blkcg: kill unused field nr_undestroyed_grps

'nr_undestroyed_grps' in struct throtl_data was used to count
the number of throtl_grp related with throtl_data, but now
throtl_grp is tracked by blkcg_gq, so it is useless anymore.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 47a3e540631a38b123a078350d28ae457753ebbd..c5494e40323992705ad56167267ea971251b0569 100644 (file)
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -145,11 +145,6 @@ struct throtl_data
        /* Total Number of queued bios on READ and WRITE lists */
        unsigned int nr_queued[2];
 
-       /*
-        * number of total undestroyed groups
-        */
-       unsigned int nr_undestroyed_grps;
-
        /* Work for dispatching throttled bios */
        struct work_struct dispatch_work;
 };