patch-2.1.92 linux/include/asm-alpha/spinlock.h

• Lines: 211
• Date: Mon Mar 30 00:21:41 1998
• Orig file: v2.1.91/linux/include/asm-alpha/spinlock.h
• Orig date: Tue May 13 22:41:17 1997

diff -u --recursive --new-file v2.1.91/linux/include/asm-alpha/spinlock.h linux/include/asm-alpha/spinlock.h
@@ -45,7 +45,10 @@
 #define write_lock_irqsave(lock, flags)		do { (flags) = swpipl(7); } while (0)
 #define write_unlock_irqrestore(lock, flags)	setipl(flags)
 
-#else
+#else /* __SMP__ */
+
+#include <linux/kernel.h>
+#include <asm/current.h>
 
 /* Simple spin lock operations.  There are two variants, one clears IRQ's
  * on the local processor, one does not.
@@ -56,12 +59,15 @@
 typedef struct {
 	volatile unsigned long lock;
 	unsigned long previous;
+	unsigned long task;
 } spinlock_t;
 
 #define SPIN_LOCK_UNLOCKED { 0, 0 }
 
-#define spin_lock_init(lock)	do { (lock)->lock = 0; (lock)->previous = 0; } while(0)
-#define spin_unlock_wait(lock)	do { barrier(); } while(((volatile spinlock_t *)lock)->lock)
+#define spin_lock_init(x) \
+	do { (x)->lock = 0; (x)->previous = 0; } while(0)
+#define spin_unlock_wait(x) \
+	do { barrier(); } while(((volatile spinlock_t *)x)->lock)
 
 typedef struct { unsigned long a[100]; } __dummy_lock_t;
 #define __dummy_lock(lock) (*(__dummy_lock_t *)(lock))
@@ -73,40 +79,38 @@
 	:"=m" (__dummy_lock(lock)));
 }
 
+#if 1
+#define DEBUG_SPINLOCK
+#else
+#undef DEBUG_SPINLOCK
+#endif
+
+#ifdef DEBUG_SPINLOCK
+extern void spin_lock(spinlock_t * lock);
+#else
 static inline void spin_lock(spinlock_t * lock)
 {
-	__label__ l1;
 	long tmp;
-	long stuck = 0x100000000;
-l1:
+
 	/* Use sub-sections to put the actual loop at the end
 	   of this object file's text section so as to perfect
 	   branch prediction.  */
 	__asm__ __volatile__(
 	"1:	ldq_l	%0,%1\n"
-	"	subq	%2,1,%2\n"
 	"	blbs	%0,2f\n"
 	"	or	%0,1,%0\n"
 	"	stq_c	%0,%1\n"
-	"	beq	%0,3f\n"
+	"	beq	%0,2f\n"
 	"4:	mb\n"
 	".section .text2,\"ax\"\n"
 	"2:	ldq	%0,%1\n"
-	"	subq	%2,1,%2\n"
-	"3:	blt	%2,4b\n"
 	"	blbs	%0,2b\n"
 	"	br	1b\n"
 	".previous"
 	: "=r" (tmp),
-	  "=m" (__dummy_lock(lock)),
-	  "=r" (stuck)
-	: "2" (stuck));
-
-	if (stuck < 0)
-		printk("spinlock stuck at %p (%lx)\n",&&l1,lock->previous);
-	else
-		lock->previous = (unsigned long) &&l1;
+	  "=m" (__dummy_lock(lock)));
 }
+#endif /* DEBUG_SPINLOCK */
 
 #define spin_trylock(lock) (!test_and_set_bit(0,(lock)))
 
@@ -117,10 +121,124 @@
 	do { spin_unlock(lock); __sti(); } while (0)
 
 #define spin_lock_irqsave(lock, flags) \
-	do { flags = swpipl(7); spin_lock(lock); } while (0)
+	do { __save_and_cli(flags); spin_lock(lock); } while (0)
 
