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#ifndef _ASM_IA64_SPINLOCK_H
#define _ASM_IA64_SPINLOCK_H
/*
* Copyright (C) 1998-2003 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
*
* This file is used for SMP configurations only.
*/
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/bitops.h>
#include <asm/atomic.h>
#include <asm/intrinsics.h>
#include <asm/system.h>
#define __raw_spin_lock_init(x) ((x)->lock = 0)
#ifdef ASM_SUPPORTED
/*
* Try to get the lock. If we fail to get the lock, make a non-standard call to
* ia64_spinlock_contention(). We do not use a normal call because that would force all
* callers of __raw_spin_lock() to be non-leaf routines. Instead, ia64_spinlock_contention() is
* carefully coded to touch only those registers that __raw_spin_lock() marks "clobbered".
*/
#define IA64_SPINLOCK_CLOBBERS "ar.ccv", "ar.pfs", "p14", "p15", "r27", "r28", "r29", "r30", "b6", "memory"
static inline void
__raw_spin_lock_flags (raw_spinlock_t *lock, unsigned long flags)
{
register volatile unsigned int *ptr asm ("r31") = &lock->lock;
#if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
# ifdef CONFIG_ITANIUM
/* don't use brl on Itanium... */
asm volatile ("{\n\t"
" mov ar.ccv = r0\n\t"
" mov r28 = ip\n\t"
" mov r30 = 1;;\n\t"
"}\n\t"
"cmpxchg4.acq r30 = [%1], r30, ar.ccv\n\t"
"movl r29 = ia64_spinlock_contention_pre3_4;;\n\t"
"cmp4.ne p14, p0 = r30, r0\n\t"
"mov b6 = r29;;\n\t"
"mov r27=%2\n\t"
"(p14) br.cond.spnt.many b6"
: "=r"(ptr) : "r"(ptr), "r" (flags) : IA64_SPINLOCK_CLOBBERS);
# else
asm volatile ("{\n\t"
" mov ar.ccv = r0\n\t"
" mov r28 = ip\n\t"
" mov r30 = 1;;\n\t"
"}\n\t"
"cmpxchg4.acq r30 = [%1], r30, ar.ccv;;\n\t"
"cmp4.ne p14, p0 = r30, r0\n\t"
"mov r27=%2\n\t"
"(p14) brl.cond.spnt.many ia64_spinlock_contention_pre3_4;;"
: "=r"(ptr) : "r"(ptr), "r" (flags) : IA64_SPINLOCK_CLOBBERS);
# endif /* CONFIG_MCKINLEY */
#else
# ifdef CONFIG_ITANIUM
/* don't use brl on Itanium... */
/* mis-declare, so we get the entry-point, not it's function descriptor: */
asm volatile ("mov r30 = 1\n\t"
"mov r27=%2\n\t"
"mov ar.ccv = r0;;\n\t"
"cmpxchg4.acq r30 = [%0], r30, ar.ccv\n\t"
"movl r29 = ia64_spinlock_contention;;\n\t"
"cmp4.ne p14, p0 = r30, r0\n\t"
"mov b6 = r29;;\n\t"
"(p14) br.call.spnt.many b6 = b6"
: "=r"(ptr) : "r"(ptr), "r" (flags) : IA64_SPINLOCK_CLOBBERS);
# else
asm volatile ("mov r30 = 1\n\t"
"mov r27=%2\n\t"
"mov ar.ccv = r0;;\n\t"
"cmpxchg4.acq r30 = [%0], r30, ar.ccv;;\n\t"
"cmp4.ne p14, p0 = r30, r0\n\t"
"(p14) brl.call.spnt.many b6=ia64_spinlock_contention;;"
: "=r"(ptr) : "r"(ptr), "r" (flags) : IA64_SPINLOCK_CLOBBERS);
# endif /* CONFIG_MCKINLEY */
#endif
}
#define __raw_spin_lock(lock) __raw_spin_lock_flags(lock, 0)
/* Unlock by doing an ordered store and releasing the cacheline with nta */
static inline void __raw_spin_unlock(raw_spinlock_t *x) {
barrier();
asm volatile ("st4.rel.nta [%0] = r0\n\t" :: "r"(x));
}
#else /* !ASM_SUPPORTED */
#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
# define __raw_spin_lock(x) \
do { \
