From 97d7228f427218cb701b4149c3f8f9d77e8c64e4 Mon Sep 17 00:00:00 2001 From: Alexander Motin Date: Mon, 8 Apr 2024 18:23:43 -0400 Subject: [PATCH] Remove db_state DB_NOFILL checks from syncing context Syncing context should not depend on current state of dbuf, which could already change several times in later transaction groups, but rely solely on dirty record for the transaction group being synced. Some of the checks seem already impossible, while instead of others I think we should better check for absence of data in the specific dirty record rather than DB_NOFILL. Reviewed-by: Robert Evans Reviewed-by: Brian Behlendorf Signed-off-by: Alexander Motin Sponsored by: iXsystems, Inc. Closes #16057 --- module/zfs/dbuf.c | 44 +++++++++++++++++++------------------------- 1 file changed, 19 insertions(+), 25 deletions(-) diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c index 42e5811c8..5d1887175 100644 --- a/module/zfs/dbuf.c +++ b/module/zfs/dbuf.c @@ -4550,11 +4550,10 @@ dbuf_sync_leaf(dbuf_dirty_record_t *dr, dmu_tx_t *tx) if (os->os_encrypted && dn->dn_object == DMU_META_DNODE_OBJECT) dbuf_prepare_encrypted_dnode_leaf(dr); - if (db->db_state != DB_NOFILL && + if (*datap != NULL && *datap == db->db_buf && dn->dn_object != DMU_META_DNODE_OBJECT && zfs_refcount_count(&db->db_holds) > 1 && - dr->dt.dl.dr_override_state != DR_OVERRIDDEN && - *datap == db->db_buf) { + dr->dt.dl.dr_override_state != DR_OVERRIDDEN) { /* * If this buffer is currently "in use" (i.e., there * are active holds and db_data still references it), @@ -4839,11 +4838,9 @@ dbuf_write_done(zio_t *zio, arc_buf_t *buf, void *vdb) if (db->db_level == 0) { ASSERT(db->db_blkid != DMU_BONUS_BLKID); ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN); - if (db->db_state != DB_NOFILL) { - if (dr->dt.dl.dr_data != NULL && - dr->dt.dl.dr_data != db->db_buf) { - arc_buf_destroy(dr->dt.dl.dr_data, db); - } + if (dr->dt.dl.dr_data != NULL && + dr->dt.dl.dr_data != db->db_buf) { + arc_buf_destroy(dr->dt.dl.dr_data, db); } } else { ASSERT(list_head(&dr->dt.di.dr_children) == NULL); @@ -5042,21 +5039,18 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx) os = dn->dn_objset; - if (db->db_state != DB_NOFILL) { - if (db->db_level > 0 || dn->dn_type == DMU_OT_DNODE) { - /* - * Private object buffers are released here rather - * than in dbuf_dirty() since they are only modified - * in the syncing context and we don't want the - * overhead of making multiple copies of the data. - */ - if (BP_IS_HOLE(db->db_blkptr)) { - arc_buf_thaw(data); - } else { - dbuf_release_bp(db); - } - dbuf_remap(dn, db, tx); - } + if (db->db_level > 0 || dn->dn_type == DMU_OT_DNODE) { + /* + * Private object buffers are released here rather than in + * dbuf_dirty() since they are only modified in the syncing + * context and we don't want the overhead of making multiple + * copies of the data. + */ + if (BP_IS_HOLE(db->db_blkptr)) + arc_buf_thaw(data); + else + dbuf_release_bp(db); + dbuf_remap(dn, db, tx); } if (parent != dn->dn_dbuf) { @@ -5092,7 +5086,7 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx) if (db->db_blkid == DMU_SPILL_BLKID) wp_flag = WP_SPILL; - wp_flag |= (db->db_state == DB_NOFILL) ? WP_NOFILL : 0; + wp_flag |= (data == NULL) ? WP_NOFILL : 0; dmu_write_policy(os, dn, db->db_level, wp_flag, &zp); @@ -5124,7 +5118,7 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx) dr->dt.dl.dr_copies, dr->dt.dl.dr_nopwrite, dr->dt.dl.dr_brtwrite); mutex_exit(&db->db_mtx); - } else if (db->db_state == DB_NOFILL) { + } else if (data == NULL) { ASSERT(zp.zp_checksum == ZIO_CHECKSUM_OFF || zp.zp_checksum == ZIO_CHECKSUM_NOPARITY); dr->dr_zio = zio_write(pio, os->os_spa, txg,