diff options
Diffstat (limited to 'kernel/futex.c')
-rw-r--r-- | kernel/futex.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index dbb38e14f6fc..dab9c79a931a 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -825,7 +825,7 @@ static int refill_pi_state_cache(void) return 0; } -static struct futex_pi_state * alloc_pi_state(void) +static struct futex_pi_state *alloc_pi_state(void) { struct futex_pi_state *pi_state = current->pi_state_cache; @@ -858,6 +858,11 @@ static void pi_state_update_owner(struct futex_pi_state *pi_state, } } +static void get_pi_state(struct futex_pi_state *pi_state) +{ + WARN_ON_ONCE(!atomic_inc_not_zero(&pi_state->refcount)); +} + /* * Drops a reference to the pi_state object and frees or caches it * when the last reference is gone. @@ -901,7 +906,7 @@ static void put_pi_state(struct futex_pi_state *pi_state) * Look up the task based on what TID userspace gave us. * We dont trust it. */ -static struct task_struct * futex_find_get_task(pid_t pid) +static struct task_struct *futex_find_get_task(pid_t pid) { struct task_struct *p; @@ -1149,7 +1154,7 @@ static int attach_to_pi_state(u32 __user *uaddr, u32 uval, goto out_einval; out_attach: - atomic_inc(&pi_state->refcount); + get_pi_state(pi_state); raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); *ps = pi_state; return 0; @@ -2204,7 +2209,7 @@ retry_private: */ if (requeue_pi) { /* Prepare the waiter to take the rt_mutex. */ - atomic_inc(&pi_state->refcount); + get_pi_state(pi_state); this->pi_state = pi_state; ret = rt_mutex_start_proxy_lock(&pi_state->pi_mutex, this->rt_waiter, |