[PATCH 05/11] ia64, rwsem: provide __down_write_killable

Michal Hocko
2016-02-29T12:58:19Z

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/ia64/include/asm/rwsem.h | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/arch/ia64/include/asm/rwsem.h b/arch/ia64/include/asm/rwsem.h
index 3027e7516d85..5e78cb40d9df 100644
--- a/arch/ia64/include/asm/rwsem.h
+++ b/arch/ia64/include/asm/rwsem.h
@@ -49,8 +49,8 @@ __down_read (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)
{
long old, new;

@@ -59,10 +59,26 @@ __down_write (struct rw_semaphore *sem)
new = old + RWSEM_ACTIVE_WRITE_BIAS;
} while (cmpxchg_acq(&sem->count, old, new) != old);

- 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;
+}
+
/*
* unlock after reading
*/
--
2.7.0