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From: Nathan Bossart <[email protected]>
Subject: [PATCH v2 5/9] convert PROC_HDR->startupBufferPinWaitBuf to an atomic
Date: Wed, 22 Jul 2026 11:32:57 -0400

---
 src/backend/storage/lmgr/proc.c | 12 +++---------
 src/include/storage/proc.h      |  2 +-
 2 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index f973494abb1..5be06073ea1 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -239,7 +239,7 @@ ProcGlobalShmemInit(void *arg)
 	dlist_init(&ProcGlobal->autovacFreeProcs);
 	dlist_init(&ProcGlobal->bgworkerFreeProcs);
 	dlist_init(&ProcGlobal->walsenderFreeProcs);
-	ProcGlobal->startupBufferPinWaitBuf = InvalidBuffer;
+	pg_atomic_init_u32(&ProcGlobal->startupBufferPinWaitBuf, InvalidBuffer);
 	pg_atomic_init_u32(&ProcGlobal->avLauncherProc, INVALID_PROC_NUMBER);
 	pg_atomic_init_u32(&ProcGlobal->walwriterProc, INVALID_PROC_NUMBER);
 	pg_atomic_init_u32(&ProcGlobal->checkpointerProc, INVALID_PROC_NUMBER);
@@ -768,10 +768,7 @@ InitAuxiliaryProcess(void)
 void
 SetStartupBufferPinWaitBuf(Buffer buffer)
 {
-	/* use volatile pointer to prevent code rearrangement */
-	volatile PROC_HDR *procglobal = ProcGlobal;
-
-	procglobal->startupBufferPinWaitBuf = buffer;
+	pg_atomic_write_u32(&ProcGlobal->startupBufferPinWaitBuf, buffer);
 }
 
 /*
@@ -780,10 +777,7 @@ SetStartupBufferPinWaitBuf(Buffer buffer)
 Buffer
 GetStartupBufferPinWaitBuf(void)
 {
-	/* use volatile pointer to prevent code rearrangement */
-	volatile PROC_HDR *procglobal = ProcGlobal;
-
-	return procglobal->startupBufferPinWaitBuf;
+	return pg_atomic_read_u32(&ProcGlobal->startupBufferPinWaitBuf);
 }
 
 /*
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h
index 4c3f431b4eb..abe40001d9a 100644
--- a/src/include/storage/proc.h
+++ b/src/include/storage/proc.h
@@ -500,7 +500,7 @@ typedef struct PROC_HDR
 	/* Current shared estimate of appropriate spins_per_delay value */
 	int			spins_per_delay;
 	/* Buffer that Startup process waits for pin on, or InvalidBuffer */
-	Buffer		startupBufferPinWaitBuf;
+	pg_atomic_uint32 startupBufferPinWaitBuf;
 } PROC_HDR;
 
 extern PGDLLIMPORT PROC_HDR *ProcGlobal;
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0006-convert-Sharedsort-currentWorker-workersFinished-.patch

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