diff options
Diffstat (limited to 'old/xenolinux-2.4.16-sparse/include/asm-xeno/spinlock.h')
| -rw-r--r-- | old/xenolinux-2.4.16-sparse/include/asm-xeno/spinlock.h | 212 |
1 files changed, 0 insertions, 212 deletions
diff --git a/old/xenolinux-2.4.16-sparse/include/asm-xeno/spinlock.h b/old/xenolinux-2.4.16-sparse/include/asm-xeno/spinlock.h deleted file mode 100644 index dbdd68b41b..0000000000 --- a/old/xenolinux-2.4.16-sparse/include/asm-xeno/spinlock.h +++ /dev/null @@ -1,212 +0,0 @@ -#ifndef __ASM_SPINLOCK_H -#define __ASM_SPINLOCK_H - -#include <asm/atomic.h> -#include <asm/rwlock.h> -#include <asm/page.h> -#include <linux/config.h> - -extern int printk(const char * fmt, ...) - __attribute__ ((format (printf, 1, 2))); - -/* It seems that people are forgetting to - * initialize their spinlocks properly, tsk tsk. - * Remember to turn this off in 2.4. -ben - */ -#if defined(CONFIG_DEBUG_SPINLOCK) -#define SPINLOCK_DEBUG 1 -#else -#define SPINLOCK_DEBUG 0 -#endif - -/* - * Your basic SMP spinlocks, allowing only a single CPU anywhere - */ - -typedef struct { - volatile unsigned int lock; -#if SPINLOCK_DEBUG - unsigned magic; -#endif -} spinlock_t; - -#define SPINLOCK_MAGIC 0xdead4ead - -#if SPINLOCK_DEBUG -#define SPINLOCK_MAGIC_INIT , SPINLOCK_MAGIC -#else -#define SPINLOCK_MAGIC_INIT /* */ -#endif - -#define SPIN_LOCK_UNLOCKED (spinlock_t) { 1 SPINLOCK_MAGIC_INIT } - -#define spin_lock_init(x) do { *(x) = SPIN_LOCK_UNLOCKED; } while(0) - -/* - * Simple spin lock operations. There are two variants, one clears IRQ's - * on the local processor, one does not. - * - * We make no fairness assumptions. They have a cost. - */ - -#define spin_is_locked(x) (*(volatile char *)(&(x)->lock) <= 0) -#define spin_unlock_wait(x) do { barrier(); } while(spin_is_locked(x)) - -#define spin_lock_string \ - "\n1:\t" \ - "lock ; decb %0\n\t" \ - "js 2f\n" \ - ".section .text.lock,\"ax\"\n" \ - "2:\t" \ - "cmpb $0,%0\n\t" \ - "rep;nop\n\t" \ - "jle 2b\n\t" \ - "jmp 1b\n" \ - ".previous" - -/* - * This works. Despite all the confusion. - * (except on PPro SMP or if we are using OOSTORE) - * (PPro errata 66, 92) - */ - -#if !defined(CONFIG_X86_OOSTORE) && !defined(CONFIG_X86_PPRO_FENCE) - -#define spin_unlock_string \ - "movb $1,%0" \ - :"=m" (lock->lock) : : "memory" - - -static inline void spin_unlock(spinlock_t *lock) -{ -#if SPINLOCK_DEBUG - if (lock->magic != SPINLOCK_MAGIC) - BUG(); - if (!spin_is_locked(lock)) - BUG(); -#endif - __asm__ __volatile__( - spin_unlock_string - ); -} - -#else - -#define spin_unlock_string \ - "xchgb %b0, %1" \ - :"=q" (oldval), "=m" (lock->lock) \ - :"0" (oldval) : "memory" - -static inline void spin_unlock(spinlock_t *lock) -{ - char oldval = 1; -#if SPINLOCK_DEBUG - if (lock->magic != SPINLOCK_MAGIC) - BUG(); - if (!spin_is_locked(lock)) - BUG(); -#endif - __asm__ __volatile__( - spin_unlock_string - ); -} - -#endif - -static inline int spin_trylock(spinlock_t *lock) -{ - char oldval; - __asm__ __volatile__( - "xchgb %b0,%1" - :"=q" (oldval), "=m" (lock->lock) - :"0" (0) : "memory"); - return oldval > 0; -} - -static inline void spin_lock(spinlock_t *lock) -{ -#if SPINLOCK_DEBUG - __label__ here; -here: - if (lock->magic != SPINLOCK_MAGIC) { -printk("eip: %p\n", &&here); - BUG(); - } -#endif - __asm__ __volatile__( - spin_lock_string - :"=m" (lock->lock) : : "memory"); -} - - -/* - * Read-write spinlocks, allowing multiple readers - * but only one writer. - * - * NOTE! it is quite common to have readers in interrupts - * but no interrupt writers. For those circumstances we - * can "mix" irq-safe locks - any writer needs to get a - * irq-safe write-lock, but readers can get non-irqsafe - * read-locks. - */ -typedef struct { - volatile unsigned int lock; -#if SPINLOCK_DEBUG - unsigned magic; -#endif -} rwlock_t; - -#define RWLOCK_MAGIC 0xdeaf1eed - -#if SPINLOCK_DEBUG -#define RWLOCK_MAGIC_INIT , RWLOCK_MAGIC -#else -#define RWLOCK_MAGIC_INIT /* */ -#endif - -#define RW_LOCK_UNLOCKED (rwlock_t) { RW_LOCK_BIAS RWLOCK_MAGIC_INIT } - -#define rwlock_init(x) do { *(x) = RW_LOCK_UNLOCKED; } while(0) - -/* - * On x86, we implement read-write locks as a 32-bit counter - * with the high bit (sign) being the "contended" bit. - * - * The inline assembly is non-obvious. Think about it. - * - * Changed to use the same technique as rw semaphores. See - * semaphore.h for details. -ben - */ -/* the spinlock helpers are in arch/i386/kernel/semaphore.c */ - -static inline void read_lock(rwlock_t *rw) -{ -#if SPINLOCK_DEBUG - if (rw->magic != RWLOCK_MAGIC) - BUG(); -#endif - __build_read_lock(rw, "__read_lock_failed"); -} - -static inline void write_lock(rwlock_t *rw) -{ -#if SPINLOCK_DEBUG - if (rw->magic != RWLOCK_MAGIC) - BUG(); -#endif - __build_write_lock(rw, "__write_lock_failed"); -} - -#define read_unlock(rw) asm volatile("lock ; incl %0" :"=m" ((rw)->lock) : : "memory") -#define write_unlock(rw) asm volatile("lock ; addl $" RW_LOCK_BIAS_STR ",%0":"=m" ((rw)->lock) : : "memory") - -static inline int write_trylock(rwlock_t *lock) -{ - atomic_t *count = (atomic_t *)lock; - if (atomic_sub_and_test(RW_LOCK_BIAS, count)) - return 1; - atomic_add(RW_LOCK_BIAS, count); - return 0; -} - -#endif /* __ASM_SPINLOCK_H */ |