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Date: Mon, 20 Jul 2026 15:43:34 -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>, <rppt@kernel.org>,
 <tglx@kernel.org>, <muchun.song@linux.dev>, <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 v7 0/9] mm: optimize zone-device memmap initialization
Message-Id: <20260720154334.b619e7b436d2dc2481b233ea@linux-foundation.org>
In-Reply-To: <20260720120259.1545-1-lizhe.67@bytedance.com>
References: <20260720120259.1545-1-lizhe.67@bytedance.com>
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On Mon, 20 Jul 2026 20:02:49 +0800 "Li Zhe" <lizhe.67@bytedance.com> wrote:

> memmap_init_zone_device() can take a noticeable amount of time when large
> pmem namespaces are bound or rebound, because it initializes nearly
> identical struct page descriptors one PFN at a time. This series reduces
> that ZONE_DEVICE memmap initialization overhead by reusing prepared
> struct page templates and, on x86, using memcpy_nontemporal() for the
> template copy path.

What Dave said - more details on the real-world userspace benefit would
be helpful, thanks.

AI review might have found some things, one "critical":
	https://sashiko.dev/#/patchset/20260720120259.1545-1-lizhe.67@bytedance.com