From: Andrew Morton <akpm@linux-foundation.org>
To: Sang-Heon Jeon <ekffu200098@gmail.com>
Cc: Mike Rapoport <rppt@kernel.org>, linux-mm@kvack.org
Subject: Re: [PATCH] mm/mm_init: remove unnecessary initialization of pgdat->per_cpu_nodestats
Date: Wed, 29 Jul 2026 13:27:45 -0700 [thread overview]
Message-ID: <20260729132745.9d42a13e614be2e18c5988ba@linux-foundation.org> (raw)
In-Reply-To: <20260729155143.177790-1-ekffu200098@gmail.com>
On Thu, 30 Jul 2026 00:51:15 +0900 Sang-Heon Jeon <ekffu200098@gmail.com> wrote:
> free_area_init_node() sets pgdat->per_cpu_nodestats to NULL and later
> calls free_area_init_core(), which unconditionally overwrites it with
> &boot_nodestats. Nothing reads the field in between, so the store has
> no effect.
>
> Remove unnecessary initialization. No functional change.
>
> ...
>
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -1722,7 +1722,6 @@ static void __init free_area_init_node(int nid)
>
> pgdat->node_id = nid;
> pgdat->node_start_pfn = start_pfn;
> - pgdat->per_cpu_nodestats = NULL;
>
> if (start_pfn != end_pfn) {
> pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid,
Looks OK, thanks. Although this statement is "free" in __init code and
its removal does make the code that bit harder to follow.
Possibly *pgdat was zeroed out anyway, I got bored figuring that out.
The memblock_alloc_range_nid() kerneldoc is silent on the state of the
returned memory but I spy a kzalloc_node() in there.
next prev parent reply other threads:[~2026-07-29 20:27 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-29 15:51 [PATCH] mm/mm_init: remove unnecessary initialization of pgdat->per_cpu_nodestats Sang-Heon Jeon
2026-07-29 20:27 ` Andrew Morton [this message]
2026-07-30 6:58 ` Mike Rapoport
2026-07-30 7:06 ` Mike Rapoport
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