lkml.org 
[lkml]   [2020]   [Dec]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 07/15] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1
Date
If the scheduler cannot find an allowed CPU for a task,
cpuset_cpus_allowed_fallback() will widen the affinity to cpu_possible_mask
if cgroup v1 is in use.

In preparation for allowing architectures to provide their own fallback
mask, just return early if we're not using cgroup v2 and allow
select_fallback_rq() to figure out the mask by itself.

Cc: Li Zefan <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
kernel/cgroup/cpuset.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 57b5b5d0a5fd..e970737c3ed2 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -3299,9 +3299,11 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)

void cpuset_cpus_allowed_fallback(struct task_struct *tsk)
{
+ if (!is_in_v2_mode())
+ return; /* select_fallback_rq will try harder */
+
rcu_read_lock();
- do_set_cpus_allowed(tsk, is_in_v2_mode() ?
- task_cs(tsk)->cpus_allowed : cpu_possible_mask);
+ do_set_cpus_allowed(tsk, task_cs(tsk)->cpus_allowed);
rcu_read_unlock();

/*
--
2.29.2.576.ga3fc446d84-goog
\
 
 \ /
  Last update: 2020-12-08 14:33    [W:0.943 / U:0.680 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site