diff mbox series

[v2,08/10] blk-throttle: remove repeat check of elapsed time from last upgrade in throtl_hierarchy_can_downgrade

Message ID 20221129030147.27400-9-shikemeng@huawei.com (mailing list archive)
State New, archived
Headers show
Series A few bugfix and cleanup patches for blk-throttle | expand

Commit Message

Kemeng Shi Nov. 29, 2022, 3:01 a.m. UTC 
There is no need to check elapsed time from last upgrade for each node in
hierarchy. Move this check before traversing as throtl_can_upgrade do
to remove repeat check.

Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
---
 block/blk-throttle.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

Comments

Tejun Heo Nov. 30, 2022, 9:34 p.m. UTC | #1 
On Tue, Nov 29, 2022 at 11:01:45AM +0800, Kemeng Shi wrote:
> There is no need to check elapsed time from last upgrade for each node in
> hierarchy. Move this check before traversing as throtl_can_upgrade do
> to remove repeat check.
> 
> Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
> Reported-by: kernel test robot <lkp@intel.com>

Acked-by: Tejun Heo <tj@kernel.org>
diff mbox series

Patch

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 3ddd8a15aa3f..94d850b57462 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1955,8 +1955,7 @@  static bool throtl_tg_can_downgrade(struct throtl_grp *tg)
 	 * If cgroup is below low limit, consider downgrade and throttle other
 	 * cgroups
 	 */
-	if (time_after_eq(now, td->low_upgrade_time + td->throtl_slice) &&
-	    time_after_eq(now, tg_last_low_overflow_time(tg) +
+	if (time_after_eq(now, tg_last_low_overflow_time(tg) +
 					td->throtl_slice) &&
 	    (!throtl_tg_is_idle(tg) ||
 	     !list_empty(&tg_to_blkg(tg)->blkcg->css.children)))
@@ -1966,6 +1965,11 @@  static bool throtl_tg_can_downgrade(struct throtl_grp *tg)
 
 static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg)
 {
+	struct throtl_data *td = tg->td;
+
+	if (time_before(jiffies, td->low_upgrade_time + td->throtl_slice))
+		return false;
+
 	while (true) {
 		if (!throtl_tg_can_downgrade(tg))
 			return false;