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Diffstat (limited to 'libpthread/sysdeps/generic/pt-rwlock-unlock.c')
-rw-r--r--libpthread/sysdeps/generic/pt-rwlock-unlock.c90
1 files changed, 0 insertions, 90 deletions
diff --git a/libpthread/sysdeps/generic/pt-rwlock-unlock.c b/libpthread/sysdeps/generic/pt-rwlock-unlock.c
deleted file mode 100644
index fb23a0b9..00000000
--- a/libpthread/sysdeps/generic/pt-rwlock-unlock.c
+++ /dev/null
@@ -1,90 +0,0 @@
-/* Unlock a rwlock. Generic version.
- Copyright (C) 2000,02 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-#include <pthread.h>
-
-#include <pt-internal.h>
-
-/* Unlock *RWLOCK, rescheduling a waiting writer thread or, if there
- are no threads waiting for a write lock, rescheduling the reader
- threads. */
-int
-pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
-{
- struct __pthread *wakeup;
-
- __pthread_spin_lock (&rwlock->__lock);
-
- assert (__pthread_spin_trylock (&rwlock->__held) == EBUSY);
-
- if (rwlock->readers > 1)
- /* There are other readers. */
- {
- rwlock->readers --;
- __pthread_spin_unlock (&rwlock->__lock);
- return 0;
- }
-
- if (rwlock->readers == 1)
- /* Last reader. */
- rwlock->readers = 0;
-
-
- /* Wake someone else up. Try the writer queue first, then the
- reader queue if that is empty. */
-
- if (rwlock->writerqueue)
- {
- wakeup = rwlock->writerqueue;
- __pthread_dequeue (wakeup);
-
- /* We do not unlock RWLOCK->held: we are transferring the ownership
- to the thread that we are waking up. */
-
- __pthread_spin_unlock (&rwlock->__lock);
- __pthread_wakeup (wakeup);
-
- return 0;
- }
-
- if (rwlock->readerqueue)
- {
- __pthread_queue_iterate (rwlock->readerqueue, wakeup)
- rwlock->readers ++;
-
- wakeup = rwlock->readerqueue;
- rwlock->readerqueue = 0;
-
- __pthread_spin_unlock (&rwlock->__lock);
-
- /* We can safely walk the list of waiting threads without holding
- the lock since it is now decoupled from the rwlock. */
- __pthread_dequeuing_iterate (wakeup, wakeup)
- __pthread_wakeup (wakeup);
-
- return 0;
- }
-
-
- /* Noone is waiting. Just unlock it. */
-
- __pthread_spin_unlock (&rwlock->__held);
- __pthread_spin_unlock (&rwlock->__lock);
- return 0;
-}