Merge pull request #565 from philschenker/update-to-5.4.193__update-to-2.3.7__5.4-2.3.x-imx

Update Patchlevel on Branch 5.4-2.3.x-imx from 5.4.161->5.4.193

1 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index bed9e43f9426..46139c0f510f 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -22,6 +22,7 @@
 #include <linux/atomic.h>
 #include <linux/kthread.h>
 #include <linux/fs.h>
+#include <linux/blkdev.h>
 
 /* percpu_counter batch for blkg_[rw]stats, per-cpu drift doesn't matter */
 #define BLKG_STAT_CPU_BATCH	(INT_MAX / 2)
@@ -768,6 +769,21 @@ static inline void blkcg_use_delay(struct blkcg_gq *blkg)
 		atomic_inc(&blkg->blkcg->css.cgroup->congestion_count);
 }
 
+/**
+ * blk_cgroup_mergeable - Determine whether to allow or disallow merges
+ * @rq: request to merge into
+ * @bio: bio to merge
+ *
+ * @bio and @rq should belong to the same cgroup and their issue_as_root should
+ * match. The latter is necessary as we don't want to throttle e.g. a metadata
+ * update because it happens to be next to a regular IO.
+ */
+static inline bool blk_cgroup_mergeable(struct request *rq, struct bio *bio)
+{
+	return rq->bio->bi_blkg == bio->bi_blkg &&
+		bio_issue_as_root_blkg(rq->bio) == bio_issue_as_root_blkg(bio);
+}
+
 static inline int blkcg_unuse_delay(struct blkcg_gq *blkg)
 {
 	int old = atomic_read(&blkg->use_delay);
@@ -868,6 +884,7 @@ static inline bool blkcg_punt_bio_submit(struct bio *bio) { return false; }
 static inline void blkcg_bio_issue_init(struct bio *bio) { }
 static inline bool blkcg_bio_issue_check(struct request_queue *q,
 					 struct bio *bio) { return true; }
+static inline bool blk_cgroup_mergeable(struct request *rq, struct bio *bio) { return true; }
 
 #define blk_queue_for_each_rl(rl, q)	\
 	for ((rl) = &(q)->root_rl; (rl); (rl) = NULL)