回复: [PATCH] PM: remove PF_WQ_WORKER mask

["Zhang, Qiang" <Qiang.Zhang@windriver.com>]

________________________________________
发件人: Rafael J. Wysocki <rafael@kernel.org>
发送时间: 2021年1月28日 2:16
收件人: Zhang, Qiang
抄送: Rafael Wysocki; Linux PM; Linux Kernel Mailing List
主题: Re: [PATCH] PM: remove PF_WQ_WORKER mask

[Please note: This e-mail is from an EXTERNAL e-mail address]

On Mon, Jan 25, 2021 at 5:01 AM <qiang.zhang@windriver.com> wrote:
>
> From: Zqiang <qiang.zhang@windriver.com>
>
> Due to kworker also is kernel thread, it's already included
> PF_KTHREAD mask, so remove PF_WQ_WORKER mask.

>So you are saying that all threads having PF_WQ_WORKER set must also
>have PF_KTHREAD set, right?

  yes
  #define PF_KTHREAD              0x00200000
  #define PF_WQ_WORKER          0x00000020
  I tracing kwoker's task->flags as follows:
  comm kworker/1:0, cpu 1, task->flags 0x4208060, delayed 3, func intel_fbc_work_fn

Thanks
Qiang

>That sounds correct, so I'm going to rewrite the changelog and apply
>the patch as 5.12 material, thanks!

> Signed-off-by: Zqiang <qiang.zhang@windriver.com>
> ---
>  kernel/power/process.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/power/process.c b/kernel/power/process.c
> index 45b054b7b5ec..50cc63534486 100644
> --- a/kernel/power/process.c
> +++ b/kernel/power/process.c
> @@ -235,7 +235,7 @@ void thaw_kernel_threads(void)
>
>         read_lock(&tasklist_lock);
>         for_each_process_thread(g, p) {
> -               if (p->flags & (PF_KTHREAD | PF_WQ_WORKER))
> +               if (p->flags & PF_KTHREAD)
>                         __thaw_task(p);
>         }
>         read_unlock(&tasklist_lock);
> --
> 2.17.1
>