0008-Replace-ProcSendSignal-ProcWaitForSignal-with-new-in.patch

From 9e704efaff17e7829b6913f55213e8347df85d9b Mon Sep 17 00:00:00 2001
From: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Date: Sat, 24 Aug 2024 00:58:05 +0300
Subject: [PATCH 08/11] Replace ProcSendSignal/ProcWaitForSignal with new
 interrupt functions

---
 src/backend/storage/buffer/bufmgr.c  |  5 +++--
 src/backend/storage/ipc/standby.c    |  9 ++++++---
 src/backend/storage/lmgr/predicate.c |  5 +++--
 src/backend/storage/lmgr/proc.c      | 28 ----------------------------
 src/include/storage/proc.h           |  3 ---
 5 files changed, 12 insertions(+), 38 deletions(-)

diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index fb38c7bdd4..3e335b0944 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -2891,7 +2891,7 @@ UnpinBufferNoOwner(BufferDesc *buf)
 
 				buf_state &= ~BM_PIN_COUNT_WAITER;
 				UnlockBufHdr(buf, buf_state);
-				ProcSendSignal(wait_backend_pgprocno);
+				SendInterrupt(INTERRUPT_GENERAL_WAKEUP, wait_backend_pgprocno);
 			}
 			else
 				UnlockBufHdr(buf, buf_state);
@@ -5353,7 +5353,8 @@ LockBufferForCleanup(Buffer buffer)
 			SetStartupBufferPinWaitBufId(-1);
 		}
 		else
-			ProcWaitForSignal(WAIT_EVENT_BUFFER_PIN);
+			WaitInterrupt(1 << INTERRUPT_GENERAL_WAKEUP, WL_INTERRUPT | WL_EXIT_ON_PM_DEATH, 0,
+						  WAIT_EVENT_BUFFER_PIN);
 
 		/*
 		 * Remove flag marking us as waiter. Normally this will not be set
diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index 872679ca44..437b13da90 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -696,7 +696,8 @@ ResolveRecoveryConflictWithLock(LOCKTAG locktag, bool logging_conflict)
 	}
 
 	/* Wait to be signaled by the release of the Relation Lock */
-	ProcWaitForSignal(PG_WAIT_LOCK | locktag.locktag_type);
+	WaitInterrupt(1 << INTERRUPT_GENERAL_WAKEUP, WL_INTERRUPT | WL_EXIT_ON_PM_DEATH, 0,
+				  PG_WAIT_LOCK | locktag.locktag_type);
 
 	/*
 	 * Exit if ltime is reached. Then all the backends holding conflicting
@@ -745,7 +746,8 @@ ResolveRecoveryConflictWithLock(LOCKTAG locktag, bool logging_conflict)
 		 * until the relation locks are released or ltime is reached.
 		 */
 		got_standby_deadlock_timeout = false;
-		ProcWaitForSignal(PG_WAIT_LOCK | locktag.locktag_type);
+		WaitInterrupt(1 << INTERRUPT_GENERAL_WAKEUP, WL_INTERRUPT | WL_EXIT_ON_PM_DEATH, 0,
+					  PG_WAIT_LOCK | locktag.locktag_type);
 	}
 
 cleanup:
@@ -839,7 +841,8 @@ ResolveRecoveryConflictWithBufferPin(void)
 	 * SIGHUP signal handler, etc cannot do that because it uses the different
 	 * latch from that ProcWaitForSignal() waits on.
 	 */
-	ProcWaitForSignal(WAIT_EVENT_BUFFER_PIN);
+	WaitInterrupt(1 << INTERRUPT_GENERAL_WAKEUP, WL_INTERRUPT | WL_EXIT_ON_PM_DEATH, 0,
+				  WAIT_EVENT_BUFFER_PIN);
 
 	if (got_standby_delay_timeout)
 		SendRecoveryConflictWithBufferPin(PROCSIG_RECOVERY_CONFLICT_BUFFERPIN);
diff --git a/src/backend/storage/lmgr/predicate.c b/src/backend/storage/lmgr/predicate.c
index b455b78f9f..f0234269b6 100644
--- a/src/backend/storage/lmgr/predicate.c
+++ b/src/backend/storage/lmgr/predicate.c
@@ -1571,7 +1571,8 @@ GetSafeSnapshot(Snapshot origSnapshot)
 				 SxactIsROUnsafe(MySerializableXact)))
 		{
 			LWLockRelease(SerializableXactHashLock);
-			ProcWaitForSignal(WAIT_EVENT_SAFE_SNAPSHOT);
+			WaitInterrupt(1 << INTERRUPT_GENERAL_WAKEUP, WL_INTERRUPT | WL_EXIT_ON_PM_DEATH, 0,
+						  WAIT_EVENT_SAFE_SNAPSHOT);
 			LWLockAcquire(SerializableXactHashLock, LW_EXCLUSIVE);
 		}
 		MySerializableXact->flags &= ~SXACT_FLAG_DEFERRABLE_WAITING;
@@ -3604,7 +3605,7 @@ ReleasePredicateLocks(bool isCommit, bool isReadOnlySafe)
 			 */
 			if (SxactIsDeferrableWaiting(roXact) &&
 				(SxactIsROUnsafe(roXact) || SxactIsROSafe(roXact)))
-				ProcSendSignal(roXact->pgprocno);
+				SendInterrupt(INTERRUPT_GENERAL_WAKEUP, roXact->pgprocno);
 		}
 	}
 
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index f4fe4e873f..a7c258fd17 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -1866,34 +1866,6 @@ CheckDeadLockAlert(void)
 	errno = save_errno;
 }
 
-/*
- * ProcWaitForSignal - wait for a signal from another backend.
- *
- * As this uses the generic process interurpt the caller has to be robust against
- * unrelated wakeups: Always check that the desired state has occurred, and
- * wait again if not.
- */
-void
-ProcWaitForSignal(uint32 wait_event_info)
-{
-	(void) WaitInterrupt(1 << INTERRUPT_GENERAL_WAKEUP, WL_INTERRUPT | WL_EXIT_ON_PM_DEATH, 0,
-						 wait_event_info);
-	ClearInterrupt(INTERRUPT_GENERAL_WAKEUP);
-	CHECK_FOR_INTERRUPTS();
-}
-
-/*
- * ProcSendSignal - send the interrupt of a backend identified by ProcNumber
- */
-void
-ProcSendSignal(ProcNumber procNumber)
-{
-	if (procNumber < 0 || procNumber >= ProcGlobal->allProcCount)
-		elog(ERROR, "procNumber out of range");
-
-	SendInterrupt(INTERRUPT_GENERAL_WAKEUP, procNumber);
-}
-
 /*
  * BecomeLockGroupLeader - designate process as lock group leader
  *
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h
index d0ed28315a..1ef39d8754 100644
--- a/src/include/storage/proc.h
+++ b/src/include/storage/proc.h
@@ -510,9 +510,6 @@ extern void CheckDeadLockAlert(void);
 extern bool IsWaitingForLock(void);
 extern void LockErrorCleanup(void);
 
-extern void ProcWaitForSignal(uint32 wait_event_info);
-extern void ProcSendSignal(ProcNumber procNumber);
-
 extern PGPROC *AuxiliaryPidGetProc(int pid);
 
 extern void BecomeLockGroupLeader(void);
-- 
2.39.2