1 files changed, 0 insertions, 344 deletions
diff --git a/lib/rwsem-spinlock.c b/lib/rwsem-spinlock.c
deleted file mode 100644
index 40ffde940a8..00000000000
--- a/lib/rwsem-spinlock.c
+++ /dev/null
@@ -1,344 +0,0 @@
-/* rwsem-spinlock.c: R/W semaphores: contention handling functions for
- * generic spinlock implementation
- *
- * Copyright (c) 2001   David Howells (dhowells@redhat.com).
- * - Derived partially from idea by Andrea Arcangeli <andrea@suse.de>
- * - Derived also from comments by Linus
- */
-#include <linux/rwsem.h>
-#include <linux/sched.h>
-#include <linux/module.h>
-
-struct rwsem_waiter {
-	struct list_head list;
-	struct task_struct *task;
-	unsigned int flags;
-#define RWSEM_WAITING_FOR_READ	0x00000001
-#define RWSEM_WAITING_FOR_WRITE	0x00000002
-};
-
-#if RWSEM_DEBUG
-void rwsemtrace(struct rw_semaphore *sem, const char *str)
-{
-	if (sem->debug)
-		printk("[%d] %s({%d,%d})\n",
-		       current->pid, str, sem->activity,
-		       list_empty(&sem->wait_list) ? 0 : 1);
-}
-#endif
-
-/*
- * initialise the semaphore
- */
-void fastcall init_rwsem(struct rw_semaphore *sem)
-{
-	sem->activity = 0;
-	spin_lock_init(&sem->wait_lock);
-	INIT_LIST_HEAD(&sem->wait_list);
-#if RWSEM_DEBUG
-	sem->debug = 0;
-#endif
-}
-
-/*
- * handle the lock release when processes blocked on it that can now run
- * - if we come here, then:
- *   - the 'active count' _reached_ zero
- *   - the 'waiting count' is non-zero
- * - the spinlock must be held by the caller
- * - woken process blocks are discarded from the list after having task zeroed
- * - writers are only woken if wakewrite is non-zero
- */
-static inline struct rw_semaphore *
-__rwsem_do_wake(struct rw_semaphore *sem, int wakewrite)
-{
-	struct rwsem_waiter *waiter;
-	struct task_struct *tsk;
-	int woken;
-
-	rwsemtrace(sem, "Entering __rwsem_do_wake");
-
-	waiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
-
-	if (!wakewrite) {
-		if (waiter->flags & RWSEM_WAITING_FOR_WRITE)
-			goto out;
-		goto dont_wake_writers;
-	}
-
-	/* if we are allowed to wake writers try to grant a single write lock
-	 * if there's a writer at the front of the queue
-	 * - we leave the 'waiting count' incremented to signify potential
-	 *   contention
-	 */
-	if (waiter->flags & RWSEM_WAITING_FOR_WRITE) {
-		sem->activity = -1;
-		list_del(&waiter->list);
-		tsk = waiter->task;
-		/* Don't touch waiter after ->task has been NULLed */
-		smp_mb();
-		waiter->task = NULL;
-		wake_up_process(tsk);
-		put_task_struct(tsk);
-		goto out;
-	}
-
-	/* grant an infinite number of read locks to the front of the queue */
- dont_wake_writers:
-	woken = 0;
-	while (waiter->flags & RWSEM_WAITING_FOR_READ) {
-		struct list_head *next = waiter->list.next;
-
-		list_del(&waiter->list);
-		tsk = waiter->task;
-		smp_mb();
-		waiter->task = NULL;
-		wake_up_process(tsk);
-		put_task_struct(tsk);
-		woken++;
-		if (list_empty(&sem->wait_list))
-			break;
-		waiter = list_entry(next, struct rwsem_waiter, list);
-	}
-
-	sem->activity += woken;
-
- out:
-	rwsemtrace(sem, "Leaving __rwsem_do_wake");
-	return sem;
-}
-
-/*
- * wake a single writer
- */
-static inline struct rw_semaphore *
-__rwsem_wake_one_writer(struct rw_semaphore *sem)
-{
-	struct rwsem_waiter *waiter;
-	struct task_struct *tsk;
-
-	sem->activity = -1;
-
-	waiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
-	list_del(&waiter->list);
