From e879389f5777de5d94f27f8d88d7e92341afa3ef Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Fri, 12 Apr 2024 15:54:33 -0400 Subject: [PATCH] bcachefs: Fix bch2_btree_node_fill() for !path We shouldn't be doing the unlock/relock dance when we're not using a path - this fixes an assertion pop when called from btree node scan. Signed-off-by: Kent Overstreet --- fs/bcachefs/btree_cache.c | 46 ++++++++++++++++----------------------- 1 file changed, 19 insertions(+), 27 deletions(-) diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c index c347d08d80bc..02c70e813fac 100644 --- a/fs/bcachefs/btree_cache.c +++ b/fs/bcachefs/btree_cache.c @@ -709,7 +709,6 @@ static noinline struct btree *bch2_btree_node_fill(struct btree_trans *trans, struct bch_fs *c = trans->c; struct btree_cache *bc = &c->btree_cache; struct btree *b; - u32 seq; if (unlikely(level >= BTREE_MAX_DEPTH)) { int ret = bch2_fs_topology_error(c, "attempting to get btree node at level %u, >= max depth %u", @@ -775,34 +774,26 @@ static noinline struct btree *bch2_btree_node_fill(struct btree_trans *trans, } set_btree_node_read_in_flight(b); - six_unlock_write(&b->c.lock); - seq = six_lock_seq(&b->c.lock); - six_unlock_intent(&b->c.lock); - - /* Unlock before doing IO: */ - if (path && sync) - bch2_trans_unlock_noassert(trans); - - bch2_btree_node_read(trans, b, sync); - - if (!sync) - return NULL; if (path) { - int ret = bch2_trans_relock(trans) ?: - bch2_btree_path_relock_intent(trans, path); - if (ret) { - BUG_ON(!trans->restarted); - return ERR_PTR(ret); - } - } + u32 seq = six_lock_seq(&b->c.lock); - if (!six_relock_type(&b->c.lock, lock_type, seq)) { - BUG_ON(!path); + /* Unlock before doing IO: */ + six_unlock_intent(&b->c.lock); + bch2_trans_unlock_noassert(trans); - trace_and_count(c, trans_restart_relock_after_fill, trans, _THIS_IP_, path); - return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_relock_after_fill)); + bch2_btree_node_read(trans, b, sync); + + if (!sync) + return NULL; + + if (!six_relock_type(&b->c.lock, lock_type, seq)) + b = NULL; + } else { + bch2_btree_node_read(trans, b, sync); + if (lock_type == SIX_LOCK_read) + six_lock_downgrade(&b->c.lock); } return b; @@ -1135,18 +1126,19 @@ int bch2_btree_node_prefetch(struct btree_trans *trans, { struct bch_fs *c = trans->c; struct btree_cache *bc = &c->btree_cache; - struct btree *b; BUG_ON(path && !btree_node_locked(path, level + 1)); BUG_ON(level >= BTREE_MAX_DEPTH); - b = btree_cache_find(bc, k); + struct btree *b = btree_cache_find(bc, k); if (b) return 0; b = bch2_btree_node_fill(trans, path, k, btree_id, level, SIX_LOCK_read, false); - return PTR_ERR_OR_ZERO(b); + if (!IS_ERR_OR_NULL(b)) + six_unlock_read(&b->c.lock); + return bch2_trans_relock(trans) ?: PTR_ERR_OR_ZERO(b); } void bch2_btree_node_evict(struct btree_trans *trans, const struct bkey_i *k)