Re: [PATCH -next] blk-cgroup: move congestion_count to struct blkcg

From: xiujianfeng
Date: Mon Jul 15 2024 - 08:35:50 EST




On 2024/7/14 1:41, Tejun Heo wrote:
> Hello,
>
> Sorry about the previous reply. I completely misread the patch.
>
> On Fri, Jul 12, 2024 at 08:51:41AM +0000, Xiu Jianfeng wrote:
> ...
>> only compiling tested
>
> It'd be better if there's a bit more verification.
>
>> diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
>> index 37e6cc91d576..01d3408c2fc6 100644
>> --- a/block/blk-cgroup.c
>> +++ b/block/blk-cgroup.c
>> @@ -2183,11 +2183,13 @@ void blk_cgroup_bio_start(struct bio *bio)
>> bool blk_cgroup_congested(void)
>> {
>> struct cgroup_subsys_state *css;
>> + struct blkcg *blkcg;
>
> It'd be better to define this within the loop.
>
>> bool ret = false;
>>
>> rcu_read_lock();
>> for (css = blkcg_css(); css; css = css->parent) {
>
> Also, if we're now dealing with blkcg's, there's no reason to go blkcg ->
> css -> blkcg again. It'd be better to get the initial blkcg and then walk up
> using blkcg_parent().

Thanks, will do in v2.


>
>> @@ -95,6 +95,8 @@ struct blkcg {
>> struct cgroup_subsys_state css;
>> spinlock_t lock;
>> refcount_t online_pin;
>> + /* If there is block congestion on this cgroup. */
>> + atomic_t congestion_count;
>
> Can you please match the indentation?

Sure, I copied it from the original place, will do in v2

>
> Thanks.
>