Re: [PATCH 04/19] bcache: fix wrong cache_misses statistics

Coly Li
2017-07-01T17:59:12Z

On 2017/7/1 上午4:42, bcache@lists.ewheeler.net wrote:
> From: Tang Junhui <tang.junhui@zte.com.cn>
>
> Some missed IOs are not counted into cache_misses, this patch fix this
> issue.

Could you please explain more about,
- which kind of missed I/O are mot counted
- where cache_missed is located

This will help the patch to be more understandable.

>
> Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
> Reviewed-by: Eric Wheeler <bcache@linux.ewheeler.net>
> Cc: stable@vger.kernel.org

[snip]

> @@ -758,7 +760,7 @@ static void cached_dev_read_done_bh(struct closure *cl)
> struct cached_dev *dc = container_of(s->d, struct cached_dev, disk);
>
> bch_mark_cache_accounting(s->iop.c, s->d,
> - !s->cache_miss, s->iop.bypass);
> + !s->cache_missed, s->iop.bypass);
> trace_bcache_read(s->orig_bio, !s->cache_miss, s->iop.bypass);

Should the above line be changed to,
trace_bcache_read(s->orig_bio, !s->cache_missed, s->iop.bypass);
as well ?

[snip]

Thanks.

--
Coly Li