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author | delphij <delphij@FreeBSD.org> | 2013-08-24 00:42:37 +0000 |
---|---|---|
committer | delphij <delphij@FreeBSD.org> | 2013-08-24 00:42:37 +0000 |
commit | a6fe3ad03c345a602a25a8688c5e894754484f2c (patch) | |
tree | 827c930d1ac70047bb1fdac7a872343f1c63174d | |
parent | b1dbe0883f220b97df777f74753476e0328015c7 (diff) | |
download | FreeBSD-src-a6fe3ad03c345a602a25a8688c5e894754484f2c.zip FreeBSD-src-a6fe3ad03c345a602a25a8688c5e894754484f2c.tar.gz |
MFV r254749:
Don't hold dd_lock for long by breaking it when not doing dsl_dir
accounting. It is not necessary to hold the lock while manipulating
the parent's accounting, because there is no interface for userland
to see a consistent picture of both parent and child at the same
time anyway.
Illumos ZFS issues:
4046 dsl_dataset_t ds_dir->dd_lock is highly contended
-rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c | 31 | ||||
-rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c | 21 |
2 files changed, 14 insertions, 38 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c index ff6e682..1b69ed52 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c @@ -101,9 +101,8 @@ dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) used, compressed, uncompressed); return; } - dmu_buf_will_dirty(ds->ds_dbuf, tx); - mutex_enter(&ds->ds_dir->dd_lock); + dmu_buf_will_dirty(ds->ds_dbuf, tx); mutex_enter(&ds->ds_lock); delta = parent_delta(ds, used); ds->ds_phys->ds_referenced_bytes += used; @@ -115,7 +114,6 @@ dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx) compressed, uncompressed, tx); dsl_dir_transfer_space(ds->ds_dir, used - delta, DD_USED_REFRSRV, DD_USED_HEAD, tx); - mutex_exit(&ds->ds_dir->dd_lock); } int @@ -150,7 +148,6 @@ dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, dprintf_bp(bp, "freeing ds=%llu", ds->ds_object); dsl_free(tx->tx_pool, tx->tx_txg, bp); - mutex_enter(&ds->ds_dir->dd_lock); mutex_enter(&ds->ds_lock); ASSERT(ds->ds_phys->ds_unique_bytes >= used || !DS_UNIQUE_IS_ACCURATE(ds)); @@ -161,7 +158,6 @@ dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx, delta, -compressed, -uncompressed, tx); dsl_dir_transfer_space(ds->ds_dir, -used - delta, DD_USED_REFRSRV, DD_USED_HEAD, tx); - mutex_exit(&ds->ds_dir->dd_lock); } else { dprintf_bp(bp, "putting on dead list: %s", ""); if (async) { @@ -596,31 +592,6 @@ dsl_dataset_name(dsl_dataset_t *ds, char *name) } } -static int -dsl_dataset_namelen(dsl_dataset_t *ds) -{ - int result; - - if (ds == NULL) { - result = 3; /* "mos" */ - } else { - result = dsl_dir_namelen(ds->ds_dir); - VERIFY0(dsl_dataset_get_snapname(ds)); - if (ds->ds_snapname[0]) { - ++result; /* adding one for the @-sign */ - if (!MUTEX_HELD(&ds->ds_lock)) { - mutex_enter(&ds->ds_lock); - result += strlen(ds->ds_snapname); - mutex_exit(&ds->ds_lock); - } else { - result += strlen(ds->ds_snapname); - } - } - } - - return (result); -} - void dsl_dataset_rele(dsl_dataset_t *ds, void *tag) { diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c index 7d0b104..4c86f9c 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c @@ -845,11 +845,21 @@ dsl_dir_diduse_space(dsl_dir_t *dd, dd_used_t type, int64_t used, int64_t compressed, int64_t uncompressed, dmu_tx_t *tx) { int64_t accounted_delta; + + /* + * dsl_dataset_set_refreservation_sync_impl() calls this with + * dd_lock held, so that it can atomically update + * ds->ds_reserved and the dsl_dir accounting, so that + * dsl_dataset_check_quota() can see dataset and dir accounting + * consistently. + */ boolean_t needlock = !MUTEX_HELD(&dd->dd_lock); ASSERT(dmu_tx_is_syncing(tx)); ASSERT(type < DD_USED_NUM); + dmu_buf_will_dirty(dd->dd_dbuf, tx); + if (needlock) mutex_enter(&dd->dd_lock); accounted_delta = parent_delta(dd, dd->dd_phys->dd_used_bytes, used); @@ -858,7 +868,6 @@ dsl_dir_diduse_space(dsl_dir_t *dd, dd_used_t type, dd->dd_phys->dd_compressed_bytes >= -compressed); ASSERT(uncompressed >= 0 || dd->dd_phys->dd_uncompressed_bytes >= -uncompressed); - dmu_buf_will_dirty(dd->dd_dbuf, tx); dd->dd_phys->dd_used_bytes += used; dd->dd_phys->dd_uncompressed_bytes += uncompressed; dd->dd_phys->dd_compressed_bytes += compressed; @@ -891,8 +900,6 @@ void dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta, dd_used_t oldtype, dd_used_t newtype, dmu_tx_t *tx) { - boolean_t needlock = !MUTEX_HELD(&dd->dd_lock); - ASSERT(dmu_tx_is_syncing(tx)); ASSERT(oldtype < DD_USED_NUM); ASSERT(newtype < DD_USED_NUM); @@ -900,17 +907,15 @@ dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta, if (delta == 0 || !(dd->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN)) return; - if (needlock) - mutex_enter(&dd->dd_lock); + dmu_buf_will_dirty(dd->dd_dbuf, tx); + mutex_enter(&dd->dd_lock); ASSERT(delta > 0 ? dd->dd_phys->dd_used_breakdown[oldtype] >= delta : dd->dd_phys->dd_used_breakdown[newtype] >= -delta); ASSERT(dd->dd_phys->dd_used_bytes >= ABS(delta)); - dmu_buf_will_dirty(dd->dd_dbuf, tx); dd->dd_phys->dd_used_breakdown[oldtype] -= delta; dd->dd_phys->dd_used_breakdown[newtype] += delta; - if (needlock) - mutex_exit(&dd->dd_lock); + mutex_exit(&dd->dd_lock); } typedef struct dsl_dir_set_qr_arg { |