Re: [PATCH] block: remove redundant explicit memory barrier from rq_qos waiter and waker

From: Muchun Song
Date: Tue Oct 22 2024 - 02:33:17 EST




> On Oct 21, 2024, at 21:45, Jens Axboe <axboe@xxxxxxxxx> wrote:
>
> On 10/21/24 2:52 AM, Muchun Song wrote:
>> The memory barriers in list_del_init_careful() and list_empty_careful()
>> in pairs already handle the proper ordering between data.got_token
>> and data.wq.entry. So remove the redundant explicit barriers. And also
>> change a "break" statement to "return" to avoid redundant calling of
>> finish_wait().
>
> Not sure why you didn't CC Omar on this one, as he literally just last
> week fixed an issue related to this.

Hi Jens,

Yes. I only CC the author of patch of adding the barriers, I thought
they should be more confident about this. Thanks for your reminder.
I saw Omar's great fix. And thanks for you help me CC Omar. I think
he'll be also suitable for commenting on this patch.

Muchun,
Thanks.