diff options
author | Kent Overstreet <kent.overstreet@linux.dev> | 2022-09-16 14:42:38 -0400 |
---|---|---|
committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-06-20 22:52:12 -0400 |
commit | c8e9bbf5b4d88c6582a0517303565e80d04fca6a (patch) | |
tree | 144fb1f34a6dd1c7d0571b999949a3a3107282c4 /fs/bcachefs/btree_update_interior.c | |
parent | 1a45519c8c484b40d81de88520dfd18c8c5f0870 (diff) |
bcachefs: All held locks must be in a btree path
With the new deadlock cycle detector, it's critical that all held locks
be marked in a btree_path, because that's what the cycle detector
traverses - any locks that aren't correctly marked will cause deadlocks.
This changes the btree_path to allocate some btree_paths for the new
nodes, since until the final update is done we otherwise don't have a
path referencing them.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'fs/bcachefs/btree_update_interior.c')
-rw-r--r-- | fs/bcachefs/btree_update_interior.c | 78 |
1 files changed, 75 insertions, 3 deletions
diff --git a/fs/bcachefs/btree_update_interior.c b/fs/bcachefs/btree_update_interior.c index 783b63bcce2f..7028597358d5 100644 --- a/fs/bcachefs/btree_update_interior.c +++ b/fs/bcachefs/btree_update_interior.c @@ -28,6 +28,22 @@ static void bch2_btree_insert_node(struct btree_update *, struct btree_trans *, struct keylist *, unsigned); static void bch2_btree_update_add_new_node(struct btree_update *, struct btree *); +static struct btree_path *get_unlocked_mut_path(struct btree_trans *trans, + enum btree_id btree_id, + unsigned level, + struct bpos pos) +{ + struct btree_path *path; + + path = bch2_path_get(trans, btree_id, pos, level + 1, level, + BTREE_ITER_NOPRESERVE| + BTREE_ITER_INTENT); + path = bch2_btree_path_make_mut(trans, path, true); + bch2_btree_path_downgrade(trans, path); + __bch2_btree_path_unlock(trans, path); + return path; +} + /* Debug code: */ /* @@ -618,7 +634,10 @@ static void btree_update_nodes_written(struct btree_update *as) "error %i in btree_update_nodes_written()", ret); err: if (as->b) { + struct btree_path *path; + b = as->b; + path = get_unlocked_mut_path(&trans, as->btree_id, b->c.level, b->key.k.p); /* * @b is the node we did the final insert into: * @@ -632,7 +651,12 @@ err: */ btree_node_lock_nopath_nofail(&trans, &b->c, SIX_LOCK_intent); - btree_node_lock_nopath_nofail(&trans, &b->c, SIX_LOCK_write); + mark_btree_node_locked(&trans, path, b->c.level, SIX_LOCK_intent); + path->l[b->c.level].lock_seq = b->c.lock.state.seq; + path->l[b->c.level].b = b; + + bch2_btree_node_lock_write_nofail(&trans, path, &b->c); + mutex_lock(&c->btree_interior_update_lock); list_del(&as->write_blocked_list); @@ -666,10 +690,13 @@ err: } mutex_unlock(&c->btree_interior_update_lock); + + mark_btree_node_locked_noreset(path, b->c.level, SIX_LOCK_intent); six_unlock_write(&b->c.lock); btree_node_write_if_need(c, b, SIX_LOCK_intent); - six_unlock_intent(&b->c.lock); + btree_node_unlock(&trans, path, b->c.level); + bch2_path_put(&trans, path, true); } bch2_journal_pin_drop(&c->journal, &as->journal); @@ -1428,6 +1455,7 @@ static void btree_split(struct btree_update *as, struct btree_trans *trans, struct bch_fs *c = as->c; struct btree *parent = btree_node_parent(path, b); struct btree *n1, *n2 = NULL, *n3 = NULL; + struct btree_path *path1 = NULL, *path2 = NULL; u64 start_time = local_clock(); BUG_ON(!parent && (b != btree_node_root(c, b))); @@ -1450,6 +1478,16 @@ static void btree_split(struct btree_update *as, struct btree_trans *trans, six_unlock_write(&n2->c.lock); six_unlock_write(&n1->c.lock); + path1 = get_unlocked_mut_path(trans, path->btree_id, n1->c.level, n1->key.k.p); + six_lock_increment(&n1->c.lock, SIX_LOCK_intent); + mark_btree_node_locked(trans, path1, n1->c.level, SIX_LOCK_intent); + bch2_btree_path_level_init(trans, path1, n1); + + path2 = get_unlocked_mut_path(trans, path->btree_id, n2->c.level, n2->key.k.p); + six_lock_increment(&n2->c.lock, SIX_LOCK_intent); + mark_btree_node_locked(trans, path2, n2->c.level, SIX_LOCK_intent); + bch2_btree_path_level_init(trans, path2, n2); + bch2_btree_update_add_new_node(as, n1); bch2_btree_node_write(c, n1, SIX_LOCK_intent, 0); @@ -1467,6 +1505,12 @@ static void btree_split(struct btree_update *as, struct btree_trans *trans, /* Depth increases, make a new root */ n3 = __btree_root_alloc(as, trans, b->c.level + 1); + path2->locks_want++; + BUG_ON(btree_node_locked(path2, n3->c.level)); + six_lock_increment(&n3->c.lock, SIX_LOCK_intent); + mark_btree_node_locked(trans, path2, n3->c.level, SIX_LOCK_intent); + bch2_btree_path_level_init(trans, path2, n3); + n3->sib_u64s[0] = U16_MAX; n3->sib_u64s[1] = U16_MAX; @@ -1480,6 +1524,11 @@ static void btree_split(struct btree_update *as, struct btree_trans *trans, bch2_btree_build_aux_trees(n1); six_unlock_write(&n1->c.lock); + path1 = get_unlocked_mut_path(trans, path->btree_id, n1->c.level, n1->key.k.p); + six_lock_increment(&n1->c.lock, SIX_LOCK_intent); + mark_btree_node_locked(trans, path1, n1->c.level, SIX_LOCK_intent); + bch2_btree_path_level_init(trans, path1, n1); + bch2_btree_update_add_new_node(as, n1); bch2_btree_node_write(c, n1, SIX_LOCK_intent, 0); @@ -1526,6 +1575,15 @@ static void btree_split(struct btree_update *as, struct btree_trans *trans, six_unlock_intent(&n2->c.lock); six_unlock_intent(&n1->c.lock); + if (path2) { + __bch2_btree_path_unlock(trans, path2); + bch2_path_put(trans, path2, true); + } + if (path1) { + __bch2_btree_path_unlock(trans, path1); + bch2_path_put(trans, path1, true); + } + bch2_trans_verify_locks(trans); bch2_time_stats_update(&c->times[n2 @@ -1642,7 +1700,7 @@ int __bch2_foreground_maybe_merge(struct btree_trans *trans, enum btree_node_sibling sib) { struct bch_fs *c = trans->c; - struct btree_path *sib_path = NULL; + struct btree_path *sib_path = NULL, *new_path = NULL; struct btree_update *as; struct bkey_format_state new_s; struct bkey_format new_f; @@ -1766,6 +1824,11 @@ int __bch2_foreground_maybe_merge(struct btree_trans *trans, bch2_btree_build_aux_trees(n); six_unlock_write(&n->c.lock); + new_path = get_unlocked_mut_path(trans, path->btree_id, n->c.level, n->key.k.p); + six_lock_increment(&n->c.lock, SIX_LOCK_intent); + mark_btree_node_locked(trans, new_path, n->c.level, SIX_LOCK_intent); + bch2_btree_path_level_init(trans, new_path, n); + bch2_btree_node_write(c, n, SIX_LOCK_intent, 0); bkey_init(&delete.k); @@ -1795,6 +1858,8 @@ int __bch2_foreground_maybe_merge(struct btree_trans *trans, bch2_time_stats_update(&c->times[BCH_TIME_btree_node_merge], start_time); out: err: + if (new_path) + bch2_path_put(trans, new_path, true); bch2_path_put(trans, sib_path, true); bch2_trans_verify_locks(trans); return ret; @@ -1809,6 +1874,7 @@ int bch2_btree_node_rewrite(struct btree_trans *trans, unsigned flags) { struct bch_fs *c = trans->c; + struct btree_path *new_path = NULL; struct btree *n, *parent; struct btree_update *as; int ret; @@ -1830,6 +1896,11 @@ int bch2_btree_node_rewrite(struct btree_trans *trans, bch2_btree_build_aux_trees(n); six_unlock_write(&n->c.lock); + new_path = get_unlocked_mut_path(trans, iter->btree_id, n->c.level, n->key.k.p); + six_lock_increment(&n->c.lock, SIX_LOCK_intent); + mark_btree_node_locked(trans, new_path, n->c.level, SIX_LOCK_intent); + bch2_btree_path_level_init(trans, new_path, n); + trace_and_count(c, btree_node_rewrite, c, b); bch2_btree_node_write(c, n, SIX_LOCK_intent, 0); @@ -1850,6 +1921,7 @@ int bch2_btree_node_rewrite(struct btree_trans *trans, six_unlock_intent(&n->c.lock); bch2_btree_update_done(as, trans); + bch2_path_put(trans, new_path, true); out: bch2_btree_path_downgrade(trans, iter->path); return ret; |