diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index c4bc85e69d33c48e316ca6bd2495439b4fcdd7ac..ed85ba94b2e0a85a5962d4621c2ef55b035e3562 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -276,6 +276,8 @@ int xen_blkif_schedule(void *arg) printk(KERN_DEBUG "%s: started\n", current->comm); while (!kthread_should_stop()) { + struct blk_plug plug; + if (try_to_freeze()) continue; if (unlikely(vbd->size != vbd_sz(vbd))) @@ -292,9 +294,13 @@ int xen_blkif_schedule(void *arg) blkif->waiting_reqs = 0; smp_mb(); /* clear flag *before* checking for work */ + blk_start_plug(&plug); + if (do_block_io_op(blkif)) blkif->waiting_reqs = 1; + blk_finish_plug(&plug); + if (log_stats && time_after(jiffies, blkif->st_print)) print_stats(blkif); } @@ -547,7 +553,6 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, struct bio *biolist[BLKIF_MAX_SEGMENTS_PER_REQUEST]; int i, nbio = 0; int operation; - struct blk_plug plug; switch (req->operation) { case BLKIF_OP_READ: @@ -660,15 +665,9 @@ static void dispatch_rw_block_io(struct blkif_st *blkif, */ atomic_set(&pending_req->pendcnt, nbio); - /* Get a reference count for the disk queue and start sending I/O */ - blk_start_plug(&plug); - for (i = 0; i < nbio; i++) submit_bio(operation, biolist[i]); - blk_finish_plug(&plug); - /* Let the I/Os go.. */ - if (operation == READ) blkif->st_rd_sect += preq.nr_sects; else if (operation == WRITE || operation == WRITE_BARRIER)