if (to) { hrtimer_cancel(&to->timer); |