+ mm-vmstat-output-reserved_highatomic-and-free_highatomic-in-zoneinfo.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: vmstat: output reserved_highatomic and free_highatomic in zoneinfo
has been added to the -mm mm-new branch.  Its filename is
     mm-vmstat-output-reserved_highatomic-and-free_highatomic-in-zoneinfo.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmstat-output-reserved_highatomic-and-free_highatomic-in-zoneinfo.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
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------------------------------------------------------
From: Jiayuan Chen <jiayuan.chen@linux.dev>
Subject: mm: vmstat: output reserved_highatomic and free_highatomic in zoneinfo
Date: Mon, 27 Oct 2025 22:18:17 +0800

The nr_free_highatomic is a key factor in calculating watermarks as it
affects the free pages count.  Adding this metric, along with
nr_reserved_highatomic, to /proc/zoneinfo facilitates easier diagnosis
memory watermark calculations and memory pressure states.

Sample output:
cat /proc/zoneinfo
......
pagesets
cpu: 0
		  count:    52069
		  high:     52675
		  batch:    63
		  high_min: 13971
		  high_max: 62284
vm stats threshold: 10
node_unreclaimable:  0
start_pfn:           4096
reserved_highatomic: 5120
free_highatomic:     2081

Link: https://lkml.kernel.org/r/20251027141818.283587-1-jiayuan.chen@linux.dev
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmstat.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/mm/vmstat.c~mm-vmstat-output-reserved_highatomic-and-free_highatomic-in-zoneinfo
+++ a/mm/vmstat.c
@@ -1852,9 +1852,13 @@ static void zoneinfo_show_print(struct s
 	}
 	seq_printf(m,
 		   "\n  node_unreclaimable:  %u"
-		   "\n  start_pfn:           %lu",
+		   "\n  start_pfn:           %lu"
+		   "\n  reserved_highatomic: %lu"
+		   "\n  free_highatomic:     %lu",
 		   atomic_read(&pgdat->kswapd_failures) >= MAX_RECLAIM_RETRIES,
-		   zone->zone_start_pfn);
+		   zone->zone_start_pfn,
+		   zone->nr_reserved_highatomic,
+		   zone->nr_free_highatomic);
 	seq_putc(m, '\n');
 }
 
_

Patches currently in -mm which might be from jiayuan.chen@linux.dev are

mm-vmscan-skip-increasing-kswapd_failures-when-reclaim-was-boosted.patch
mm-vmstat-output-reserved_highatomic-and-free_highatomic-in-zoneinfo.patch