#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 <asm/atomic.h> #include <asm/bitops.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; } #endif /* _ASM_IA64_SPINLOCK_H */