From: Nathan Bossart <nathan@postgresql.org>
Date: Mon, 23 Feb 2026 21:32:01 +0000 (-0600)
Subject: Convert SpinLock* macros to static inline functions.
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=bfc321b4723e8ca5fd3adb22a2727ec5c55d3808;p=thirdparty%2Fpostgresql.git

Convert SpinLock* macros to static inline functions.

This is preparatory work for a proposed follow-up commit that would
add assertions to these functions.

Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/aZX2oUcKf7IzHnnK%40nathan
Discussion: https://postgr.es/m/20200617183354.pm3biu3zbmo2pktq%40alap3.anarazel.de
---

diff --git a/src/include/storage/spin.h b/src/include/storage/spin.h
index 78c95ae538b..9cf6adb671a 100644
--- a/src/include/storage/spin.h
+++ b/src/include/storage/spin.h
@@ -5,7 +5,7 @@
  *
  *
  *	The interface to spinlocks is defined by the typedef "slock_t" and
- *	these macros:
+ *	these functions:
  *
  *	void SpinLockInit(volatile slock_t *lock)
  *		Initialize a spinlock (to the unlocked state).
@@ -18,9 +18,6 @@
  *	void SpinLockRelease(volatile slock_t *lock)
  *		Unlock a previously acquired lock.
  *
- *	Callers must beware that the macro argument may be evaluated multiple
- *	times!
- *
  *	Load and store operations in calling code are guaranteed not to be
  *	reordered with respect to these operations, because they include a
  *	compiler barrier.  (Before PostgreSQL 9.5, callers needed to use a
@@ -29,9 +26,9 @@
  *	Keep in mind the coding rule that spinlocks must not be held for more
  *	than a few instructions.  In particular, we assume it is not possible
  *	for a CHECK_FOR_INTERRUPTS() to occur while holding a spinlock, and so
- *	it is not necessary to do HOLD/RESUME_INTERRUPTS() in these macros.
+ *	it is not necessary to do HOLD/RESUME_INTERRUPTS() in these functions.
  *
- *	These macros are implemented in terms of hardware-dependent macros
+ *	These functions are implemented in terms of hardware-dependent macros
  *	supplied by s_lock.h.  There is not currently any extra functionality
  *	added by this header, but there has been in the past and may someday
  *	be again.
@@ -49,11 +46,22 @@
 
 #include "storage/s_lock.h"
 
+static inline void
+SpinLockInit(volatile slock_t *lock)
+{
+	S_INIT_LOCK(lock);
+}
 
-#define SpinLockInit(lock)	S_INIT_LOCK(lock)
-
-#define SpinLockAcquire(lock) S_LOCK(lock)
+static inline void
+SpinLockAcquire(volatile slock_t *lock)
+{
+	S_LOCK(lock);
+}
 
-#define SpinLockRelease(lock) S_UNLOCK(lock)
+static inline void
+SpinLockRelease(volatile slock_t *lock)
+{
+	S_UNLOCK(lock);
+}
 
 #endif							/* SPIN_H */