Date: Thu, 15 Mar 2018 10:52:08 +0000 (UTC) From: Andriy Gapon <avg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r330986 - in stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs: . sys Message-ID: <201803151052.w2FAq8DU005391@repo.freebsd.org>
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Author: avg Date: Thu Mar 15 10:52:08 2018 New Revision: 330986 URL: https://svnweb.freebsd.org/changeset/base/330986 Log: MFC r329717: MFV r329715: 8997 ztest assertion failure in zil_lwb_write_issue Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_tx.h stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c Thu Mar 15 10:13:25 2018 (r330985) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c Thu Mar 15 10:52:08 2018 (r330986) @@ -858,7 +858,7 @@ dmu_tx_delay(dmu_tx_t *tx, uint64_t dirty) * decreasing performance. */ static int -dmu_tx_try_assign(dmu_tx_t *tx, txg_how_t txg_how) +dmu_tx_try_assign(dmu_tx_t *tx, uint64_t txg_how) { spa_t *spa = tx->tx_pool->dp_spa; @@ -878,13 +878,13 @@ dmu_tx_try_assign(dmu_tx_t *tx, txg_how_t txg_how) * of the failuremode setting. */ if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE && - txg_how != TXG_WAIT) + !(txg_how & TXG_WAIT)) return (SET_ERROR(EIO)); return (SET_ERROR(ERESTART)); } - if (!tx->tx_waited && + if (!tx->tx_dirty_delayed && dsl_pool_need_dirty_delay(tx->tx_pool)) { tx->tx_wait_dirty = B_TRUE; return (SET_ERROR(ERESTART)); @@ -972,41 +972,44 @@ dmu_tx_unassign(dmu_tx_t *tx) } /* - * Assign tx to a transaction group. txg_how can be one of: + * Assign tx to a transaction group; txg_how is a bitmask: * - * (1) TXG_WAIT. If the current open txg is full, waits until there's - * a new one. This should be used when you're not holding locks. - * It will only fail if we're truly out of space (or over quota). + * If TXG_WAIT is set and the currently open txg is full, this function + * will wait until there's a new txg. This should be used when no locks + * are being held. With this bit set, this function will only fail if + * we're truly out of space (or over quota). * - * (2) TXG_NOWAIT. If we can't assign into the current open txg without - * blocking, returns immediately with ERESTART. This should be used - * whenever you're holding locks. On an ERESTART error, the caller - * should drop locks, do a dmu_tx_wait(tx), and try again. + * If TXG_WAIT is *not* set and we can't assign into the currently open + * txg without blocking, this function will return immediately with + * ERESTART. This should be used whenever locks are being held. On an + * ERESTART error, the caller should drop all locks, call dmu_tx_wait(), + * and try again. * - * (3) TXG_WAITED. Like TXG_NOWAIT, but indicates that dmu_tx_wait() - * has already been called on behalf of this operation (though - * most likely on a different tx). + * If TXG_NOTHROTTLE is set, this indicates that this tx should not be + * delayed due on the ZFS Write Throttle (see comments in dsl_pool.c for + * details on the throttle). This is used by the VFS operations, after + * they have already called dmu_tx_wait() (though most likely on a + * different tx). */ int -dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how) +dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how) { int err; ASSERT(tx->tx_txg == 0); - ASSERT(txg_how == TXG_WAIT || txg_how == TXG_NOWAIT || - txg_how == TXG_WAITED); + ASSERT0(txg_how & ~(TXG_WAIT | TXG_NOTHROTTLE)); ASSERT(!dsl_pool_sync_context(tx->tx_pool)); /* If we might wait, we must not hold the config lock. */ - ASSERT(txg_how != TXG_WAIT || !dsl_pool_config_held(tx->tx_pool)); + IMPLY((txg_how & TXG_WAIT), !dsl_pool_config_held(tx->tx_pool)); - if (txg_how == TXG_WAITED) - tx->tx_waited = B_TRUE; + if ((txg_how & TXG_NOTHROTTLE)) + tx->tx_dirty_delayed = B_TRUE; while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) { dmu_tx_unassign(tx); - if (err != ERESTART || txg_how != TXG_WAIT) + if (err != ERESTART || !(txg_how & TXG_WAIT)) return (err); dmu_tx_wait(tx); @@ -1043,12 +1046,12 @@ dmu_tx_wait(dmu_tx_t *tx) tx->tx_wait_dirty = B_FALSE; /* - * Note: setting tx_waited only has effect if the caller - * used TX_WAIT. Otherwise they are going to destroy - * this tx and try again. The common case, zfs_write(), - * uses TX_WAIT. + * Note: setting tx_dirty_delayed only has effect if the + * caller used TX_WAIT. Otherwise they are going to + * destroy this tx and try again. The common case, + * zfs_write(), uses TX_WAIT. */ - tx->tx_waited = B_TRUE; + tx->tx_dirty_delayed = B_TRUE; } else if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { /* * If the pool is suspended we need to wait until it Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h Thu Mar 15 10:13:25 2018 (r330985) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h Thu Mar 15 10:52:08 2018 (r330986) @@ -231,11 +231,14 @@ typedef enum dmu_object_type { DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE), } dmu_object_type_t; -typedef enum txg_how { - TXG_WAIT = 1, - TXG_NOWAIT, - TXG_WAITED, -} txg_how_t; +/* + * These flags are intended to be used to specify the "txg_how" + * parameter when calling the dmu_tx_assign() function. See the comment + * above dmu_tx_assign() for more details on the meaning of these flags. + */ +#define TXG_NOWAIT (0ULL) +#define TXG_WAIT (1ULL<<0) +#define TXG_NOTHROTTLE (1ULL<<1) void byteswap_uint64_array(void *buf, size_t size); void byteswap_uint32_array(void *buf, size_t size); @@ -684,7 +687,7 @@ void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object); void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow); void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size); void dmu_tx_abort(dmu_tx_t *tx); -int dmu_tx_assign(dmu_tx_t *tx, enum txg_how txg_how); +int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); void dmu_tx_wait(dmu_tx_t *tx); void dmu_tx_commit(dmu_tx_t *tx); void dmu_tx_mark_netfree(dmu_tx_t *tx); Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_tx.h ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_tx.h Thu Mar 15 10:13:25 2018 (r330985) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_tx.h Thu Mar 15 10:52:08 2018 (r330986) @@ -66,9 +66,6 @@ struct dmu_tx { /* placeholder for syncing context, doesn't need specific holds */ boolean_t tx_anyobj; - /* has this transaction already been delayed? */ - boolean_t tx_waited; - /* transaction is marked as being a "net free" of space */ boolean_t tx_netfree; @@ -78,6 +75,9 @@ struct dmu_tx { /* need to wait for sufficient dirty space */ boolean_t tx_wait_dirty; + /* has this transaction already been delayed? */ + boolean_t tx_dirty_delayed; + int tx_err; }; @@ -113,7 +113,7 @@ typedef struct dmu_tx_callback { * These routines are defined in dmu.h, and are called by the user. */ dmu_tx_t *dmu_tx_create(objset_t *dd); -int dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how); +int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how); void dmu_tx_commit(dmu_tx_t *tx); void dmu_tx_abort(dmu_tx_t *tx); uint64_t dmu_tx_get_txg(dmu_tx_t *tx); Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c Thu Mar 15 10:13:25 2018 (r330985) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c Thu Mar 15 10:52:08 2018 (r330986) @@ -127,7 +127,7 @@ * * If dmu_tx_assign() returns ERESTART and zfsvfs->z_assign is TXG_NOWAIT, * then drop all locks, call dmu_tx_wait(), and try again. On subsequent - * calls to dmu_tx_assign(), pass TXG_WAITED rather than TXG_NOWAIT, + * calls to dmu_tx_assign(), pass TXG_NOTHROTTLE in addition to TXG_NOWAIT, * to indicate that this operation has already called dmu_tx_wait(). * This will ensure that we don't retry forever, waiting a short bit * each time. @@ -152,7 +152,7 @@ * rw_enter(...); // grab any other locks you need * tx = dmu_tx_create(...); // get DMU tx * dmu_tx_hold_*(); // hold each object you might modify - * error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); + * error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT); * if (error) { * rw_exit(...); // drop locks * zfs_dirent_unlock(dl); // unlock directory entry Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c Thu Mar 15 10:13:25 2018 (r330985) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zil.c Thu Mar 15 10:52:08 2018 (r330986) @@ -1217,22 +1217,13 @@ zil_lwb_write_issue(zilog_t *zilog, lwb_t *lwb) tx = dmu_tx_create(zilog->zl_os); /* - * Since we are not going to create any new dirty data and we can even - * help with clearing the existing dirty data, we should not be subject - * to the dirty data based delays. - * We (ab)use TXG_WAITED to bypass the delay mechanism. - * One side effect from using TXG_WAITED is that dmu_tx_assign() can - * fail if the pool is suspended. Those are dramatic circumstances, - * so we return NULL to signal that the normal ZIL processing is not - * possible and txg_wait_synced() should be used to ensure that the data - * is on disk. + * Since we are not going to create any new dirty data, and we + * can even help with clearing the existing dirty data, we + * should not be subject to the dirty data based delays. We + * use TXG_NOTHROTTLE to bypass the delay mechanism. */ - error = dmu_tx_assign(tx, TXG_WAITED); - if (error != 0) { - ASSERT3S(error, ==, EIO); - dmu_tx_abort(tx); - return (NULL); - } + VERIFY0(dmu_tx_assign(tx, TXG_WAIT | TXG_NOTHROTTLE)); + dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); txg = dmu_tx_get_txg(tx);
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