From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> [ Upstream commit 29e9ee5d48c35d6cf8afe09bdf03f77125c9ac11 ] free_pi_state() is confusing as it is in fact only freeing/caching the pi state when the last reference is gone. Rename it to put_pi_state() which reflects better what it is doing. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Darren Hart <darren@xxxxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Cc: Bhuvanesh_Surachari@xxxxxxxxxx Cc: Andy Lowe <Andy_Lowe@xxxxxxxxxx> Link: http://lkml.kernel.org/r/20151219200607.259636467@xxxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx> Acked-by: Joe Korty <joe.korty@xxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/futex.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -859,9 +859,12 @@ static void pi_state_update_owner(struct } /* + * Drops a reference to the pi_state object and frees or caches it + * when the last reference is gone. + * * Must be called with the hb lock held. */ -static void free_pi_state(struct futex_pi_state *pi_state) +static void put_pi_state(struct futex_pi_state *pi_state) { if (!pi_state) return; @@ -2121,7 +2124,7 @@ retry_private: case 0: break; case -EFAULT: - free_pi_state(pi_state); + put_pi_state(pi_state); pi_state = NULL; double_unlock_hb(hb1, hb2); hb_waiters_dec(hb2); @@ -2139,7 +2142,7 @@ retry_private: * exit to complete. * - EAGAIN: The user space value changed. */ - free_pi_state(pi_state); + put_pi_state(pi_state); pi_state = NULL; double_unlock_hb(hb1, hb2); hb_waiters_dec(hb2); @@ -2214,7 +2217,7 @@ retry_private: } else if (ret) { /* -EDEADLK */ this->pi_state = NULL; - free_pi_state(pi_state); + put_pi_state(pi_state); goto out_unlock; } } @@ -2223,7 +2226,7 @@ retry_private: } out_unlock: - free_pi_state(pi_state); + put_pi_state(pi_state); double_unlock_hb(hb1, hb2); wake_up_q(&wake_q); hb_waiters_dec(hb2); @@ -2376,7 +2379,7 @@ static void unqueue_me_pi(struct futex_q __unqueue_futex(q); BUG_ON(!q->pi_state); - free_pi_state(q->pi_state); + put_pi_state(q->pi_state); q->pi_state = NULL; spin_unlock(q->lock_ptr); @@ -3210,7 +3213,7 @@ static int futex_wait_requeue_pi(u32 __u * Drop the reference to the pi state which * the requeue_pi() code acquired for us. */ - free_pi_state(q.pi_state); + put_pi_state(q.pi_state); spin_unlock(q.lock_ptr); /* * Adjust the return value. It's either -EFAULT or