(2006-08-06) rescue-bootcd

extra/linux-2.6.10/kernel/spinlock.c

@@ -0,0 +1,308 @@
+/*
+ * Copyright (2004) Linus Torvalds
+ *
+ * Author: Zwane Mwaikambo <zwane@fsmlabs.com>
+ */
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <linux/preempt.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+
+int __lockfunc _spin_trylock(spinlock_t *lock)
+{
+	preempt_disable();
+	if (_raw_spin_trylock(lock))
+		return 1;
+	
+	preempt_enable();
+	return 0;
+}
+EXPORT_SYMBOL(_spin_trylock);
+
+int __lockfunc _write_trylock(rwlock_t *lock)
+{
+	preempt_disable();
+	if (_raw_write_trylock(lock))
+		return 1;
+
+	preempt_enable();
+	return 0;
+}
+EXPORT_SYMBOL(_write_trylock);
+
+#ifdef CONFIG_PREEMPT
+/*
+ * This could be a long-held lock.  If another CPU holds it for a long time,
+ * and that CPU is not asked to reschedule then *this* CPU will spin on the
+ * lock for a long time, even if *this* CPU is asked to reschedule.
+ *
+ * So what we do here, in the slow (contended) path is to spin on the lock by
+ * hand while permitting preemption.
+ *
+ * Called inside preempt_disable().
+ */
+static inline void __preempt_spin_lock(spinlock_t *lock)
+{
+	if (preempt_count() > 1) {
+		_raw_spin_lock(lock);
+		return;
+	}
+
+	do {
+		preempt_enable();
+		while (spin_is_locked(lock))
+			cpu_relax();
+		preempt_disable();
+	} while (!_raw_spin_trylock(lock));
+}
+
+void __lockfunc _spin_lock(spinlock_t *lock)
+{
+	preempt_disable();
+	if (unlikely(!_raw_spin_trylock(lock)))
+		__preempt_spin_lock(lock);
+}
+
+static inline void __preempt_write_lock(rwlock_t *lock)
+{
+	if (preempt_count() > 1) {
+		_raw_write_lock(lock);
+		return;
+	}
+
+	do {
+		preempt_enable();
+		while (rwlock_is_locked(lock))
+			cpu_relax();
+		preempt_disable();
+	} while (!_raw_write_trylock(lock));
+}
+
+void __lockfunc _write_lock(rwlock_t *lock)
+{
+	preempt_disable();
+	if (unlikely(!_raw_write_trylock(lock)))
+		__preempt_write_lock(lock);
+}
+#else
+void __lockfunc _spin_lock(spinlock_t *lock)
+{
+	preempt_disable();
+	_raw_spin_lock(lock);
+}
+
+void __lockfunc _write_lock(rwlock_t *lock)
+{
+	preempt_disable();
+	_raw_write_lock(lock);
+}
+#endif
+EXPORT_SYMBOL(_spin_lock);
+EXPORT_SYMBOL(_write_lock);
+
+void __lockfunc _read_lock(rwlock_t *lock)
+{
+	preempt_disable();
+	_raw_read_lock(lock);
+}
+EXPORT_SYMBOL(_read_lock);
+
+void __lockfunc _spin_unlock(spinlock_t *lock)
+{
+	_raw_spin_unlock(lock);
+	preempt_enable();
+}
+EXPORT_SYMBOL(_spin_unlock);
+
+void __lockfunc _write_unlock(rwlock_t *lock)
+{
+	_raw_write_unlock(lock);
+	preempt_enable();
+}
+EXPORT_SYMBOL(_write_unlock);
+
+void __lockfunc _read_unlock(rwlock_t *lock)
+{
+	_raw_read_unlock(lock);
+	preempt_enable();
+}
+EXPORT_SYMBOL(_read_unlock);
+
+unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	preempt_disable();
+	_raw_spin_lock_flags(lock, flags);
+	return flags;
+}
+EXPORT_SYMBOL(_spin_lock_irqsave);
+
+void __lockfunc _spin_lock_irq(spinlock_t *lock)
+{
+	local_irq_disable();
+	preempt_disable();
+	_raw_spin_lock(lock);
+}
+EXPORT_SYMBOL(_spin_lock_irq);
+
+void __lockfunc _spin_lock_bh(spinlock_t *lock)
