2023-10-11 08:28:32

by Zqiang

Subject: [PATCH v2] workqueue: Use the kmem_cache_free() instead of kfree() to release pwq

Currently, the kfree() be used for pwq objects allocated with
kmem_cache_alloc() in alloc_and_link_pwqs(), this isn't wrong.
but usually, use "trace_kmem_cache_alloc/trace_kmem_cache_free"
to track memory allocation and free. this commit therefore use
kmem_cache_free() instead of kfree() in alloc_and_link_pwqs()
and also consistent with release of the pwq in rcu_free_pwq().

Signed-off-by: Zqiang <[email protected]>
---
kernel/workqueue.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ebe24a5e1435..6f74cab2bd5a 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4610,8 +4610,12 @@ static int alloc_and_link_pwqs(struct workqueue_struct *wq)

enomem:
if (wq->cpu_pwq) {
- for_each_possible_cpu(cpu)
- kfree(*per_cpu_ptr(wq->cpu_pwq, cpu));
+ for_each_possible_cpu(cpu) {
+ struct pool_workqueue *pwq = *per_cpu_ptr(wq->cpu_pwq, cpu);
+
+ if (pwq)
+ kmem_cache_free(pwq_cache, pwq);
+ }
free_percpu(wq->cpu_pwq);
wq->cpu_pwq = NULL;
}
--
2.17.1

2023-10-12 17:38:20

by Tejun Heo

Subject: Re: [PATCH v2] workqueue: Use the kmem_cache_free() instead of kfree() to release pwq

On Wed, Oct 11, 2023 at 04:27:59PM +0800, Zqiang wrote:
> Currently, the kfree() be used for pwq objects allocated with
> kmem_cache_alloc() in alloc_and_link_pwqs(), this isn't wrong.
> but usually, use "trace_kmem_cache_alloc/trace_kmem_cache_free"
> to track memory allocation and free. this commit therefore use
> kmem_cache_free() instead of kfree() in alloc_and_link_pwqs()
> and also consistent with release of the pwq in rcu_free_pwq().
>
> Signed-off-by: Zqiang <[email protected]>

Applied to wq/for-6.6-fixes.

Thanks.

--
tejun