From 0212ddd839470f7a54cccccbaecd4833b4123da2 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Sat, 19 Nov 2005 20:50:46 +1100 Subject: powerpc: Merge spinlock.h The result is mostly similar to the original ppc64 version but with some adaptations for 32-bit compilation. include/asm-ppc64 is now empty! Signed-off-by: Paul Mackerras --- include/asm-ppc64/spinlock.h | 241 ------------------------------------------- 1 file changed, 241 deletions(-) delete mode 100644 include/asm-ppc64/spinlock.h (limited to 'include/asm-ppc64') diff --git a/include/asm-ppc64/spinlock.h b/include/asm-ppc64/spinlock.h deleted file mode 100644 index 7d84fb5e39f..00000000000 --- a/include/asm-ppc64/spinlock.h +++ /dev/null @@ -1,241 +0,0 @@ -#ifndef __ASM_SPINLOCK_H -#define __ASM_SPINLOCK_H - -/* - * Simple spin lock operations. - * - * Copyright (C) 2001-2004 Paul Mackerras , IBM - * Copyright (C) 2001 Anton Blanchard , IBM - * Copyright (C) 2002 Dave Engebretsen , 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 -#include -#include -#include - -#define __raw_spin_is_locked(x) ((x)->slock != 0) - -/* - * 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, tmp2; - - __asm__ __volatile__( -" lwz %1,%3(13) # __spin_trylock\n\ -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" (tmp2) - : "r" (&lock->slock), "i" (offsetof(struct paca_struct, lock_token)) - : "cr0", "memory"); - - return tmp; -} - -static int __inline__ __raw_spin_trylock(raw_spinlock_t *lock) -{ - 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_paca()->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 void __inline__ __raw_spin_lock(raw_spinlock_t *lock) -{ - 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 void __inline__ __raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long flags) -{ - unsigned long flags_dis; - - 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) -{ - __asm__ __volatile__("lwsync # __raw_spin_unlock": : :"memory"); - lock->slock = 0; -} - -extern void __raw_spin_unlock_wait(raw_spinlock_t *lock); - -/* - * 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) - -/* - * This returns the old value in the lock + 1, - * so we got a read lock if the return value is > 0. - */ -static long __inline__ __read_trylock(raw_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( -"1: lwarx %0,0,%1 # read_trylock\n\ - extsw %0,%0\n\ - addic. %0,%0,1\n\ - ble- 2f\n\ - 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, tmp2; - - __asm__ __volatile__( -" lwz %1,%3(13) # write_trylock\n\ -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" (tmp2) - : "r" (&rw->lock), "i" (offsetof(struct paca_struct, lock_token)) - : "cr0", "memory"); - - return tmp; -} - -static void __inline__ __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 void __inline__ __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 int __inline__ __raw_read_trylock(raw_rwlock_t *rw) -{ - return __read_trylock(rw) > 0; -} - -static int __inline__ __raw_write_trylock(raw_rwlock_t *rw) -{ - return __write_trylock(rw) == 0; -} - -static void __inline__ __raw_read_unlock(raw_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( - "eieio # read_unlock\n\ -1: lwarx %0,0,%1\n\ - addic %0,%0,-1\n\ - 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__("lwsync # write_unlock": : :"memory"); - rw->lock = 0; -} - -#endif /* __ASM_SPINLOCK_H */ -- cgit v1.2.3