diff --git a/block/blk-core.c b/block/blk-core.c index d2f8f4049abddbf76d3414cd85ef36d2d4027d07..a564852920626a7984935bbf21aba5c5722e3908 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1302,7 +1302,10 @@ static int __make_request(struct request_queue *q, struct bio *bio) plug->should_sort = 1; } list_add_tail(&req->queuelist, &plug->list); + plug->count++; drive_stat_acct(req, 1); + if (plug->count >= BLK_MAX_REQUEST_COUNT) + blk_flush_plug_list(plug, false); } else { spin_lock_irq(q->queue_lock); add_acct_request(q, req, where); @@ -2626,6 +2629,7 @@ void blk_start_plug(struct blk_plug *plug) INIT_LIST_HEAD(&plug->list); INIT_LIST_HEAD(&plug->cb_list); plug->should_sort = 0; + plug->count = 0; /* * If this is a nested plug, don't actually assign it. It will be @@ -2709,6 +2713,7 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) return; list_splice_init(&plug->list, &list); + plug->count = 0; if (plug->should_sort) { list_sort(NULL, &list, plug_rq_cmp); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 36f2e2b99ae3879bbc201ab3effd9cec7f0e2e21..92edb9601242d1c8252056d5820925fd2d2821f1 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -862,7 +862,10 @@ struct blk_plug { struct list_head list; struct list_head cb_list; unsigned int should_sort; + unsigned int count; }; +#define BLK_MAX_REQUEST_COUNT 16 + struct blk_plug_cb { struct list_head list; void (*callback)(struct blk_plug_cb *);