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| author | Coly Li <colyli@suse.de> | 2019-06-28 19:59:55 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-09-16 08:23:20 +0200 |
| commit | b622ba2bcd4edf70a307db16e94f2292563bdc8d (patch) | |
| tree | 7cf2186f9dd0680f262df5927e243bfb5c4c4d63 /drivers/md | |
| parent | bb70b2729b7a425f840e01c64348ed5c63699de2 (diff) | |
| download | linux-stable-b622ba2bcd4edf70a307db16e94f2292563bdc8d.tar.gz linux-stable-b622ba2bcd4edf70a307db16e94f2292563bdc8d.tar.bz2 linux-stable-b622ba2bcd4edf70a307db16e94f2292563bdc8d.zip | |
bcache: only clear BTREE_NODE_dirty bit when it is set
In bch_btree_cache_free() and btree_node_free(), BTREE_NODE_dirty is
always set no matter btree node is dirty or not. The code looks like
this,
if (btree_node_dirty(b))
btree_complete_write(b, btree_current_write(b));
clear_bit(BTREE_NODE_dirty, &b->flags);
Indeed if btree_node_dirty(b) returns false, it means BTREE_NODE_dirty
bit is cleared, then it is unnecessary to clear the bit again.
This patch only clears BTREE_NODE_dirty when btree_node_dirty(b) is
true (the bit is set), to save a few CPU cycles.
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/bcache/btree.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index 773f5fdad25f..3fbadf2058a6 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -778,10 +778,10 @@ void bch_btree_cache_free(struct cache_set *c) while (!list_empty(&c->btree_cache)) { b = list_first_entry(&c->btree_cache, struct btree, list); - if (btree_node_dirty(b)) + if (btree_node_dirty(b)) { btree_complete_write(b, btree_current_write(b)); - clear_bit(BTREE_NODE_dirty, &b->flags); - + clear_bit(BTREE_NODE_dirty, &b->flags); + } mca_data_free(b); } @@ -1069,9 +1069,10 @@ static void btree_node_free(struct btree *b) mutex_lock(&b->write_lock); - if (btree_node_dirty(b)) + if (btree_node_dirty(b)) { btree_complete_write(b, btree_current_write(b)); - clear_bit(BTREE_NODE_dirty, &b->flags); + clear_bit(BTREE_NODE_dirty, &b->flags); + } mutex_unlock(&b->write_lock); |