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Message-ID: <cb1e2218-9a50-4c42-8a46-a35193208442@suse.cz>
Date: Mon, 26 Feb 2024 09:32:12 +0100
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Subject: Re: [PATCH] ceph: remove SLAB_MEM_SPREAD flag usage
To: Xiubo Li <xiubli@redhat.com>, Chengming Zhou <chengming.zhou@linux.dev>,
 idryomov@gmail.com, jlayton@kernel.org
Cc: ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org,
 linux-mm@kvack.org, roman.gushchin@linux.dev, Xiongwei.Song@windriver.com,
 Chengming Zhou <zhouchengming@bytedance.com>
References: <20240224134715.829225-1-chengming.zhou@linux.dev>
 <b6083c49-5240-40e3-a028-bb1ba63ccdd7@redhat.com>
 <d91e3235-395a-4e63-8ace-c14dfaf0a4fd@linux.dev>
 <35df81f5-feac-4373-87a3-d3a27ba9c9d4@redhat.com>
 <82c2553f-822e-40c2-9bf8-433689b3669d@linux.dev>
 <69589d2f-978d-4d14-9e5f-6bd6b3a43062@redhat.com>
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From: Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <69589d2f-978d-4d14-9e5f-6bd6b3a43062@redhat.com>
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On 2/26/24 05:54, Xiubo Li wrote:
> 
> On 2/26/24 12:30, Chengming Zhou wrote:
>> On 2024/2/26 12:23, Xiubo Li wrote:
>>> On 2/26/24 10:42, Chengming Zhou wrote:
>>>> On 2024/2/26 09:43, Xiubo Li wrote:
>>>>> Hi Chengming,
>>>>>
>>>>> Thanks for your patch.
>>>>>
>>>>> BTW, could you share the link of the relevant patches to mark this a no-op ?
>>>> Update changelog to make it clearer:
>>>>
>>>> The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was
>>>> removed as of v6.8-rc1, so it became a dead flag. And the series[1]
>>>> went on to mark it obsolete to avoid confusion for users. Here we
>>>> can just remove all its users, which has no functional change.
>>>>
>>>> [1] https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz/
>>> Thanks for your quick feedback.
>>>
>>> BTW, I couldn't find this change in Linus' tree in the master and even the v6.8-rc1 tag, please see https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/include/linux/slab.h?h=master.
>>>
>>> Did I miss something ? Or has this patch been merged ?
>> You're right, this patch hasn't been merged. But it's already a dead flag as of v6.8-rc1.
>>
>> Update changelog to make it clearer:
>>
>> The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was
>> removed as of v6.8-rc1, so it became a dead flag since the commit
>> 16a1d968358a ("mm/slab: remove mm/slab.c and slab_def.h"). And the
>> series[1] went on to mark it obsolete to avoid confusion for users.
>> Here we can just remove all its users, which has no functional change.
>>
>> [1] https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz/
>>
>> Does this look clearer to you? I can improve it if there is still confusion.
> 
> Yeah, much clearer, thanks!
> 
> Maybe we should just wait for the [1] to get merged first ?

It's really not necessary to wait, [1] just makes it explicit but the flag
is really effectively dead since v6.8-rc1 because nothing acts on it.