Re: [PATCH v2 4/6] cgroup/cpuset: Iterate only if DEADLINE tasks are present

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 5/3/23 03:22, Juri Lelli wrote:
update_tasks_root_domain currently iterates over all tasks even if no
DEADLINE task is present on the cpuset/root domain for which bandwidth
accounting is being rebuilt. This has been reported to introduce 10+ ms
delays on suspend-resume operations.

Skip the costly iteration for cpusets that don't contain DEADLINE tasks.

Reported-by: Qais Yousef <qyousef@xxxxxxxxxxx>
Link: https://lore.kernel.org/lkml/20230206221428.2125324-1-qyousef@xxxxxxxxxxx/
Signed-off-by: Juri Lelli <juri.lelli@xxxxxxxxxx>
---
  kernel/cgroup/cpuset.c | 3 +++
  1 file changed, 3 insertions(+)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index b9f4d5602517..6587df42cb61 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1090,6 +1090,9 @@ static void dl_update_tasks_root_domain(struct cpuset *cs)
  	struct css_task_iter it;
  	struct task_struct *task;
+ if (cs->nr_deadline_tasks == 0)
+		return;
+
  	css_task_iter_start(&cs->css, 0, &it);
while ((task = css_task_iter_next(&it)))
Reviewed-by: Waiman Long <longman@xxxxxxxxxx>




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]     [Monitors]

  Powered by Linux