Subject: Re: [PATCH -next] block: Revert "block: increase BLKCG_MAX_POLS"
To:     Oleksandr Natalenko <oleksandr@natalenko.name>, tj@kernel.org,
        axboe@kernel.dk, Yu Kuai <yukuai1@huaweicloud.com>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        yi.zhang@huawei.com, yangerkun@huawei.com,
        "yukuai (C)" <yukuai3@huawei.com>
References: <20230203081357.1385168-1-yukuai1@huaweicloud.com>
 <2666358.mvXUDI8C0e@natalenko.name>
From:   Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <957f8218-ef4d-7841-0bb2-07d8de6ae28d@huaweicloud.com>
Date:   Fri, 3 Feb 2023 16:13:38 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <2666358.mvXUDI8C0e@natalenko.name>
Content-Type: text/plain; charset=gbk; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk

Hi,

?? 2023/02/03 15:59, Oleksandr Natalenko д??:
> Hello.
> 
> On p??tek 3. ??nora 2023 9:13:57 CET Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> This reverts commit ec645dc96699ea6c37b6de86c84d7288ea9a4ddf.
>>
>> This can save some memory, because after commit 0f7839955114 ("Revert
>> "block/mq-deadline: Add cgroup support""), there are total 5 policies.
>>
>> Signed-off-by: Yu Kuai <yukuai3@huawei.com>
>> ---
>>   include/linux/blkdev.h | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
>> index 41a41561b773..c6861c7fdad9 100644
>> --- a/include/linux/blkdev.h
>> +++ b/include/linux/blkdev.h
>> @@ -54,7 +54,7 @@ extern struct class block_class;
>>    * Maximum number of blkcg policies allowed to be registered concurrently.
>>    * Defined here to simplify include dependency.
>>    */
>> -#define BLKCG_MAX_POLS		6
>> +#define BLKCG_MAX_POLS		5
>>   
>>   #define DISK_MAX_PARTS			256
>>   #define DISK_NAME_LEN			32
> 
> Last time I asked about reverting this change, it was suggested that we may keep it [1].
> 
> [1] https://lore.kernel.org/linux-block/1dc051a8-4d59-8137-2406-f74026b170bd@kernel.dk/
> 

I see now, thanks for the reply.

Kuai