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Diffstat (limited to 'include/asm-powerpc/spinlock.h')
-rw-r--r-- | include/asm-powerpc/spinlock.h | 295 |
1 files changed, 0 insertions, 295 deletions
diff --git a/include/asm-powerpc/spinlock.h b/include/asm-powerpc/spinlock.h deleted file mode 100644 index f56a843f470..00000000000 --- a/include/asm-powerpc/spinlock.h +++ /dev/null @@ -1,295 +0,0 @@ -#ifndef __ASM_SPINLOCK_H -#define __ASM_SPINLOCK_H -#ifdef __KERNEL__ - -/* - * Simple spin lock operations. - * - * Copyright (C) 2001-2004 Paul Mackerras <paulus@au.ibm.com>, IBM - * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM - * Copyright (C) 2002 Dave Engebretsen <engebret@us.ibm.com>, IBM - * Rework to support virtual processors - * - * Type of int is used as a full 64b word is not necessary. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * (the type definitions are in asm/spinlock_types.h) - */ -#include <linux/irqflags.h> -#ifdef CONFIG_PPC64 -#include <asm/paca.h> -#include <asm/hvcall.h> -#include <asm/iseries/hv_call.h> -#endif -#include <asm/asm-compat.h> -#include <asm/synch.h> - -#define __raw_spin_is_locked(x) ((x)->slock != 0) - -#ifdef CONFIG_PPC64 -/* use 0x800000yy when locked, where yy == CPU number */ -#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token)) -#else -#define LOCK_TOKEN 1 -#endif - -#if defined(CONFIG_PPC64) && defined(CONFIG_SMP) -#define CLEAR_IO_SYNC (get_paca()->io_sync = 0) -#define SYNC_IO do { \ - if (unlikely(get_paca()->io_sync)) { \ - mb(); \ - get_paca()->io_sync = 0; \ - } \ - } while (0) -#else -#define CLEAR_IO_SYNC -#define SYNC_IO -#endif - -/* - * This returns the old value in the lock, so we succeeded - * in getting the lock if the return value is 0. - */ -static inline unsigned long __spin_trylock(raw_spinlock_t *lock) -{ - unsigned long tmp, token; - - token = LOCK_TOKEN; - __asm__ __volatile__( -"1: lwarx %0,0,%2\n\ - cmpwi 0,%0,0\n\ - bne- 2f\n\ - stwcx. %1,0,%2\n\ - bne- 1b\n\ - isync\n\ -2:" : "=&r" (tmp) - : "r" (token), "r" (&lock->slock) - : "cr0", "memory"); - - return tmp; -} - -static inline int __raw_spin_trylock(raw_spinlock_t *lock) -{ - CLEAR_IO_SYNC; - return __spin_trylock(lock) == 0; -} - -/* - * On a system with shared processors (that is, where a physical - * processor is multiplexed between several virtual processors), - * there is no point spinning on a lock if the holder of the lock - * isn't currently scheduled on a physical processor. Instead - * we detect this situation and ask the hypervisor to give the - * rest of our timeslice to the lock holder. - * - * So that we can tell which virtual processor is holding a lock, - * we put 0x80000000 | smp_processor_id() in the lock when it is - * held. Conveniently, we have a word in the paca that holds this - * value. - */ - -#if defined(CONFIG_PPC_SPLPAR) || defined(CONFIG_PPC_ISERIES) -/* We only yield to the hypervisor if we are in shared processor mode */ -#define SHARED_PROCESSOR (get_lppaca()->shared_proc) -extern void __spin_yield(raw_spinlock_t *lock); -extern void __rw_yield(raw_rwlock_t *lock); -#else /* SPLPAR || ISERIES */ -#define __spin_yield(x) barrier() -#define __rw_yield(x) barrier() -#define SHARED_PROCESSOR 0 -#endif - -static inline void __raw_spin_lock(raw_spinlock_t *lock) -{ - CLEAR_IO_SYNC; - while (1) { - if (likely(__spin_trylock(lock) == 0)) - break; - do { - HMT_low(); - if (SHARED_PROCESSOR) - __spin_yield(lock); - } while (unlikely(lock->slock != 0)); - HMT_medium(); - } -} - -static inline -void __raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long flags) -{ - unsigned long flags_dis; - - CLEAR_IO_SYNC; - while (1) { - if (likely(__spin_trylock(lock) == 0)) - break; - local_save_flags(flags_dis); - local_irq_restore(flags); - do { - HMT_low(); - if (SHARED_PROCESSOR) - __spin_yield(lock); - } while (unlikely(lock->slock != 0)); - HMT_medium(); - local_irq_restore(flags_dis); - } -} - -static inline void __raw_spin_unlock(raw_spinlock_t *lock) -{ - SYNC_IO; - __asm__ __volatile__("# __raw_spin_unlock\n\t" - LWSYNC_ON_SMP: : :"memory"); - lock->slock = 0; -} - -#ifdef CONFIG_PPC64 -extern void __raw_spin_unlock_wait(raw_spinlock_t *lock); -#else -#define __raw_spin_unlock_wait(lock) \ - do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0) -#endif - -/* - * 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. - */ - -#define __raw_read_can_lock(rw) ((rw)->lock >= 0) -#define __raw_write_can_lock(rw) (!(rw)->lock) - -#ifdef CONFIG_PPC64 -#define __DO_SIGN_EXTEND "extsw %0,%0\n" -#define WRLOCK_TOKEN LOCK_TOKEN /* it's negative */ -#else -#define __DO_SIGN_EXTEND -#define WRLOCK_TOKEN (-1) -#endif - -/* - * This returns the old value in the lock + 1, - * so we got a read lock if the return value is > 0. - */ -static inline long __read_trylock(raw_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( -"1: lwarx %0,0,%1\n" - __DO_SIGN_EXTEND -" addic. %0,%0,1\n\ - ble- 2f\n" - PPC405_ERR77(0,%1) -" stwcx. %0,0,%1\n\ - bne- 1b\n\ - isync\n\ -2:" : "=&r" (tmp) - : "r" (&rw->lock) - : "cr0", "xer", "memory"); - - return tmp; -} - -/* - * This returns the old value in the lock, - * so we got the write lock if the return value is 0. - */ -static inline long __write_trylock(raw_rwlock_t *rw) -{ - long tmp, token; - - token = WRLOCK_TOKEN; - __asm__ __volatile__( -"1: lwarx %0,0,%2\n\ - cmpwi 0,%0,0\n\ - bne- 2f\n" - PPC405_ERR77(0,%1) -" stwcx. %1,0,%2\n\ - bne- 1b\n\ - isync\n\ -2:" : "=&r" (tmp) - : "r" (token), "r" (&rw->lock) - : "cr0", "memory"); - - return tmp; -} - -static inline void __raw_read_lock(raw_rwlock_t *rw) -{ - while (1) { - if (likely(__read_trylock(rw) > 0)) - break; - do { - HMT_low(); - if (SHARED_PROCESSOR) - __rw_yield(rw); - } while (unlikely(rw->lock < 0)); - HMT_medium(); - } -} - -static inline void __raw_write_lock(raw_rwlock_t *rw) -{ - while (1) { - if (likely(__write_trylock(rw) == 0)) - break; - do { - HMT_low(); - if (SHARED_PROCESSOR) - __rw_yield(rw); - } while (unlikely(rw->lock != 0)); - HMT_medium(); - } -} - -static inline int __raw_read_trylock(raw_rwlock_t *rw) -{ - return __read_trylock(rw) > 0; -} - -static inline int __raw_write_trylock(raw_rwlock_t *rw) -{ - return __write_trylock(rw) == 0; -} - -static inline void __raw_read_unlock(raw_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( - "# read_unlock\n\t" - LWSYNC_ON_SMP -"1: lwarx %0,0,%1\n\ - addic %0,%0,-1\n" - PPC405_ERR77(0,%1) -" stwcx. %0,0,%1\n\ - bne- 1b" - : "=&r"(tmp) - : "r"(&rw->lock) - : "cr0", "memory"); -} - -static inline void __raw_write_unlock(raw_rwlock_t *rw) -{ - __asm__ __volatile__("# write_unlock\n\t" - LWSYNC_ON_SMP: : :"memory"); - rw->lock = 0; -} - -#define _raw_spin_relax(lock) __spin_yield(lock) -#define _raw_read_relax(lock) __rw_yield(lock) -#define _raw_write_relax(lock) __rw_yield(lock) - -#endif /* __KERNEL__ */ -#endif /* __ASM_SPINLOCK_H */ |