| #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__ == 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 */ |