Re: [PATCH v7 0/9] mm: optimize zone-device memmap initialization

Andrew Morton <[email protected]> Mon, 20 Jul 2026 15:43:34 -0700

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 Mon, 20 Jul 2026 20:02:49 +0800 "Li Zhe" <[email protected]> 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/[email protected]