On 8/11/23 7:42 PM, Yu Kuai wrote:
> Hi, Jens
>
> ? 2023/08/11 22:12, Jens Axboe ??:
>>
>> On Thu, 10 Aug 2023 11:51:11 +0800, Li Lingfeng wrote:
>>> Commit a13696b83da4 ("blk-iolatency: Make initialization lazy") adds
>>> a mutex named "init_mutex" in blk_iolatency_try_init for the race
>>> condition of initializing RQ_QOS_LATENCY.
>>> Now a new lock has been add to struct request_queue by commit a13bd91be223
>>> ("block/rq_qos: protect rq_qos apis with a new lock"). And it has been
>>> held in blkg_conf_open_bdev before calling blk_iolatency_init.
>>> So it's not necessary to keep init_mutex in blk_iolatency_try_init, just
>>> remove it.
>>>
>>> [...]
>>
>> Applied, thanks!
>>
>> [1/1] block: remove init_mutex and open-code blk_iolatency_try_init
>> commit: 4eb44d10766ac0fae5973998fd2a0103df1d3fe1
>
> This version has a minor problem that pss in mutex for
> lockdep_assert_held() is not a pointer:
>
>> lockdep_assert_held(ctx.bdev->bd_queue->rq_qos_mutex);
>
> should be:
> lockdep_assert_held(&ctx.bdev->bd_queue->rq_qos_mutex);
Yes, looked like that patch didn't get compiled... Shame.
> Perhaps can you drop this patch for now, and Lingfeng can send a v4?
I did fix that up 2 days ago myself.
--
Jens Axboe
