Back-port recent MIPS and M68K spinlock improvements to 8.0 branch.

src/backend/storage/lmgr/s_lock.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/s_lock.c,v 1.35 2004/12/31 22:01:05 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/s_lock.c,v 1.35.4.1 2005/08/26 14:48:13 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -135,7 +135,12 @@ s_lock(volatile slock_t *lock, const char *file, int line)
  */
 
 
-#if defined(__m68k__)
+/*
+ * Note: all the if-tests here probably ought to be testing gcc version
+ * rather than platform, but I don't have adequate info to know what to
+ * write.  Ideally we'd flush all this in favor of the inline version.
+ */
+#if defined(__m68k__) && !defined(__linux__)
 /* really means: extern int tas(slock_t* **lock); */
 static void
 tas_dummy()
@@ -169,35 +174,7 @@ _success:						\n\
 #endif   /* __NetBSD__ && __ELF__ */
 );
 }
-#endif   /* __m68k__ */
+#endif   /* __m68k__ && !__linux__ */
-
-
-#if defined(__mips__) && !defined(__sgi)
-static void
-tas_dummy()
-{
-	__asm__		__volatile__(
-										 "\
-.global	tas						\n\
-tas:							\n\
-			.frame	$sp, 0, $31	\n\
-			.set push		\n\
-			.set mips2		\n\
-			ll		$14, 0($4)	\n\
-			or		$15, $14, 1	\n\
-			sc		$15, 0($4)	\n\
-			.set pop			\n\
-			beq		$15, 0, fail\n\
-			bne		$14, 0, fail\n\
-			li		$2, 0		\n\
-			.livereg 0x2000FF0E,0x00000FFF	\n\
-			j		$31			\n\
-fail:							\n\
-			li		$2, 1		\n\
-			j   	$31			\n\
-");
-}
-#endif   /* __mips__ && !__sgi */
 
 
 #else							/* not __GNUC__ */

src/include/storage/s_lock.h

@@ -66,7 +66,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	  $PostgreSQL: pgsql/src/include/storage/s_lock.h,v 1.133 2004/12/31 22:03:42 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/include/storage/s_lock.h,v 1.133.4.1 2005/08/26 14:48:13 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -313,7 +313,7 @@ do \
 #endif /* powerpc */
 
 
-#if defined(__mc68000__) && defined(__linux__)
+#if (defined(__mc68000__) || defined(__m68k__)) && defined(__linux__)
 #define HAS_TEST_AND_SET
 
 typedef unsigned char slock_t;
@@ -335,7 +335,7 @@ tas(volatile slock_t *lock)
 	return rv;
 }
 
-#endif	 /* defined(__mc68000__) && defined(__linux__) */
+#endif	 /* (__mc68000__ || __m68k__) && __linux__ */
 
 
 #if defined(__vax__)
@@ -438,20 +438,48 @@ do \
 #endif /* __alpha || __alpha__ */
 
 
-/* These live in s_lock.c, but only for gcc */
-
-
-#if defined(__m68k__)
-#define HAS_TEST_AND_SET
-
-typedef unsigned char slock_t;
-#endif
-
-
 #if defined(__mips__) && !defined(__sgi)
+/* Note: on SGI we use the OS' mutex ABI, see below */
 #define HAS_TEST_AND_SET
 
 typedef unsigned int slock_t;
+
+#define TAS(lock) tas(lock)
+
+static __inline__ int
+tas(volatile slock_t *lock)
+{
+	register volatile slock_t *__l = lock;
+	register int __r;
+
+	__asm__ __volatile__(
+		"       .set push           \n"
+		"       .set mips2          \n"
+		"       .set noreorder      \n"
+		"       .set nomacro        \n"
+		"1:     ll      %0, %1      \n"
+		"       bne     %0, $0, 1f  \n"
+		"        xori   %0, 1       \n"
+		"       sc      %0, %1      \n"
+		"       beq     %0, $0, 1b  \n"
+		"        sync               \n"
+		"1:     .set pop              "
+:		"=&r" (__r), "+R" (*__l)
+:
+:		"memory", "cc");
+	return __r;
+}
+
+#endif /* __mips__ && !__sgi */
+
+
+/* These live in s_lock.c, but only for gcc */
+
+
+#if defined(__m68k__) && !defined(__linux__)
+#define HAS_TEST_AND_SET
+
+typedef unsigned char slock_t;
 #endif