diff options
| author | Kent Overstreet <kent.overstreet@linux.dev> | 2024-12-08 04:11:21 -0500 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2024-12-21 01:36:22 -0500 |
| commit | 49f2d182638a54ecda9cb35ede5224f8d9f5f2e6 (patch) | |
| tree | d4f1b78c660904483af69fe89cb2f82b3e407dcd /fs/bcachefs/btree_gc.c | |
| parent | 54dacdada6de8d97e7ca7e51eadc96c61032bdb4 (diff) | |
bcachefs: Kill unnecessary mark_lock usage
We can't hold mark_lock while calling fsck_err() - that's a deadlock,
mark_lock is meant to be a leaf node lock.
It's also unnecessary for gc_bucket() and bucket_gen(); rcu suffices
since the bucket_gens array describes its size, and we can't race with
device removal or resize during gc/fsck since that takes state lock.
Reported-by: syzbot+38641fcbda1aaffefdd4@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'fs/bcachefs/btree_gc.c')
| -rw-r--r-- | fs/bcachefs/btree_gc.c | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c index 24f2f3bdf704..e5ba7d1429b9 100644 --- a/fs/bcachefs/btree_gc.c +++ b/fs/bcachefs/btree_gc.c @@ -811,7 +811,6 @@ static int bch2_alloc_write_key(struct btree_trans *trans, old = bch2_alloc_to_v4(k, &old_convert); gc = new = *old; - percpu_down_read(&c->mark_lock); __bucket_m_to_alloc(&gc, *gc_bucket(ca, iter->pos.offset)); old_gc = gc; @@ -822,7 +821,6 @@ static int bch2_alloc_write_key(struct btree_trans *trans, gc.data_type = old->data_type; gc.dirty_sectors = old->dirty_sectors; } - percpu_up_read(&c->mark_lock); /* * gc.data_type doesn't yet include need_discard & need_gc_gen states - @@ -840,11 +838,9 @@ static int bch2_alloc_write_key(struct btree_trans *trans, * safe w.r.t. transaction restarts, so fixup the gc_bucket so * we don't run it twice: */ - percpu_down_read(&c->mark_lock); struct bucket *gc_m = gc_bucket(ca, iter->pos.offset); gc_m->data_type = gc.data_type; gc_m->dirty_sectors = gc.dirty_sectors; - percpu_up_read(&c->mark_lock); } if (fsck_err_on(new.data_type != gc.data_type, @@ -1088,7 +1084,6 @@ static int gc_btree_gens_key(struct btree_trans *trans, if (unlikely(test_bit(BCH_FS_going_ro, &c->flags))) return -EROFS; - percpu_down_read(&c->mark_lock); rcu_read_lock(); bkey_for_each_ptr(ptrs, ptr) { struct bch_dev *ca = bch2_dev_rcu(c, ptr->dev); @@ -1097,7 +1092,6 @@ static int gc_btree_gens_key(struct btree_trans *trans, if (dev_ptr_stale(ca, ptr) > 16) { rcu_read_unlock(); - percpu_up_read(&c->mark_lock); goto update; } } @@ -1112,7 +1106,6 @@ static int gc_btree_gens_key(struct btree_trans *trans, *gen = ptr->gen; } rcu_read_unlock(); - percpu_up_read(&c->mark_lock); return 0; update: u = bch2_bkey_make_mut(trans, iter, &k, 0); |