[PATCH 02/10] workqueue: use cpu_possible_mask instead of cpu_active_mask to break affinity

From: Lai Jiangshan
Date: Mon Dec 14 2020 - 09:57:48 EST


From: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>

There might be other CPU online. The workers losing binding on its CPU
should have chance to work on those later onlined CPUs.

Fixes: 06249738a41a ("workqueue: Manually break affinity on hotplug")
Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>
---
kernel/workqueue.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index aba71ab359dd..1f5b8385c0cf 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4909,8 +4909,9 @@ static void unbind_workers(int cpu)

raw_spin_unlock_irq(&pool->lock);

+ /* don't rely on the scheduler to force break affinity for us. */
for_each_pool_worker(worker, pool)
- WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_active_mask) < 0);
+ WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_possible_mask) < 0);

mutex_unlock(&wq_pool_attach_mutex);

--
2.19.1.6.gb485710b