+++ /dev/null
-/*
- * Spin and read/write 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
- *
- * 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.
- */
-
-#include <linux/config.h>
-#include <linux/kernel.h>
-#include <linux/spinlock.h>
-#include <linux/module.h>
-#include <linux/stringify.h>
-#include <asm/hvcall.h>
-#include <asm/iSeries/HvCall.h>
-
-/* waiting for a spinlock... */
-#if defined(CONFIG_PPC_SPLPAR) || defined(CONFIG_PPC_ISERIES)
-
-void __spin_yield(raw_spinlock_t *lock)
-{
- unsigned int lock_value, holder_cpu, yield_count;
- struct paca_struct *holder_paca;
-
- lock_value = lock->slock;
- if (lock_value == 0)
- return;
- holder_cpu = lock_value & 0xffff;
- BUG_ON(holder_cpu >= NR_CPUS);
- holder_paca = &paca[holder_cpu];
- yield_count = holder_paca->lppaca.yield_count;
- if ((yield_count & 1) == 0)
- return; /* virtual cpu is currently running */
- rmb();
- if (lock->slock != lock_value)
- return; /* something has changed */
-#ifdef CONFIG_PPC_ISERIES
- HvCall2(HvCallBaseYieldProcessor, HvCall_YieldToProc,
- ((u64)holder_cpu << 32) | yield_count);
-#else
- plpar_hcall_norets(H_CONFER, get_hard_smp_processor_id(holder_cpu),
- yield_count);
-#endif
-}
-
-/*
- * Waiting for a read lock or a write lock on a rwlock...
- * This turns out to be the same for read and write locks, since
- * we only know the holder if it is write-locked.
- */
-void __rw_yield(raw_rwlock_t *rw)
-{
- int lock_value;
- unsigned int holder_cpu, yield_count;
- struct paca_struct *holder_paca;
-
- lock_value = rw->lock;
- if (lock_value >= 0)
- return; /* no write lock at present */
- holder_cpu = lock_value & 0xffff;
- BUG_ON(holder_cpu >= NR_CPUS);
- holder_paca = &paca[holder_cpu];
- yield_count = holder_paca->lppaca.yield_count;
- if ((yield_count & 1) == 0)
- return; /* virtual cpu is currently running */
- rmb();
- if (rw->lock != lock_value)
- return; /* something has changed */
-#ifdef CONFIG_PPC_ISERIES
- HvCall2(HvCallBaseYieldProcessor, HvCall_YieldToProc,
- ((u64)holder_cpu << 32) | yield_count);
-#else
- plpar_hcall_norets(H_CONFER, get_hard_smp_processor_id(holder_cpu),
- yield_count);
-#endif
-}
-#endif
-
-void __raw_spin_unlock_wait(raw_spinlock_t *lock)
-{
- while (lock->slock) {
- HMT_low();
- if (SHARED_PROCESSOR)
- __spin_yield(lock);
- }
- HMT_medium();
-}
-
-EXPORT_SYMBOL(__raw_spin_unlock_wait);