diff --git a/include/sys/zio_impl.h b/include/sys/zio_impl.h index 787079d2c..08f820103 100644 --- a/include/sys/zio_impl.h +++ b/include/sys/zio_impl.h @@ -24,7 +24,7 @@ */ /* - * Copyright (c) 2012 by Delphix. All rights reserved. + * Copyright (c) 2013 by Delphix. All rights reserved. */ #ifndef _ZIO_IMPL_H @@ -38,7 +38,7 @@ extern "C" { #endif /* - * XXX -- Describe ZFS I/O pipleine here. Fill in as needed. + * XXX -- Describe ZFS I/O pipeline here. Fill in as needed. * * The ZFS I/O pipeline is comprised of various stages which are defined * in the zio_stage enum below. The individual stages are used to construct @@ -213,7 +213,6 @@ enum zio_stage { #define ZIO_FREE_PIPELINE \ (ZIO_INTERLOCK_STAGES | \ ZIO_STAGE_FREE_BP_INIT | \ - ZIO_STAGE_ISSUE_ASYNC | \ ZIO_STAGE_DVA_FREE) #define ZIO_DDT_FREE_PIPELINE \ diff --git a/module/zfs/zio.c b/module/zfs/zio.c index f0c9c0f08..0ef9f28b4 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -783,7 +783,20 @@ void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp) { metaslab_check_free(spa, bp); - bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp); + + /* + * Frees that are for the currently-syncing txg, are not going to be + * deferred, and which will not need to do a read (i.e. not GANG or + * DEDUP), can be processed immediately. Otherwise, put them on the + * in-memory list for later processing. + */ + if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp) || + txg != spa->spa_syncing_txg || + spa_sync_pass(spa) >= zfs_sync_pass_deferred_free) { + bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp); + } else { + VERIFY0(zio_wait(zio_free_sync(NULL, spa, txg, bp, 0))); + } } zio_t * @@ -791,6 +804,7 @@ zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, enum zio_flag flags) { zio_t *zio; + enum zio_stage stage = ZIO_FREE_PIPELINE; dprintf_bp(bp, "freeing in txg %llu, pass %u", (longlong_t)txg, spa->spa_sync_pass); @@ -802,9 +816,18 @@ zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, metaslab_check_free(spa, bp); arc_freed(spa, bp); + /* + * GANG and DEDUP blocks can induce a read (for the gang block header, + * or the DDT), so issue them asynchronously so that this thread is + * not tied up. + */ + if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp)) + stage |= ZIO_STAGE_ISSUE_ASYNC; + zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp), - NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_FREE, flags, - NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_FREE_PIPELINE); + NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_NOW, flags, + NULL, 0, NULL, ZIO_STAGE_OPEN, stage); + return (zio); }