[PATCH 06/11] s390, rwsem: provide __down_write_killable

Michal Hocko
2016-02-29T12:58:20Z

From: Michal Hocko <mhocko@suse.com>

Introduce ___down_write for the fast path and reuse it for __down_write
resp. __down_write_killable each using the respective generic slow path
(rwsem_down_write_failed resp. rwsem_down_write_failed_killable).

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
arch/s390/include/asm/rwsem.h | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/s390/include/asm/rwsem.h b/arch/s390/include/asm/rwsem.h
index 8e52e72f3efc..8e7b2b7e10f3 100644
--- a/arch/s390/include/asm/rwsem.h
+++ b/arch/s390/include/asm/rwsem.h
@@ -90,7 +90,7 @@ static inline int __down_read_trylock(struct rw_semaphore *sem)
/*
* lock for writing
*/
-static inline void __down_write(struct rw_semaphore *sem)
+static inline long ___down_write(struct rw_semaphore *sem)
{
signed long old, new, tmp;

@@ -104,10 +104,25 @@ static inline void __down_write(struct rw_semaphore *sem)
: "=&d" (old), "=&d" (new), "=Q" (sem->count)
: "Q" (sem->count), "m" (tmp)
: "cc", "memory");
- if (old != 0)
+
+ return old;
+}
+
+static inline void __down_write(struct rw_semaphore *sem)
+{
+ if (___down_write(sem))
rwsem_down_write_failed(sem);
}

+static inline int __down_write_killable(struct rw_semaphore *sem)
+{
+ if (___down_write(sem))
+ if (IS_ERR(rwsem_down_write_failed_killable(sem)))
+ return -EINTR;
+
+ return 0;
+}
+
/*
* trylock for writing -- returns 1 if successful, 0 if contention
*/
--
2.7.0