diff options
| -rw-r--r-- | drivers/block/xen-blkback/blkback.c | 22 | ||||
| -rw-r--r-- | drivers/block/xen-blkback/xenbus.c | 5 |
2 files changed, 19 insertions, 8 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index a295ad6a1674..8dbdd156e0d3 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -173,7 +173,7 @@ static inline void shrink_free_pagepool(struct xen_blkif *blkif, int num) #define vaddr(page) ((unsigned long)pfn_to_kaddr(page_to_pfn(page))) -static int do_block_io_op(struct xen_blkif *blkif); +static int do_block_io_op(struct xen_blkif *blkif, unsigned int *eoi_flags); static int dispatch_rw_block_io(struct xen_blkif *blkif, struct blkif_request *req, struct pending_req *pending_req); @@ -594,6 +594,8 @@ int xen_blkif_schedule(void *arg) struct xen_vbd *vbd = &blkif->vbd; unsigned long timeout; int ret; + bool do_eoi; + unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS; while (!kthread_should_stop()) { if (try_to_freeze()) @@ -617,16 +619,23 @@ int xen_blkif_schedule(void *arg) if (timeout == 0) goto purge_gnt_list; + do_eoi = blkif->waiting_reqs; + blkif->waiting_reqs = 0; smp_mb(); /* clear flag *before* checking for work */ - ret = do_block_io_op(blkif); + ret = do_block_io_op(blkif, &eoi_flags); if (ret > 0) blkif->waiting_reqs = 1; if (ret == -EACCES) wait_event_interruptible(blkif->shutdown_wq, kthread_should_stop()); + if (do_eoi && !blkif->waiting_reqs) { + xen_irq_lateeoi(blkif->irq, eoi_flags); + eoi_flags |= XEN_EOI_FLAG_SPURIOUS; + } + purge_gnt_list: if (blkif->vbd.feature_gnt_persistent && time_after(jiffies, blkif->next_lru)) { @@ -1094,7 +1103,7 @@ static void end_block_io_op(struct bio *bio) * 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) +__do_block_io_op(struct xen_blkif *blkif, unsigned int *eoi_flags) { union blkif_back_rings *blk_rings = &blkif->blk_rings; struct blkif_request req; @@ -1117,6 +1126,9 @@ __do_block_io_op(struct xen_blkif *blkif) if (RING_REQUEST_CONS_OVERFLOW(&blk_rings->common, rc)) break; + /* We've seen a request, so clear spurious eoi flag. */ + *eoi_flags &= ~XEN_EOI_FLAG_SPURIOUS; + if (kthread_should_stop()) { more_to_do = 1; break; @@ -1175,13 +1187,13 @@ done: } static int -do_block_io_op(struct xen_blkif *blkif) +do_block_io_op(struct xen_blkif *blkif, unsigned int *eoi_flags) { union blkif_back_rings *blk_rings = &blkif->blk_rings; int more_to_do; do { - more_to_do = __do_block_io_op(blkif); + more_to_do = __do_block_io_op(blkif, eoi_flags); if (more_to_do) break; diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 923308201375..0ec257e69e95 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -200,9 +200,8 @@ static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t *gref, BUG(); } - err = bind_interdomain_evtchn_to_irqhandler(blkif->domid, evtchn, - xen_blkif_be_int, 0, - "blkif-backend", blkif); + err = bind_interdomain_evtchn_to_irqhandler_lateeoi(blkif->domid, + evtchn, xen_blkif_be_int, 0, "blkif-backend", blkif); if (err < 0) { xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring); blkif->blk_rings.common.sring = NULL; |