On Fri, 12 Apr 2019, Huaisheng Ye wrote: > From: Huaisheng Ye <yehs1@xxxxxxxxxx> > > In functions writecache_discard and writecache_find_entry, there is > high probablity that the pointer of structure rb_node doesn't equal > to NULL. Add unlikly for the pointer node. > > Signed-off-by: Huaisheng Ye <yehs1@xxxxxxxxxx> Acked-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> > --- > drivers/md/dm-writecache.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c > index 5b4d1c1..cfbbfbc 100644 > --- a/drivers/md/dm-writecache.c > +++ b/drivers/md/dm-writecache.c > @@ -571,7 +571,7 @@ static struct wc_entry *writecache_find_entry(struct dm_writecache *wc, > node = rb_prev(&e->rb_node); > else > node = rb_next(&e->rb_node); > - if (!node) > + if (unlikely(!node)) > return e; > e2 = container_of(node, struct wc_entry, rb_node); > if (read_original_sector(wc, e2) != block) > @@ -804,7 +804,7 @@ static void writecache_discard(struct dm_writecache *wc, sector_t start, sector_ > writecache_free_entry(wc, e); > } > > - if (!node) > + if (unlikely(!node)) > break; > > e = container_of(node, struct wc_entry, rb_node); > -- > 1.8.3.1 > -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
