Make init_spin_delay() C89 compliant #2.

anarazel · anarazel · commit 4b74c6a40e7a · 2016-04-14T19:26:13.000-07:00
My previous attempt at doing so, in 80abbeb, was not sufficient. While that fixed the problem for bufmgr.c and lwlock.c , s_lock.c still has non-constant expressions in the struct initializer, because the file/line/function information comes from the caller of s_lock(). Give up on using a macro, and use a static inline instead. Discussion: 4369.1460435533@sss.pgh.pa.us
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
@@ -4029,9 +4029,11 @@ rnode_comparator(const void *p1, const void *p2)
 uint32
 LockBufHdr(BufferDesc *desc)
 {
-	SpinDelayStatus delayStatus = init_local_spin_delay();
+	SpinDelayStatus delayStatus;
 	uint32		old_buf_state;
 
+	init_local_spin_delay(&delayStatus);
+
 	while (true)
 	{
 		/* set BM_LOCKED flag */
@@ -4055,9 +4057,11 @@ LockBufHdr(BufferDesc *desc)
 static uint32
 WaitBufHdrUnlocked(BufferDesc *buf)
 {
-	SpinDelayStatus delayStatus = init_local_spin_delay();
+	SpinDelayStatus delayStatus;
 	uint32		buf_state;
 
+	init_local_spin_delay(&delayStatus);
+
 	buf_state = pg_atomic_read_u32(&buf->state);
 
 	while (buf_state & BM_LOCKED)
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
@@ -870,7 +870,9 @@ LWLockWaitListLock(LWLock *lock)
 
 		/* and then spin without atomic operations until lock is released */
 		{
-			SpinDelayStatus delayStatus = init_local_spin_delay();
+			SpinDelayStatus delayStatus;
+
+			init_local_spin_delay(&delayStatus);
 
 			while (old_state & LW_FLAG_LOCKED)
 			{
diff --git a/src/backend/storage/lmgr/s_lock.c b/src/backend/storage/lmgr/s_lock.c
@@ -91,7 +91,9 @@ s_lock_stuck(const char *file, int line, const char *func)
 int
 s_lock(volatile slock_t *lock, const char *file, int line, const char *func)
 {
-	SpinDelayStatus delayStatus = init_spin_delay(file, line, func);
+	SpinDelayStatus delayStatus;
+
+	init_spin_delay(&delayStatus, file, line, func);
 
 	while (TAS_SPIN(lock))
 	{
diff --git a/src/include/storage/s_lock.h b/src/include/storage/s_lock.h
@@ -1005,8 +1005,19 @@ typedef struct
 	const char *func;
 } SpinDelayStatus;
 
-#define init_spin_delay(file, line, func) {0, 0, 0, file, line, func}
-#define init_local_spin_delay() init_spin_delay(__FILE__, __LINE__, PG_FUNCNAME_MACRO)
+static inline void
+init_spin_delay(SpinDelayStatus *status,
+				const char *file, int line, const char *func)
+{
+	status->spins = 0;
+	status->delays = 0;
+	status->cur_delay = 0;
+	status->file = file;
+	status->line = line;
+	status->func = func;
+}
+
+#define init_local_spin_delay(status) init_spin_delay(status, __FILE__, __LINE__, PG_FUNCNAME_MACRO)
 void perform_spin_delay(SpinDelayStatus *status);
 void finish_spin_delay(SpinDelayStatus *status);
 

Original file line number	Diff line number	Diff line change
`@@ -870,7 +870,9 @@ LWLockWaitListLock(LWLock *lock)`
`870`	`870`
`871`	`871`	`/* and then spin without atomic operations until lock is released */`
`872`	`872`	`{`
`873`		`- SpinDelayStatus delayStatus = init_local_spin_delay();`
	`873`	`+ SpinDelayStatus delayStatus;`
	`874`	`+`
	`875`	`+ init_local_spin_delay(&delayStatus);`
`874`	`876`
`875`	`877`	`while (old_state & LW_FLAG_LOCKED)`
`876`	`878`	`{`
Original file line number	Diff line number	Diff line change
`@@ -91,7 +91,9 @@ s_lock_stuck(const char file, int line, const char func)`
`91`	`91`	`int`
`92`	`92`	`s_lock(volatile slock_t lock, const char file, int line, const char *func)`
`93`	`93`	`{`
`94`		`- SpinDelayStatus delayStatus = init_spin_delay(file, line, func);`
	`94`	`+ SpinDelayStatus delayStatus;`
	`95`	`+`
	`96`	`+ init_spin_delay(&delayStatus, file, line, func);`
`95`	`97`
`96`	`98`	`while (TAS_SPIN(lock))`
`97`	`99`	`{`