+{
+	local_bh_disable();
+	preempt_disable();
+	_raw_spin_lock(lock);
+}
+EXPORT_SYMBOL(_spin_lock_bh);
+
+unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	preempt_disable();
+	_raw_read_lock(lock);
+	return flags;
+}
+EXPORT_SYMBOL(_read_lock_irqsave);
+
+void __lockfunc _read_lock_irq(rwlock_t *lock)
+{
+	local_irq_disable();
+	preempt_disable();
+	_raw_read_lock(lock);
+}
+EXPORT_SYMBOL(_read_lock_irq);
+
+void __lockfunc _read_lock_bh(rwlock_t *lock)
+{
+	local_bh_disable();
+	preempt_disable();
+	_raw_read_lock(lock);
+}
+EXPORT_SYMBOL(_read_lock_bh);
+
+unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	preempt_disable();
+	_raw_write_lock(lock);
+	return flags;
+}
+EXPORT_SYMBOL(_write_lock_irqsave);
+
+void __lockfunc _write_lock_irq(rwlock_t *lock)
+{
+	local_irq_disable();
+	preempt_disable();
+	_raw_write_lock(lock);
+}
+EXPORT_SYMBOL(_write_lock_irq);
+
+void __lockfunc _write_lock_bh(rwlock_t *lock)
+{
+	local_bh_disable();
+	preempt_disable();
+	_raw_write_lock(lock);
+}
+EXPORT_SYMBOL(_write_lock_bh);
+
+void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
+{
+	_raw_spin_unlock(lock);
+	local_irq_restore(flags);
+	preempt_enable();
+}
+EXPORT_SYMBOL(_spin_unlock_irqrestore);
+
+void __lockfunc _spin_unlock_irq(spinlock_t *lock)
+{
+	_raw_spin_unlock(lock);
+	local_irq_enable();
+	preempt_enable();
+}
+EXPORT_SYMBOL(_spin_unlock_irq);
+
+void __lockfunc _spin_unlock_bh(spinlock_t *lock)
+{
+	_raw_spin_unlock(lock);
+	preempt_enable();
+	local_bh_enable();
+}
+EXPORT_SYMBOL(_spin_unlock_bh);
+
+void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+{
+	_raw_read_unlock(lock);
+	local_irq_restore(flags);
+	preempt_enable();
+}
+EXPORT_SYMBOL(_read_unlock_irqrestore);
+
+void __lockfunc _read_unlock_irq(rwlock_t *lock)
+{
+	_raw_read_unlock(lock);
+	local_irq_enable();
+	preempt_enable();
+}
+EXPORT_SYMBOL(_read_unlock_irq);
+
+void __lockfunc _read_unlock_bh(rwlock_t *lock)
+{
+	_raw_read_unlock(lock);
+	preempt_enable();
+	local_bh_enable();
+}
+EXPORT_SYMBOL(_read_unlock_bh);
+
+void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+{
+	_raw_write_unlock(lock);
+	local_irq_restore(flags);
+	preempt_enable();
+}
+EXPORT_SYMBOL(_write_unlock_irqrestore);
+
+void __lockfunc _write_unlock_irq(rwlock_t *lock)
+{
+	_raw_write_unlock(lock);
+	local_irq_enable();
+	preempt_enable();
+}
+EXPORT_SYMBOL(_write_unlock_irq);
+
+void __lockfunc _write_unlock_bh(rwlock_t *lock)
+{
+	_raw_write_unlock(lock);
+	preempt_enable();
+	local_bh_enable();
+}
+EXPORT_SYMBOL(_write_unlock_bh);
+
+int __lockfunc _spin_trylock_bh(spinlock_t *lock)
+{
+	local_bh_disable();
+	preempt_disable();
+	if (_raw_spin_trylock(lock))
+		return 1;
+
+	preempt_enable();
+	local_bh_enable();
+	return 0;
+}
+EXPORT_SYMBOL(_spin_trylock_bh);
+
+int in_lock_functions(unsigned long addr)
+{
+	/* Linker adds these: start and end of __lockfunc functions */
+	extern char __lock_text_start[], __lock_text_end[];
+
+	return addr >= (unsigned long)__lock_text_start
+	&& addr < (unsigned long)__lock_text_end;
+}
+EXPORT_SYMBOL(in_lock_functions);