[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>

2 files changed, 2 insertions, 2 deletions

diff --git a/drivers/s390/char/sclp_quiesce.c b/drivers/s390/char/sclp_quiesce.c
index 83f75774df60..56fa69168898 100644
--- a/drivers/s390/char/sclp_quiesce.c
+++ b/drivers/s390/char/sclp_quiesce.c
@@ -32,7 +32,7 @@ do_load_quiesce_psw(void * __unused)
         psw_t quiesce_psw;
         int cpu;
 
-        if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
+        if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) != -1)
                 signal_processor(smp_processor_id(), sigp_stop);
         /* Wait for all other cpus to enter stopped state */
         for_each_online_cpu(cpu) {
diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
index 1efc9f21229e..482e07e388c8 100644
--- a/drivers/s390/char/tape_block.c
+++ b/drivers/s390/char/tape_block.c
@@ -65,7 +65,7 @@ static void
 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);
 }