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Date:   Tue, 14 Jun 2022 10:38:01 +0800
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Subject: Re: [PATCH 1/3] mm/slub: fix the race between validate_slab and
 slab_free
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To:     Christoph Lameter <cl@gentwo.de>, penberg@kernel.org
Cc:     David Rientjes <rientjes@google.com>, songmuchun@bytedance.com,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>, akpm@linux-foundation.org,
        vbabka@suse.cz, roman.gushchin@linux.dev, iamjoonsoo.kim@lge.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
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From:   Rongwei Wang <rongwei.wang@linux.alibaba.com>
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On 6/13/22 9:50 PM, Christoph Lameter wrote:
> On Sat, 11 Jun 2022, Rongwei Wang wrote:
> 
>>> Ok so the idea is to take the lock only if kmem_cache_debug. That looks
>>> ok. But it still adds a number of new branches etc to the free loop.
>>>
>>> Some performance tests would be useful.
>> Hi Christoph
>>
>> Thanks for your time!
>> Do you have some advice in benchmarks that need me to test? And I find that
>> hackbench and lkp was used frequently in mm/slub.c commits[1,2]. But I have no
>> idea how to use these two benchmarks test to cover the above changes. Can you
>> give some examples? Thanks very much!
> 
> 
> Hi Rongwei,
> 
> Well run hackbench with an without the change.
OK
> 
> There are also synthetic benchmarks available  at
> https://gentwo.org/christoph/slub/tests/
That's great, thanks very much!
> 
> These measure the cycles that slab operations take. However, they are a
> bit old and I think Pekka may have a newer version of these
> patches.
> 
> Greetings,
> 	Christoph