diff mbox series

[08/11] blk-throttle: remove repeat check of elapsed time from last upgrade in throtl_hierarchy_can_downgrade

Message ID 20221123060401.20392-9-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. 23, 2022, 6:03 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>
---
 block/blk-throttle.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

Comments

Tejun Heo Nov. 23, 2022, 6:28 p.m. UTC | #1 
On Wed, Nov 23, 2022 at 02:03:58PM +0800, Kemeng Shi wrote:
>  static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg)
>  {
> +	if (time_before(now, tg->td->low_upgrade_time + td->throtl_slice))
> +		return false;

Does this even build? Where is td defined?
Kemeng Shi Nov. 24, 2022, 12:58 p.m. UTC | #2 
on 11/24/2022 2:28 AM, Tejun Heo wrote:
> On Wed, Nov 23, 2022 at 02:03:58PM +0800, Kemeng Shi wrote:
>>  static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg)
>>  {
>> +	if (time_before(now, tg->td->low_upgrade_time + td->throtl_slice))
>> +		return false;
> 
> Does this even build? Where is td defined?
Sorry for this mistake, CONFIG_BLK_DEV_THROTTLING_LOW seems not be set on
default. I will fix this and build with CONFIG_BLK_DEV_THROTTLING_LOW
set.
diff mbox series

Patch

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index bd07f562c799..3eccc7af4368 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1932,8 +1932,7 @@  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)))
@@ -1943,6 +1942,9 @@  static bool throtl_tg_can_downgrade(struct throtl_grp *tg)
 
 static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg)
 {
+	if (time_before(now, tg->td->low_upgrade_time + td->throtl_slice))
+		return false;
+
 	while (true) {
 		if (!throtl_tg_can_downgrade(tg))
 			return false;