__u32 *ia64_spinlock_ptr = (__u32 *) (x); \
__u64 ia64_spinlock_val; \
ia64_spinlock_val = ia64_cmpxchg4_acq(ia64_spinlock_ptr, 1, 0); \
if (unlikely(ia64_spinlock_val)) { \
do { \
while (*ia64_spinlock_ptr) \
ia64_barrier(); \
ia64_spinlock_val = ia64_cmpxchg4_acq(ia64_spinlock_ptr, 1, 0); \
} while (ia64_spinlock_val); \
} \
} while (0)
#define __raw_spin_unlock(x) do { barrier(); ((raw_spinlock_t *) x)->lock = 0; } while (0)
#endif /* !ASM_SUPPORTED */
#define __raw_spin_is_locked(x) ((x)->lock != 0)
#define __raw_spin_trylock(x) (cmpxchg_acq(&(x)->lock, 0, 1) == 0)
#define __raw_spin_unlock_wait(lock) \
do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0)
#define __raw_read_can_lock(rw) (*(volatile int *)(rw) >= 0)
#define __raw_write_can_lock(rw) (*(volatile int *)(rw) == 0)
#define __raw_read_lock(rw) \
do { \
raw_rwlock_t *__read_lock_ptr = (rw); \
\
while (unlikely(ia64_fetchadd(1, (int *) __read_lock_ptr, acq) < 0)) { \
ia64_fetchadd(-1, (int *) __read_lock_ptr, rel); \
while (*(volatile int *)__read_lock_ptr < 0) \
cpu_relax(); \
} \
} while (0)
#define __raw_read_unlock(rw) \
do { \
raw_rwlock_t *__read_lock_ptr = (rw); \
ia64_fetchadd(-1, (int *) __read_lock_ptr, rel); \
} while (0)
#ifdef ASM_SUPPORTED
#define __raw_write_lock(rw) \
do { \
__asm__ __volatile__ ( \
"mov ar.ccv = r0\n" \
"dep r29 = -1, r0, 31, 1;;\n" \
"1:\n" \
"ld4 r2 = [%0];;\n" \
"cmp4.eq p0,p7 = r0,r2\n" \
"(p7) br.cond.spnt.few 1b \n" \
"cmpxchg4.acq r2 = [%0], r29, ar.ccv;;\n" \
"cmp4.eq p0,p7 = r0, r2\n" \
"(p7) br.cond.spnt.few 1b;;\n" \
:: "r"(rw) : "ar.ccv", "p7", "r2", "r29", "memory"); \
} while(0)
#define __raw_write_trylock(rw) \
({ \
register long result; \
\
__asm__ __volatile__ ( \
"mov ar.ccv = r0\n" \
"dep r29 = -1, r0, 31, 1;;\n" \
"cmpxchg4.acq %0 = [%1], r29, ar.ccv\n" \
: "=r"(result) : "r"(rw) : "ar.ccv", "r29", "memory"); \
(result == 0); \
})
static inline void __raw_write_unlock(raw_rwlock_t *x)
{
u8 *y = (u8 *)x;
barrier();
asm volatile ("st1.rel.nta [%0] = r0\n\t" :: "r"(y+3) : "memory" );
}
#else /* !ASM_SUPPORTED */
#define __raw_write_lock(l) \
({ \
__u64 ia64_val, ia64_set_val = ia64_dep_mi(-1, 0, 31, 1); \
__u32 *ia64_write_lock_ptr = (__u32 *) (l); \
do { \
while (*ia64_write_lock_ptr) \
ia64_barrier(); \
ia64_val = ia64_cmpxchg4_acq(ia64_write_lock_ptr, ia64_set_val, 0); \
} while (ia64_val); \
})
#define __raw_write_trylock(rw) \
({ \
__u64 ia64_val; \
__u64 ia64_set_val = ia64_dep_mi(-1, 0, 31,1); \
ia64_val = ia64_cmpxchg4_acq((__u32 *)(rw), ia64_set_val, 0); \
(ia64_val == 0); \
})
static inline void __raw_write_unlock(raw_rwlock_t *x)
{
barrier();
x->write_lock = 0;
}
#endif /* !ASM_SUPPORTED */
static inline int __raw_read_trylock(raw_rwlock_t *x)
{
union {
raw_rwlock_t lock;
__u32 word;
} old, new;
old.lock = new.lock = *x;
old.lock.write_lock = new.lock.write_lock = 0;
++new.lock.read_counter;
return (u32)ia64_cmpxchg4_acq((__u32 *)(x), new.word, old.word) == old.word;
}
#define _raw_spin_relax(lock) cpu_relax()
#define _raw_read_relax(lock) cpu_relax()
#define _raw_write_relax(lock) cpu_relax()
#endif /* _ASM_IA64_SPINLOCK_H */
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