Re: [PATCH 3/3] blk-cgroup: move async bio punt state to blkcg

["yu kuai" <yukuai@fygo.io>]

Hi,

在 2026/9/6 19:01, Nilay Shroff 写道:
> On 8/23/26 7:00 PM, Yu Kuai wrote:
>> @@ -111,10 +104,15 @@ struct blkcg {
>>       /*
>>        * List of updated percpu blkg_iostat_set's since the last flush.
>>        */
>>       struct llist_head __percpu    *lhead;
>>   +#ifdef CONFIG_BLK_CGROUP_PUNT_BIO
>> +    spinlock_t            async_bio_lock; /* protects async_bios */
>> +    struct bio_list            async_bios;
>> +    struct work_struct        async_bio_work;
>> +#endif
>>   #ifdef CONFIG_BLK_CGROUP_FC_APPID
>>       char                            fc_app_id[FC_APPID_LEN];
>>   #endif
>>   #ifdef CONFIG_CGROUP_WRITEBACK
>>       struct list_head        cgwb_list;
>
> As I mentioned, Clang context annotations are now officially supported
> in the block layer. Since you're touching this code, I suggest annotating
> async_bios with __guarded_by(&async_bio_lock) as well.
>
> This would allow the Clang thread-safety analyzer to verify that every
> access to async_bios is properly protected by async_bio_lock.
Sounds reasonable, will do this in the next version.
>
> Thanks,
> --Nilay

-- 
Thanks,
Kuai