From e0892e086aae8d86e33dc8fb87f3d36c901df574 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 29 Jun 2017 12:59:32 -0700 Subject: ipc: Replace spin_unlock_wait() with lock/unlock pair There is no agreed-upon definition of spin_unlock_wait()'s semantics, and it appears that all callers could do just as well with a lock/unlock pair. This commit therefore replaces the spin_unlock_wait() call in exit_sem() with spin_lock() followed immediately by spin_unlock(). This should be safe from a performance perspective because exit_sem() is rarely invoked in production. Signed-off-by: Paul E. McKenney Cc: Andrew Morton Cc: Davidlohr Bueso Cc: Will Deacon Cc: Peter Zijlstra Cc: Alan Stern Cc: Andrea Parri Cc: Linus Torvalds Acked-by: Manfred Spraul --- ipc/sem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'ipc') diff --git a/ipc/sem.c b/ipc/sem.c index 9e70cd7a17da..2570830e29fc 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -2091,7 +2091,8 @@ void exit_sem(struct task_struct *tsk) * possibility where we exit while freeary() didn't * finish unlocking sem_undo_list. */ - spin_unlock_wait(&ulp->lock); + spin_lock(&ulp->lock); + spin_unlock(&ulp->lock); rcu_read_unlock(); break; } -- cgit v1.2.3-58-ga151