diff options
| -rw-r--r-- | block/blk-mq.c | 7 | ||||
| -rw-r--r-- | include/linux/blk-mq.h | 1 |
2 files changed, 7 insertions, 1 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 7e5303820452..b355b5957cd7 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1172,7 +1172,12 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio) goto run_queue; } - if (is_sync) { + /* + * If the driver supports defer issued based on 'last', then + * queue it up like normal since we can potentially save some + * CPU this way. + */ + if (is_sync && !(data.hctx->flags & BLK_MQ_F_DEFER_ISSUE)) { struct blk_mq_queue_data bd = { .rq = rq, .list = NULL, diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index be01d7a687d4..c3b64ec5321e 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -146,6 +146,7 @@ enum { BLK_MQ_F_TAG_SHARED = 1 << 1, BLK_MQ_F_SG_MERGE = 1 << 2, BLK_MQ_F_SYSFS_UP = 1 << 3, + BLK_MQ_F_DEFER_ISSUE = 1 << 4, BLK_MQ_S_STOPPED = 0, BLK_MQ_S_TAG_ACTIVE = 1, |