From: Shenghui Wang Date: Mon, 8 Oct 2018 12:41:07 +0000 (+0800) Subject: bcache: account size of buckets used in uuid write to ca->meta_sectors_written X-Git-Tag: v4.20-rc1~191^2~109 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=7a55948d38eb9b274cbbdd56dc1dd4b96ebfbe04;p=linux.git bcache: account size of buckets used in uuid write to ca->meta_sectors_written UUIDs are considered as metadata. __uuid_write should add the number of buckets (in sectors) written to disk to ca->meta_sectors_written. Currently only 1 bucket is used in uuid write. Steps to test: 1) create a fresh backing device and a fresh cache device separately. The backing device didn't attach to any cache set. 2) cd /sys/block//bcache cat metadata_written // record the output value cat bucket_size 3) attach the backing device to cache set 4) cat metadata_written The output value is almost the same as the value in step 2 before the change. After the change, the value is bigger about 1 bucket size. Signed-off-by: Shenghui Wang Reviewed-by: Tang Junhui Signed-off-by: Coly Li Signed-off-by: Jens Axboe --- diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 30ba9aeb5ee8..5fd1466b34e4 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -418,6 +418,7 @@ static int __uuid_write(struct cache_set *c) { BKEY_PADDED(key) k; struct closure cl; + struct cache *ca; closure_init_stack(&cl); lockdep_assert_held(&bch_register_lock); @@ -429,6 +430,10 @@ static int __uuid_write(struct cache_set *c) uuid_io(c, REQ_OP_WRITE, 0, &k.key, &cl); closure_sync(&cl); + /* Only one bucket used for uuid write */ + ca = PTR_CACHE(c, &k.key, 0); + atomic_long_add(ca->sb.bucket_size, &ca->meta_sectors_written); + bkey_copy(&c->uuid_bucket, &k.key); bkey_put(c, &k.key); return 0;