| Message ID | 20201126031834.40807-1-yukuai3@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-throttle: don't check whether or not lower limit is valid if CONFIG_BLK_DEV_THROTTLING_LOW is off | expand |
On Thu, Nov 26, 2020 at 11:18:34AM +0800, Yu Kuai wrote: > blk_throtl_update_limit_valid() will search for descendants to see if > 'LIMIT_LOW' of bps/iops and READ/WRITE is nonzero. However, they're always > zero if CONFIG_BLK_DEV_THROTTLING_LOW is not set, furthermore, a lot of > time will be wasted to iterate descendants. > > Thus do nothing in blk_throtl_update_limit_valid() in such situation. > > Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Thanks.
On 11/25/20 8:18 PM, Yu Kuai wrote: > blk_throtl_update_limit_valid() will search for descendants to see if > 'LIMIT_LOW' of bps/iops and READ/WRITE is nonzero. However, they're always > zero if CONFIG_BLK_DEV_THROTTLING_LOW is not set, furthermore, a lot of > time will be wasted to iterate descendants. > > Thus do nothing in blk_throtl_update_limit_valid() in such situation. Applied, thanks.
diff --git a/block/blk-throttle.c b/block/blk-throttle.c index b771c4299982..d52cac9f3a7c 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -587,6 +587,7 @@ static void throtl_pd_online(struct blkg_policy_data *pd) tg_update_has_rules(tg); } +#ifdef CONFIG_BLK_DEV_THROTTLING_LOW static void blk_throtl_update_limit_valid(struct throtl_data *td) { struct cgroup_subsys_state *pos_css; @@ -607,6 +608,11 @@ static void blk_throtl_update_limit_valid(struct throtl_data *td) td->limit_valid[LIMIT_LOW] = low_valid; } +#else +static inline void blk_throtl_update_limit_valid(struct throtl_data *td) +{ +} +#endif static void throtl_upgrade_state(struct throtl_data *td); static void throtl_pd_offline(struct blkg_policy_data *pd)
blk_throtl_update_limit_valid() will search for descendants to see if 'LIMIT_LOW' of bps/iops and READ/WRITE is nonzero. However, they're always zero if CONFIG_BLK_DEV_THROTTLING_LOW is not set, furthermore, a lot of time will be wasted to iterate descendants. Thus do nothing in blk_throtl_update_limit_valid() in such situation. Signed-off-by: Yu Kuai <yukuai3@huawei.com> --- block/blk-throttle.c | 6 ++++++ 1 file changed, 6 insertions(+)