diff options
author | Coly Li <colyli@suse.de> | 2020-01-23 20:01:42 +0300 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2020-01-23 21:40:02 +0300 |
commit | e3de04469a49ee09c89e80bf821508df458ccee6 (patch) | |
tree | 194f994ea2493a2a6f28680acbd2ecb3ef14d5ff | |
parent | d5c9c470b01177e4d90cdbf178b8c7f37f5b8795 (diff) | |
download | linux-e3de04469a49ee09c89e80bf821508df458ccee6.tar.xz |
bcache: reap from tail of c->btree_cache in bch_mca_scan()
When shrink btree node cache from c->btree_cache in bch_mca_scan(),
no matter the selected node is reaped or not, it will be rotated from
the head to the tail of c->btree_cache list. But in bcache journal
code, when flushing the btree nodes with oldest journal entry, btree
nodes are iterated and slected from the tail of c->btree_cache list in
btree_flush_write(). The list_rotate_left() in bch_mca_scan() will
make btree_flush_write() iterate more nodes in c->btree_list in reverse
order.
This patch just reaps the selected btree node cache, and not move it
from the head to the tail of c->btree_cache list. Then bch_mca_scan()
will not mess up c->btree_cache list to btree_flush_write().
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | drivers/md/bcache/btree.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index c3a314deb09d..fa872df4e770 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -747,19 +747,19 @@ static unsigned long bch_mca_scan(struct shrinker *shrink, i++; } - for (; (nr--) && i < btree_cache_used; i++) { - if (list_empty(&c->btree_cache)) + list_for_each_entry_safe_reverse(b, t, &c->btree_cache, list) { + if (nr <= 0 || i >= btree_cache_used) goto out; - b = list_first_entry(&c->btree_cache, struct btree, list); - list_rotate_left(&c->btree_cache); - if (!mca_reap(b, 0, false)) { mca_bucket_free(b); mca_data_free(b); rw_unlock(true, b); freed++; } + + nr--; + i++; } out: mutex_unlock(&c->bucket_lock); |