 #define spin_unlock_irqrestore(lock, flags) \
-	do { spin_unlock(lock); setipl(flags); } while (0)
+	do { spin_unlock(lock); __restore_flags(flags); } while (0)
+
+/***********************************************************/
+
+#if 1
+#define DEBUG_RWLOCK
+#else
+#undef DEBUG_RWLOCK
+#endif
+
+typedef struct { volatile int write_lock:1, read_counter:31; } rwlock_t;
+
+#define RW_LOCK_UNLOCKED { 0, 0 }
+
+#ifdef DEBUG_RWLOCK
+extern void write_lock(rwlock_t * lock);
+#else
+static inline void write_lock(rwlock_t * lock)
+{
+	long regx, regy;
+
+	__asm__ __volatile__(
+	"1:	ldl_l	%1,%0;"
+	"	blbs	%1,6f;"
+	"	or	%1,1,%2;"
+	"	stl_c	%2,%0;"
+	"	beq	%2,6f;"
+	"	blt	%1,8f;"
+	"4:	mb\n"
+	".section .text2,\"ax\"\n"
+	"6:	ldl	%1,%0;"
+	"	blbs	%1,6b;"
+	"	br	1b;"
+	"8:	ldl	%1,%0;"
+	"	blt	%1,8b;"
+	"9:	br	4b\n"
+	".previous"
+	: "=m" (__dummy_lock(lock)), "=&r" (regx), "=&r" (regy)
+	: "0" (__dummy_lock(lock))
+	);
+}
+#endif /* DEBUG_RWLOCK */
+
+static inline void write_unlock(rwlock_t * lock)
+{
+	__asm__ __volatile__("mb; stl $31,%0" : "=m" (__dummy_lock(lock)));
+}
+
+#ifdef DEBUG_RWLOCK
+extern void _read_lock(rwlock_t * lock);
+#else
+static inline void _read_lock(rwlock_t * lock)
+{
+	long regx;
+
+	__asm__ __volatile__(
+	"1:	ldl_l	%1,%0;"
+	"	blbs	%1,6f;"
+	"	subl	%1,2,%1;"
+	"	stl_c	%1,%0;"
+	"	beq	%1,6f;"
+	"4:	mb\n"
+	".section .text2,\"ax\"\n"
+	"6:	ldl	%1,%0;"
+	"	blbs	%1,6b;"
+	"	br	1b\n"
+	".previous"
+	: "=m" (__dummy_lock(lock)), "=&r" (regx)
+	: "0" (__dummy_lock(lock))
+	);
+}
+#endif /* DEBUG_RWLOCK */
+
+#define read_lock(lock) \
+do {	unsigned long flags; \
+	__save_and_cli(flags); \
+	_read_lock(lock); \
+	__restore_flags(flags); \
+} while(0)
+
+static inline void _read_unlock(rwlock_t * lock)
+{
+	long regx;
+	__asm__ __volatile__(
+	"1:	ldl_l	%1,%0;"
+	"	addl	%1,2,%1;"
+	"	stl_c	%1,%0;"
+	"	beq	%1,6f;"
+	".section .text2,\"ax\"\n"
+	"6:	br	1b\n"
+	".previous"
+	: "=m" (__dummy_lock(lock)), "=&r" (regx)
+	: "0" (__dummy_lock(lock)));
+}
+
+#define read_unlock(lock) \
+do {	unsigned long flags; \
+	__save_and_cli(flags); \
+	_read_unlock(lock); \
+	__restore_flags(flags); \
+} while(0)
+
+#define read_lock_irq(lock)	do { __cli(); _read_lock(lock); } while (0)
+#define read_unlock_irq(lock)	do { _read_unlock(lock); __sti(); } while (0)
+#define write_lock_irq(lock)	do { __cli(); write_lock(lock); } while (0)
+#define write_unlock_irq(lock)	do { write_unlock(lock); __sti(); } while (0)
+
+#define read_lock_irqsave(lock, flags)	\
+	do { __save_and_cli(flags); _read_lock(lock); } while (0)
+#define read_unlock_irqrestore(lock, flags) \
+	do { _read_unlock(lock); __restore_flags(flags); } while (0)
+#define write_lock_irqsave(lock, flags)	\
+	do { __save_and_cli(flags); write_lock(lock); } while (0)
+#define write_unlock_irqrestore(lock, flags) \
+	do { write_unlock(lock); __restore_flags(flags); } while (0)
 
 #endif /* SMP */
 #endif /* _ALPHA_SPINLOCK_H */