---

yaml --- r: 196804 b: refs/heads/master c: 812d402 h: refs/heads/master v: v3
git-mirror · Apr 9, 2010 · 7cd8e0e · 7cd8e0e
1 parent 500ed7d
commit 7cd8e0e
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Showing 8 changed files with 58 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 84c124da9ff50bd71fab9c939ee5b7cd8bef2bd9
+refs/heads/master: 812d402648f4fc1ab1091b2172a46fc1b367c724
diff --git a/trunk/Documentation/cgroups/blkio-controller.txt b/trunk/Documentation/cgroups/blkio-controller.txt
@@ -134,6 +134,11 @@ Details of cgroup files
 	  minor number of the device, third field specifies the operation type
 	  and the fourth field specifies the io_wait_time in ns.
 
+- blkio.io_merged
+	- Total number of bios/requests merged into requests belonging to this
+	  cgroup. This is further divided by the type of operation - read or
+	  write, sync or async.
+
 - blkio.dequeue
 	- Debugging aid only enabled if CONFIG_DEBUG_CFQ_IOSCHED=y. This
 	  gives the statistics about how many a times a group was dequeued

diff --git a/trunk/block/blk-cgroup.c b/trunk/block/blk-cgroup.c
@@ -127,6 +127,18 @@ void blkiocg_update_completion_stats(struct blkio_group *blkg,
 }
 EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats);
 
+void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
+					bool sync)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&blkg->stats_lock, flags);
+	blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_MERGED], 1, direction,
+			sync);
+	spin_unlock_irqrestore(&blkg->stats_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats);
+
 void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
 			struct blkio_group *blkg, void *key, dev_t dev)
 {
@@ -363,6 +375,7 @@ SHOW_FUNCTION_PER_GROUP(io_service_bytes, BLKIO_STAT_SERVICE_BYTES, 1);
 SHOW_FUNCTION_PER_GROUP(io_serviced, BLKIO_STAT_SERVICED, 1);
 SHOW_FUNCTION_PER_GROUP(io_service_time, BLKIO_STAT_SERVICE_TIME, 1);
 SHOW_FUNCTION_PER_GROUP(io_wait_time, BLKIO_STAT_WAIT_TIME, 1);
+SHOW_FUNCTION_PER_GROUP(io_merged, BLKIO_STAT_MERGED, 1);
 #ifdef CONFIG_DEBUG_BLK_CGROUP
 SHOW_FUNCTION_PER_GROUP(dequeue, BLKIO_STAT_DEQUEUE, 0);
 #endif
@@ -407,6 +420,10 @@ struct cftype blkio_files[] = {
 		.name = "io_wait_time",
 		.read_map = blkiocg_io_wait_time_read,
 	},
+	{
+		.name = "io_merged",
+		.read_map = blkiocg_io_merged_read,
+	},
 	{
 		.name = "reset_stats",
 		.write_u64 = blkiocg_reset_stats,

diff --git a/trunk/block/blk-cgroup.h b/trunk/block/blk-cgroup.h
@@ -34,6 +34,8 @@ enum stat_type {
 	BLKIO_STAT_SERVICED,
 	/* Total time spent waiting in scheduler queue in ns */
 	BLKIO_STAT_WAIT_TIME,
+	/* Number of IOs merged */
+	BLKIO_STAT_MERGED,
 	/* All the single valued stats go below this */
 	BLKIO_STAT_TIME,
 	BLKIO_STAT_SECTORS,
@@ -61,7 +63,7 @@ struct blkio_group_stats {
 	/* total disk time and nr sectors dispatched by this group */
 	uint64_t time;
 	uint64_t sectors;
-	uint64_t stat_arr[BLKIO_STAT_WAIT_TIME + 1][BLKIO_STAT_TOTAL];
+	uint64_t stat_arr[BLKIO_STAT_MERGED + 1][BLKIO_STAT_TOTAL];
 #ifdef CONFIG_DEBUG_BLK_CGROUP
 	/* How many times this group has been removed from service tree */
 	unsigned long dequeue;
@@ -148,6 +150,8 @@ void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
 						bool direction, bool sync);
 void blkiocg_update_completion_stats(struct blkio_group *blkg,
 	uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
+void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
+					bool sync);
 #else
 struct cgroup;
 static inline struct blkio_cgroup *
@@ -169,5 +173,7 @@ static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
 static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
 		uint64_t start_time, uint64_t io_start_time, bool direction,
 		bool sync) {}
+static inline void blkiocg_update_io_merged_stats(struct blkio_group *blkg,
+						bool direction, bool sync) {}
 #endif
 #endif /* _BLK_CGROUP_H */
diff --git a/trunk/block/blk-core.c b/trunk/block/blk-core.c
@@ -1202,6 +1202,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 		if (!blk_rq_cpu_valid(req))
 			req->cpu = bio->bi_comp_cpu;
 		drive_stat_acct(req, 0);
+		elv_bio_merged(q, req, bio);
 		if (!attempt_back_merge(q, req))
 			elv_merged_request(q, req, el_ret);
 		goto out;
@@ -1235,6 +1236,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 		if (!blk_rq_cpu_valid(req))
 			req->cpu = bio->bi_comp_cpu;
 		drive_stat_acct(req, 0);
+		elv_bio_merged(q, req, bio);
 		if (!attempt_front_merge(q, req))
 			elv_merged_request(q, req, el_ret);
 		goto out;

