diff options
Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 37 |
1 files changed, 20 insertions, 17 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 5cf2993a8338..2330a9ad5e95 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -458,7 +458,8 @@ static void end_block_io_op(struct bio *bio, int error) * (which has the sectors we want, number of them, grant references, etc), * and transmute it to the block API to hand it over to the proper block disk. */ -static int do_block_io_op(struct xen_blkif *blkif) +static int +__do_block_io_op(struct xen_blkif *blkif) { union blkif_back_rings *blk_rings = &blkif->blk_rings; struct blkif_request req; @@ -515,6 +516,23 @@ static int do_block_io_op(struct xen_blkif *blkif) return more_to_do; } +static int +do_block_io_op(struct xen_blkif *blkif) +{ + union blkif_back_rings *blk_rings = &blkif->blk_rings; + int more_to_do; + + do { + more_to_do = __do_block_io_op(blkif); + if (more_to_do) + break; + + RING_FINAL_CHECK_FOR_REQUESTS(&blk_rings->common, more_to_do); + } while (more_to_do); + + return more_to_do; +} + /* * Transmutation of the 'struct blkif_request' to a proper 'struct bio' * and call the 'submit_bio' to pass it to the underlying storage. @@ -700,7 +718,6 @@ static void make_response(struct xen_blkif *blkif, u64 id, struct blkif_response resp; unsigned long flags; union blkif_back_rings *blk_rings = &blkif->blk_rings; - int more_to_do = 0; int notify; resp.id = id; @@ -727,22 +744,7 @@ static void make_response(struct xen_blkif *blkif, u64 id, } blk_rings->common.rsp_prod_pvt++; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blk_rings->common, notify); - if (blk_rings->common.rsp_prod_pvt == blk_rings->common.req_cons) { - /* - * Tail check for pending requests. Allows frontend to avoid - * notifications if requests are already in flight (lower - * overheads and promotes batching). - */ - RING_FINAL_CHECK_FOR_REQUESTS(&blk_rings->common, more_to_do); - - } else if (RING_HAS_UNCONSUMED_REQUESTS(&blk_rings->common)) { - more_to_do = 1; - } - spin_unlock_irqrestore(&blkif->blk_ring_lock, flags); - - if (more_to_do) - blkif_notify_work(blkif); if (notify) notify_remote_via_irq(blkif->irq); } @@ -824,3 +826,4 @@ static int __init xen_blkif_init(void) module_init(xen_blkif_init); MODULE_LICENSE("Dual BSD/GPL"); +MODULE_ALIAS("xen-backend:vbd"); |