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Date: Mon, 3 Aug 2026 14:40:14 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: "Li Zhe" <lizhe.67@bytedance.com>
Cc: <apopple@nvidia.com>, <arnd@arndb.de>, <balbirs@nvidia.com>,
 <bp@alien8.de>, <dave.hansen@linux.intel.com>, <david@kernel.org>,
 <kees@kernel.org>, <mingo@redhat.com>, <muchun.song@linux.dev>,
 <rppt@kernel.org>, <tglx@kernel.org>, <linux-arch@vger.kernel.org>,
 <linux-hardening@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
 <linux-mm@kvack.org>, <x86@kernel.org>
Subject: Re: [PATCH v9 0/8] mm: optimize zone-device memmap initialization
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On Mon,  3 Aug 2026 15:09:21 +0800 "Li Zhe" <lizhe.67@bytedance.com> 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/20260803070929.86075-1-lizhe.67@bytedance.com