diff --git a/trunk/block/cfq-iosched.c b/trunk/block/cfq-iosched.c
@@ -1467,6 +1467,14 @@ static void cfq_merged_request(struct request_queue *q, struct request *req,
 	}
 }
 
+static void cfq_bio_merged(struct request_queue *q, struct request *req,
+				struct bio *bio)
+{
+	struct cfq_queue *cfqq = RQ_CFQQ(req);
+	blkiocg_update_io_merged_stats(&cfqq->cfqg->blkg, bio_data_dir(bio),
+					cfq_bio_sync(bio));
+}
+
 static void
 cfq_merged_requests(struct request_queue *q, struct request *rq,
 		    struct request *next)
@@ -1484,6 +1492,8 @@ cfq_merged_requests(struct request_queue *q, struct request *rq,
 	if (cfqq->next_rq == next)
 		cfqq->next_rq = rq;
 	cfq_remove_request(next);
+	blkiocg_update_io_merged_stats(&cfqq->cfqg->blkg, rq_data_dir(next),
+					rq_is_sync(next));
 }
 
 static int cfq_allow_merge(struct request_queue *q, struct request *rq,
@@ -3861,6 +3871,7 @@ static struct elevator_type iosched_cfq = {
 		.elevator_merged_fn =		cfq_merged_request,
 		.elevator_merge_req_fn =	cfq_merged_requests,
 		.elevator_allow_merge_fn =	cfq_allow_merge,
+		.elevator_bio_merged_fn =	cfq_bio_merged,
 		.elevator_dispatch_fn =		cfq_dispatch_requests,
 		.elevator_add_req_fn =		cfq_insert_request,
 		.elevator_activate_req_fn =	cfq_activate_request,

diff --git a/trunk/block/elevator.c b/trunk/block/elevator.c
@@ -539,6 +539,15 @@ void elv_merge_requests(struct request_queue *q, struct request *rq,
 	q->last_merge = rq;
 }
 
+void elv_bio_merged(struct request_queue *q, struct request *rq,
+			struct bio *bio)
+{
+	struct elevator_queue *e = q->elevator;
+
+	if (e->ops->elevator_bio_merged_fn)
+		e->ops->elevator_bio_merged_fn(q, rq, bio);
+}
+
 void elv_requeue_request(struct request_queue *q, struct request *rq)
 {
 	/*

diff --git a/trunk/include/linux/elevator.h b/trunk/include/linux/elevator.h
@@ -14,6 +14,9 @@ typedef void (elevator_merged_fn) (struct request_queue *, struct request *, int
 
 typedef int (elevator_allow_merge_fn) (struct request_queue *, struct request *, struct bio *);
 
+typedef void (elevator_bio_merged_fn) (struct request_queue *,
+						struct request *, struct bio *);
+
 typedef int (elevator_dispatch_fn) (struct request_queue *, int);
 
 typedef void (elevator_add_req_fn) (struct request_queue *, struct request *);
@@ -36,6 +39,7 @@ struct elevator_ops
 	elevator_merged_fn *elevator_merged_fn;
 	elevator_merge_req_fn *elevator_merge_req_fn;
 	elevator_allow_merge_fn *elevator_allow_merge_fn;
+	elevator_bio_merged_fn *elevator_bio_merged_fn;
 
 	elevator_dispatch_fn *elevator_dispatch_fn;
 	elevator_add_req_fn *elevator_add_req_fn;
@@ -103,6 +107,8 @@ extern int elv_merge(struct request_queue *, struct request **, struct bio *);
 extern void elv_merge_requests(struct request_queue *, struct request *,
 			       struct request *);
 extern void elv_merged_request(struct request_queue *, struct request *, int);
+extern void elv_bio_merged(struct request_queue *q, struct request *,
+				struct bio *);
 extern void elv_requeue_request(struct request_queue *, struct request *);
 extern int elv_queue_empty(struct request_queue *);
 extern struct request *elv_former_request(struct request_queue *, struct request *);