This helper will be used to decide if this block device can be
put into runtime suspend.
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: "James E.J. Bottomley" <jejb@xxxxxxxxxxxxxxxxxx>
Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
Cc: linux-scsi@xxxxxxxxxxxxxxx
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-mq.c | 22 ++++++++++++++++++++++
block/blk-mq.h | 3 +++
2 files changed, 25 insertions(+)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 73a43b81b17d..3a78fed87959 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -58,6 +58,28 @@ static int blk_mq_poll_stats_bkt(const struct request *rq)
return bucket;
}
+static void blk_mq_pm_check_idle(struct blk_mq_hw_ctx *hctx,
+ struct request *rq, void *priv, bool reserved)
+{
+ unsigned long *cnt = priv;
+
+ if (!(rq->rq_flags & RQF_PM))
+ (*cnt)++;
+}
+
+bool blk_mq_pm_queue_idle(struct request_queue *q)
+{
+ unsigned long idle_cnt;
+
+ if (!blk_mq_support_runtime_pm(q))
+ return false;
+
+ idle_cnt = 0;
+ blk_mq_queue_tag_busy_iter(q, blk_mq_pm_check_idle, &idle_cnt);
+
+ return idle_cnt == 0;
+}
+
/*
* Check if any of the ctx's have pending work in this hardware queue
*/
diff --git a/block/blk-mq.h b/block/blk-mq.h
index bc2b24735ed4..b64f6f69176a 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -88,6 +88,9 @@ extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
void blk_mq_release(struct request_queue *q);
+/* blk-mq pm helpers */
+bool blk_mq_pm_queue_idle(struct request_queue *q);
+
/**
* blk_mq_rq_state() - read the current MQ_RQ_* state of a request
* @rq: target request.
--
2.9.5
