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| author | Kent Overstreet <kent.overstreet@linux.dev> | 2023-01-03 01:53:02 +0300 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-10-23 00:09:52 +0300 |
| commit | 7ffb6a7ec6712eb1ba84a80137c2f712e67c4171 (patch) | |
| tree | 0d05e725b41817a28164f1ba6ee19747d010bbf6 /fs/bcachefs/io.c | |
| parent | dbe17f18838df6d0facf51b43cdc5efd372c28d6 (diff) | |
| download | linux-7ffb6a7ec6712eb1ba84a80137c2f712e67c4171.tar.xz | |
bcachefs: Fix deadlock on nocow locks in data move path
The recent nocow locking rework introduced a deadlock in the data move
path: the new nocow locking scheme uses a hash table with a fixed size
array for chaining, meaning on hash collision we may have to wait for
other locks to be released before we can lock a bucket.
And since the data move path needs to submit writes from the same thread
that's taking nocow locks and submitting reads, this introduces a
deadlock.
This shouldn't happen often in practice, but since the data move path
can keep large numbers of IOs in flight simultaneously, it's something
we have to handle.
This patch makes move_ctxt_wait_event() available to
bch2_data_update_init() and uses it when appropriate, which is our
normal solution to this kind of thing.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'fs/bcachefs/io.c')
| -rw-r--r-- | fs/bcachefs/io.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/fs/bcachefs/io.c b/fs/bcachefs/io.c index fe0c4b58e525..93d300812b4b 100644 --- a/fs/bcachefs/io.c +++ b/fs/bcachefs/io.c @@ -1961,7 +1961,7 @@ static void promote_start(struct promote_op *op, struct bch_read_bio *rbio) bch2_data_update_read_done(&op->write, rbio->pick.crc); } -static struct promote_op *__promote_alloc(struct bch_fs *c, +static struct promote_op *__promote_alloc(struct btree_trans *trans, enum btree_id btree_id, struct bkey_s_c k, struct bpos pos, @@ -1970,6 +1970,7 @@ static struct promote_op *__promote_alloc(struct bch_fs *c, unsigned sectors, struct bch_read_bio **rbio) { + struct bch_fs *c = trans->c; struct promote_op *op = NULL; struct bio *bio; unsigned pages = DIV_ROUND_UP(sectors, PAGE_SECTORS); @@ -2013,7 +2014,7 @@ static struct promote_op *__promote_alloc(struct bch_fs *c, bio = &op->write.op.wbio.bio; bio_init(bio, NULL, bio->bi_inline_vecs, pages, 0); - ret = bch2_data_update_init(c, &op->write, + ret = bch2_data_update_init(trans, NULL, &op->write, writepoint_hashed((unsigned long) current), opts, (struct data_update_opts) { @@ -2037,16 +2038,17 @@ err: } noinline -static struct promote_op *promote_alloc(struct bch_fs *c, - struct bvec_iter iter, - struct bkey_s_c k, - struct extent_ptr_decoded *pick, - struct bch_io_opts opts, - unsigned flags, - struct bch_read_bio **rbio, - bool *bounce, - bool *read_full) +static struct promote_op *promote_alloc(struct btree_trans *trans, + struct bvec_iter iter, + struct bkey_s_c k, + struct extent_ptr_decoded *pick, + struct bch_io_opts opts, + unsigned flags, + struct bch_read_bio **rbio, + bool *bounce, + bool *read_full) { + struct bch_fs *c = trans->c; bool promote_full = *read_full || READ_ONCE(c->promote_whole_extents); /* data might have to be decompressed in the write path: */ unsigned sectors = promote_full @@ -2060,7 +2062,7 @@ static struct promote_op *promote_alloc(struct bch_fs *c, if (!should_promote(c, k, pos, opts, flags)) return NULL; - promote = __promote_alloc(c, + promote = __promote_alloc(trans, k.k->type == KEY_TYPE_reflink_v ? BTREE_ID_reflink : BTREE_ID_extents, @@ -2667,7 +2669,7 @@ retry_pick: } if (orig->opts.promote_target) - promote = promote_alloc(c, iter, k, &pick, orig->opts, flags, + promote = promote_alloc(trans, iter, k, &pick, orig->opts, flags, &rbio, &bounce, &read_full); if (!read_full) { |