patch-2.2.8 linux/include/asm-m68k/semaphore.h

• Lines: 163
• Date: Tue May 11 09:57:14 1999
• Orig file: v2.2.7/linux/include/asm-m68k/semaphore.h
• Orig date: Wed Jan 20 23:14:06 1999

diff -u --recursive --new-file v2.2.7/linux/include/asm-m68k/semaphore.h linux/include/asm-m68k/semaphore.h
@@ -3,9 +3,10 @@
 
 #include <linux/config.h>
 #include <linux/linkage.h>
-#include <asm/current.h>
+
 #include <asm/system.h>
 #include <asm/atomic.h>
+#include <asm/spinlock.h>
 
 /*
  * SMP- and interrupt-safe semaphores..
@@ -17,79 +18,25 @@
 
 struct semaphore {
 	atomic_t count;
-	unsigned long owner, owner_depth;
 	atomic_t waking;
 	struct wait_queue * wait;
 };
 
-/*
- * Because we want the non-contention case to be
- * fast, we save the stack pointer into the "owner"
- * field, and to get the true task pointer we have
- * to do the bit masking. That moves the masking
- * operation into the slow path.
- */
-#define semaphore_owner(sem) \
-	((struct task_struct *)((2*PAGE_MASK) & (sem)->owner))
-
-#define MUTEX ((struct semaphore) { ATOMIC_INIT(1), 0, 0, ATOMIC_INIT(0), NULL })
-#define MUTEX_LOCKED ((struct semaphore) { ATOMIC_INIT(0), 0, 1, ATOMIC_INIT(0), NULL })
+#define MUTEX ((struct semaphore) { ATOMIC_INIT(1), ATOMIC_INIT(0), NULL })
+#define MUTEX_LOCKED ((struct semaphore) { ATOMIC_INIT(0), ATOMIC_INIT(0), NULL })
 
 asmlinkage void __down_failed(void /* special register calling convention */);
 asmlinkage int  __down_failed_interruptible(void  /* params in registers */);
+asmlinkage int  __down_failed_trylock(void  /* params in registers */);
 asmlinkage void __up_wakeup(void /* special register calling convention */);
 
-extern void __down(struct semaphore * sem);
-extern int  __down_interruptible(struct semaphore * sem);
-extern void __up(struct semaphore * sem);
+asmlinkage void __down(struct semaphore * sem);
+asmlinkage int  __down_interruptible(struct semaphore * sem);
+asmlinkage int  __down_trylock(struct semaphore * sem);
+asmlinkage void __up(struct semaphore * sem);
 
 #define sema_init(sem, val)	atomic_set(&((sem)->count), val)
 
-static inline void wake_one_more(struct semaphore * sem)
-{
-	atomic_inc(&sem->waking);
-}
-
-static inline int waking_non_zero(struct semaphore *sem, struct task_struct *tsk)
-{
-#ifndef CONFIG_RMW_INSNS
-	unsigned long flags;
-	int ret = 0;
-
-	save_flags(flags);
-	cli();
-	if (atomic_read(&sem->waking) > 0 || (owner_depth && semaphore_owner(sem) == tsk)) {
-		sem->owner = (unsigned long)tsk;
-		sem->owner_depth++;
-		atomic_dec(&sem->waking);
-		ret = 1;
-	}
-	restore_flags(flags);
-#else
-	int ret, tmp;
-
-	__asm__ __volatile__
-	  ("1:	movel	%2,%0\n"
-	   "    jeq	3f\n"
-	   "2:	movel	%0,%1\n"
-	   "	subql	#1,%1\n"
-	   "	casl	%0,%1,%2\n"
-	   "	jeq	3f\n"
-	   "	tstl	%0\n"
-	   "	jne	2b\n"
-	   "3:"
-	   : "=d" (ret), "=d" (tmp), "=m" (sem->waking));
-
-	ret |= ((sem->owner_depth != 0) && (semaphore_owner(sem) == tsk));
-	if (ret) {
-		sem->owner = (unsigned long)tsk;
-		sem->owner_depth++;
-	}
-
-#endif
-	return ret;
-}
-
 /*
  * This is ugly, but we want the default case to fall through.
  * "down_failed" is a special asm handler that calls the C
@@ -102,8 +49,6 @@
 		"| atomic down operation\n\t"
 		"subql #1,%0@\n\t"
 		"jmi 2f\n\t"
-		"movel %%sp,4(%0)\n"
-		"movel #1,8(%0)\n\t"
 		"1:\n"
 		".section .text.lock,\"ax\"\n"
 		".even\n"
@@ -124,9 +69,6 @@
 		"| atomic interruptible down operation\n\t"
 		"subql #1,%1@\n\t"
 		"jmi 2f\n\t"
-		"movel %%sp,4(%1)\n"
-		"moveql #1,%0\n"
-		"movel %0,8(%1)\n"
 		"clrl %0\n"
 		"1:\n"
 		".section .text.lock,\"ax\"\n"
@@ -140,6 +82,28 @@
 	return result;
 }
 
+extern inline int down_trylock(struct semaphore * sem)
+{
+	register struct semaphore *sem1 __asm__ ("%a1") = sem;
+	register int result __asm__ ("%d0");
+
+	__asm__ __volatile__(
+		"| atomic down trylock operation\n\t"
+		"subql #1,%1@\n\t"
+		"jmi 2f\n\t"
+		"clrl %0\n"
+		"1:\n"
+		".section .text.lock,\"ax\"\n"
+		".even\n"
+		"2:\tpea 1b\n\t"
+		"jbra __down_failed_trylock\n"
+		".previous"
+		: "=d" (result)
+		: "a" (sem1)
+		: "%d0", "memory");
+	return result;
+}
+
 /*
  * Note! This is subtle. We jump to wake people up only if
  * the semaphore was negative (== somebody was waiting on it).
@@ -151,13 +115,13 @@
 	register struct semaphore *sem1 __asm__ ("%a1") = sem;
 	__asm__ __volatile__(
 		"| atomic up operation\n\t"
-		"subql #1,8(%0)\n\t"
 		"addql #1,%0@\n\t"
 		"jle 2f\n"
 		"1:\n"
 		".section .text.lock,\"ax\"\n"
 		".even\n"
-		"2:\tpea 1b\n\t"
+		"2:\t"
+		"pea 1b\n\t"
 		"jbra __up_wakeup\n"
 		".previous"
 		: /* no outputs */