From a8618a0e8a06f75c6efec2a5477861d704d48b28 Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Mon, 9 Aug 2010 17:21:20 -0700 Subject: rwsem: smaller wrappers around rwsem_down_failed_common More code can be pushed from rwsem_down_read_failed and rwsem_down_write_failed into rwsem_down_failed_common. Following change adding down_read_critical infrastructure support also enjoys having flags available in a register rather than having to fish it out in the struct rwsem_waiter... Signed-off-by: Michel Lespinasse Acked-by: David Howells Cc: Mike Waychison Cc: Suleiman Souhlal Cc: Ying Han Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/rwsem.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) (limited to 'lib/rwsem.c') diff --git a/lib/rwsem.c b/lib/rwsem.c index 318d435dcebb..f236d7cd5cf3 100644 --- a/lib/rwsem.c +++ b/lib/rwsem.c @@ -171,8 +171,9 @@ __rwsem_do_wake(struct rw_semaphore *sem, int wake_type) */ static struct rw_semaphore __sched * rwsem_down_failed_common(struct rw_semaphore *sem, - struct rwsem_waiter *waiter, signed long adjustment) + unsigned int flags, signed long adjustment) { + struct rwsem_waiter waiter; struct task_struct *tsk = current; signed long count; @@ -180,12 +181,13 @@ rwsem_down_failed_common(struct rw_semaphore *sem, /* set up my own style of waitqueue */ spin_lock_irq(&sem->wait_lock); - waiter->task = tsk; + waiter.task = tsk; + waiter.flags = flags; get_task_struct(tsk); if (list_empty(&sem->wait_list)) adjustment += RWSEM_WAITING_BIAS; - list_add_tail(&waiter->list, &sem->wait_list); + list_add_tail(&waiter.list, &sem->wait_list); /* we're now waiting on the lock, but no longer actively locking */ count = rwsem_atomic_update(adjustment, sem); @@ -206,7 +208,7 @@ rwsem_down_failed_common(struct rw_semaphore *sem, /* wait to be given the lock */ for (;;) { - if (!waiter->task) + if (!waiter.task) break; schedule(); set_task_state(tsk, TASK_UNINTERRUPTIBLE); @@ -223,11 +225,8 @@ rwsem_down_failed_common(struct rw_semaphore *sem, asmregparm struct rw_semaphore __sched * rwsem_down_read_failed(struct rw_semaphore *sem) { - struct rwsem_waiter waiter; - - waiter.flags = RWSEM_WAITING_FOR_READ; - rwsem_down_failed_common(sem, &waiter, -RWSEM_ACTIVE_READ_BIAS); - return sem; + return rwsem_down_failed_common(sem, RWSEM_WAITING_FOR_READ, + -RWSEM_ACTIVE_READ_BIAS); } /* @@ -236,12 +235,8 @@ rwsem_down_read_failed(struct rw_semaphore *sem) asmregparm struct rw_semaphore __sched * rwsem_down_write_failed(struct rw_semaphore *sem) { - struct rwsem_waiter waiter; - - waiter.flags = RWSEM_WAITING_FOR_WRITE; - rwsem_down_failed_common(sem, &waiter, -RWSEM_ACTIVE_WRITE_BIAS); - - return sem; + return rwsem_down_failed_common(sem, RWSEM_WAITING_FOR_WRITE, + -RWSEM_ACTIVE_WRITE_BIAS); } /* -- cgit v1.2.3