svn commit: r280757 - in head/sys/geom: mirror raid

[Alexander Motin]

Author: mav
Date: Fri Mar 27 12:44:28 2015
New Revision: 280757
URL: https://svnweb.freebsd.org/changeset/base/280757

Log:
  Remove request sorting from GEOM_MIRROR and GEOM_RAID.
  
  When CPU is not busy, those queues are typically empty.  When CPU is busy,
  then one more extra sorting is the last thing it needs.  If specific device
  (HDD) really needs sorting, then it will be done later by CAM.
  
  This supposed to fix livelock reported for mirror of two SSDs, when UFS
  fires zillion of BIO_DELETE requests, that totally blocks I/O subsystem by
  pointless sorting of requests and responses under single mutex lock.
  
  MFC after:	2 weeks

Modified:
  head/sys/geom/mirror/g_mirror.c
  head/sys/geom/raid/g_raid.c

Modified: head/sys/geom/mirror/g_mirror.c
==============================================================================
--- head/sys/geom/mirror/g_mirror.c	Fri Mar 27 11:14:12 2015	(r280756)
+++ head/sys/geom/mirror/g_mirror.c	Fri Mar 27 12:44:28 2015	(r280757)
@@ -888,7 +888,7 @@ g_mirror_done(struct bio *bp)
 	sc = bp->bio_from->geom->softc;
 	bp->bio_cflags = G_MIRROR_BIO_FLAG_REGULAR;
 	mtx_lock(&sc->sc_queue_mtx);
-	bioq_disksort(&sc->sc_queue, bp);
+	bioq_insert_tail(&sc->sc_queue, bp);
 	mtx_unlock(&sc->sc_queue_mtx);
 	wakeup(sc);
 }
@@ -975,7 +975,7 @@ g_mirror_regular_request(struct bio *bp)
 		else {
 			pbp->bio_error = 0;
 			mtx_lock(&sc->sc_queue_mtx);
-			bioq_disksort(&sc->sc_queue, pbp);
+			bioq_insert_tail(&sc->sc_queue, pbp);
 			mtx_unlock(&sc->sc_queue_mtx);
 			G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
 			wakeup(sc);
@@ -1015,7 +1015,7 @@ g_mirror_sync_done(struct bio *bp)
 	sc = bp->bio_from->geom->softc;
 	bp->bio_cflags = G_MIRROR_BIO_FLAG_SYNC;
 	mtx_lock(&sc->sc_queue_mtx);
-	bioq_disksort(&sc->sc_queue, bp);
+	bioq_insert_tail(&sc->sc_queue, bp);
 	mtx_unlock(&sc->sc_queue_mtx);
 	wakeup(sc);
 }
@@ -1144,7 +1144,7 @@ g_mirror_start(struct bio *bp)
 		return;
 	}
 	mtx_lock(&sc->sc_queue_mtx);
-	bioq_disksort(&sc->sc_queue, bp);
+	bioq_insert_tail(&sc->sc_queue, bp);
 	mtx_unlock(&sc->sc_queue_mtx);
 	G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
 	wakeup(sc);

Modified: head/sys/geom/raid/g_raid.c
==============================================================================
--- head/sys/geom/raid/g_raid.c	Fri Mar 27 11:14:12 2015	(r280756)
+++ head/sys/geom/raid/g_raid.c	Fri Mar 27 12:44:28 2015	(r280757)
@@ -1132,7 +1132,7 @@ g_raid_start(struct bio *bp)
 		return;
 	}
 	mtx_lock(&sc->sc_queue_mtx);
-	bioq_disksort(&sc->sc_queue, bp);
+	bioq_insert_tail(&sc->sc_queue, bp);
 	mtx_unlock(&sc->sc_queue_mtx);
 	if (!dumping) {
 		G_RAID_DEBUG1(4, sc, "Waking up %p.", sc);
@@ -1344,7 +1344,7 @@ g_raid_unlock_range(struct g_raid_volume
 			    (intmax_t)(lp->l_offset+lp->l_length));
 			mtx_lock(&sc->sc_queue_mtx);
 			while ((bp = bioq_takefirst(&vol->v_locked)) != NULL)
-				bioq_disksort(&sc->sc_queue, bp);
+				bioq_insert_tail(&sc->sc_queue, bp);
 			mtx_unlock(&sc->sc_queue_mtx);
 			free(lp, M_RAID);
 			return (0);
@@ -1438,7 +1438,7 @@ g_raid_disk_done(struct bio *bp)
 	sd = bp->bio_caller1;
 	sc = sd->sd_softc;
 	mtx_lock(&sc->sc_queue_mtx);
-	bioq_disksort(&sc->sc_queue, bp);
+	bioq_insert_tail(&sc->sc_queue, bp);
 	mtx_unlock(&sc->sc_queue_mtx);
 	if (!dumping)
 		wakeup(sc);