Hi Chao, On Sun, Aug 21, 2016 at 11:21:30PM +0800, Chao Yu wrote: > From: Chao Yu <yuch...@huawei.com> > > In batch discard approach of fstrim will grab/release gc_mutex lock > repeatly, it makes contention of the lock becoming more intensive. > > So after one batch discards were issued in checkpoint and the lock > was released, it's better to do schedule() to increase opportunity > of grabbing gc_mutex lock for other competitors. > > Signed-off-by: Chao Yu <yuch...@huawei.com> > --- > fs/f2fs/segment.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 020767c..d0f74eb 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -1305,6 +1305,8 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct > fstrim_range *range) > mutex_unlock(&sbi->gc_mutex); > if (err) > break; > + > + schedule();
Hmm, if other thread is already waiting for gc_mutex, we don't need this here. In order to avoid long latency, wouldn't it be enough to reduce the batch size? Thanks, > } > out: > range->len = F2FS_BLK_TO_BYTES(cpc.trimmed); > -- > 2.7.2
