v3-0001-Use-the-allocated-space-properly-for-custom-s-v18.patch

From f6787781026c7dcf6c9a38b0e7f8c8427a7b2da6 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Mon, 6 Apr 2026 09:47:02 +0900
Subject: [PATCH v3] Use the allocated space properly for custom stats kind

---
 src/backend/utils/activity/pgstat_shmem.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/backend/utils/activity/pgstat_shmem.c b/src/backend/utils/activity/pgstat_shmem.c
index 08ec264baa3a..2b7f783ef7c4 100644
--- a/src/backend/utils/activity/pgstat_shmem.c
+++ b/src/backend/utils/activity/pgstat_shmem.c
@@ -142,8 +142,7 @@ StatsShmemSize(void)
 			continue;
 
 		Assert(kind_info->shared_size != 0);
-
-		sz += MAXALIGN(kind_info->shared_size);
+		sz = add_size(sz, MAXALIGN(kind_info->shared_size));
 	}
 
 	return sz;
@@ -227,7 +226,8 @@ StatsShmemInit(void)
 				int			idx = kind - PGSTAT_KIND_CUSTOM_MIN;
 
 				Assert(kind_info->shared_size != 0);
-				ctl->custom_data[idx] = ShmemAlloc(kind_info->shared_size);
+				ctl->custom_data[idx] = p;
+				p += MAXALIGN(kind_info->shared_size);
 				ptr = ctl->custom_data[idx];
 			}
 
-- 
2.53.0