Re: [PATCH v9 0/8] mm: optimize zone-device memmap initialization

"Li Zhe" <[email protected]> Wed, 5 Aug 2026 17:49:22 +0800
Newsgroups org.kernel.vger.linux-arch,org.kernel.vger.linux-hardening,org.kernel.vger.linux-kernel,org.kvack.linux-mm
Message-ID <[email protected]>
On 8/4/26 5:40 AM, Andrew Morton wrote:
> On Mon,  3 Aug 2026 15:09:21 +0800 "Li Zhe" <[email protected]> wrote:
>
>> Test procedure:
>> Rebind the nd_pmem and dax_pmem drivers 30 times and collect the memmap
>> initialization time from the pr_debug() output of
>> memmap_init_zone_device().
>>
>> Base(v7.2-rc1):
>>    Average of nd_pmem rebinds: 244.28 ms
>>    Average of dax_pmem rebinds: 273.31 ms
>>
>> With this series applied:
>>    Average of nd_pmem rebinds: 96.79 ms
>>    Average of dax_pmem rebinds: 119.04 ms
>>
>> This reduces the average memmap initialization time measured during
>> rebind by about 60.4% for nd_pmem and 56.4% for dax_pmem.
> Well that's nice.
>
> Review is partial and it's late in the cycle so I'd prefer to schedule
> this for the next -rc cycle.
>
> AI review might have found a couple of things, please check?
> 	https://sashiko.dev/#/patchset/[email protected]


Thanks.

I checked the Sashiko comments. The reported items are the same points
that were discussed in the previous v7/v8 reviews. v9 already folds the
related explanation into patch 7, so I do not plan any additional code
change for these items.

Thanks,
Zhe