[PATCH] s390: atomic primitives
Hugh Dickins <hugh@veritas.com>
Fix the broken atomic_cmpxchg primitive. Add atomic_sub_and_test,
atomic64_sub_return, atomic64_sub_and_test, atomic64_cmpxchg,
atomic64_add_unless and atomic64_inc_not_zero. Replace old style
atomic_compare_and_swap by atomic_cmpxchg. Shorten the whole header by
defining most primitives with the two inline functions atomic_add_return and
atomic_sub_return.
In addition this patch contains the s390 related fixes of Hugh's "mm: fill
arch atomic64 gaps" patch.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
index 1efc9f2..482e07e 100644
--- a/drivers/s390/char/tape_block.c
+++ b/drivers/s390/char/tape_block.c
@@ -65,7 +65,7 @@
tapeblock_trigger_requeue(struct tape_device *device)
{
/* Protect against rescheduling. */
- if (atomic_compare_and_swap(0, 1, &device->blk_data.requeue_scheduled))
+ if (atomic_cmpxchg(&device->blk_data.requeue_scheduled, 0, 1) != 0)
return;
schedule_work(&device->blk_data.requeue_task);
}