From: Chunguang Xu <brookxu@xxxxxxxxxxx>
When calling blkcg_schedule_throttle(), for the same queue,
redundant get/put operations can be removed.
Signed-off-by: Chunguang Xu <brookxu@xxxxxxxxxxx>
---
block/blk-cgroup.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 031114d..e9b264b 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1757,12 +1757,15 @@ void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay)
if (unlikely(current->flags & PF_KTHREAD))
return;
- if (!blk_get_queue(q))
- return;
+ if (current->throttle_queue != q) {
+ if (!blk_get_queue(q))
+ return;
+
+ if (current->throttle_queue)
+ blk_put_queue(current->throttle_queue);
+ current->throttle_queue = q;
+ }
- if (current->throttle_queue)
- blk_put_queue(current->throttle_queue);
- current->throttle_queue = q;
if (use_memdelay)
current->use_memdelay = use_memdelay;
set_notify_resume(current);
--
1.8.3.1