-
-	tsk = waiter->task;
-	smp_mb();
-	waiter->task = NULL;
-	wake_up_process(tsk);
-	put_task_struct(tsk);
-	return sem;
-}
-
-/*
- * get a read lock on the semaphore
- */
-void fastcall __sched __down_read(struct rw_semaphore *sem)
-{
-	struct rwsem_waiter waiter;
-	struct task_struct *tsk;
-
-	rwsemtrace(sem, "Entering __down_read");
-
-	spin_lock_irq(&sem->wait_lock);
-
-	if (sem->activity >= 0 && list_empty(&sem->wait_list)) {
-		/* granted */
-		sem->activity++;
-		spin_unlock_irq(&sem->wait_lock);
-		goto out;
-	}
-
-	tsk = current;
-	set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-
-	/* set up my own style of waitqueue */
-	waiter.task = tsk;
-	waiter.flags = RWSEM_WAITING_FOR_READ;
-	get_task_struct(tsk);
-
-	list_add_tail(&waiter.list, &sem->wait_list);
-
-	/* we don't need to touch the semaphore struct anymore */
-	spin_unlock_irq(&sem->wait_lock);
-
-	/* wait to be given the lock */
-	for (;;) {
-		if (!waiter.task)
-			break;
-		schedule();
-		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-	}
-
-	tsk->state = TASK_RUNNING;
-
- out:
-	rwsemtrace(sem, "Leaving __down_read");
-}
-
-/*
- * trylock for reading -- returns 1 if successful, 0 if contention
- */
-int fastcall __down_read_trylock(struct rw_semaphore *sem)
-{
-	unsigned long flags;
-	int ret = 0;
-
-	rwsemtrace(sem, "Entering __down_read_trylock");
-
-	spin_lock_irqsave(&sem->wait_lock, flags);
-
-	if (sem->activity >= 0 && list_empty(&sem->wait_list)) {
-		/* granted */
-		sem->activity++;
-		ret = 1;
-	}
-
-	spin_unlock_irqrestore(&sem->wait_lock, flags);
-
-	rwsemtrace(sem, "Leaving __down_read_trylock");
-	return ret;
-}
-
-/*
- * get a write lock on the semaphore
- * - we increment the waiting count anyway to indicate an exclusive lock
- */
-void fastcall __sched __down_write(struct rw_semaphore *sem)
-{
-	struct rwsem_waiter waiter;
-	struct task_struct *tsk;
-
-	rwsemtrace(sem, "Entering __down_write");
-
-	spin_lock_irq(&sem->wait_lock);
-
-	if (sem->activity == 0 && list_empty(&sem->wait_list)) {
-		/* granted */
-		sem->activity = -1;
-		spin_unlock_irq(&sem->wait_lock);
-		goto out;
-	}
-
-	tsk = current;
-	set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-
-	/* set up my own style of waitqueue */
-	waiter.task = tsk;
-	waiter.flags = RWSEM_WAITING_FOR_WRITE;
-	get_task_struct(tsk);
-
-	list_add_tail(&waiter.list, &sem->wait_list);
-
-	/* we don't need to touch the semaphore struct anymore */
-	spin_unlock_irq(&sem->wait_lock);
-
-	/* wait to be given the lock */
-	for (;;) {
-		if (!waiter.task)
-			break;
-		schedule();
-		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-	}
-
-	tsk->state = TASK_RUNNING;
-
- out:
-	rwsemtrace(sem, "Leaving __down_write");
-}
-
-/*
- * trylock for writing -- returns 1 if successful, 0 if contention
- */
-int fastcall __down_write_trylock(struct rw_semaphore *sem)
-{
-	unsigned long flags;
-	int ret = 0;
-
-	rwsemtrace(sem, "Entering __down_write_trylock");
-
-	spin_lock_irqsave(&sem->wait_lock, flags);
-
-	if (sem->activity == 0 && list_empty(&sem->wait_list)) {
-		/* granted */
-		sem->activity = -1;
-		ret = 1;
-	}
-
-	spin_unlock_irqrestore(&sem->wait_lock, flags);
-
-	rwsemtrace(sem, "Leaving __down_write_trylock");
-	return ret;
-}
-
-/*
- * release a read lock on the semaphore
- */
-void fastcall __up_read(struct rw_semaphore *sem)
-{
-	unsigned long flags;
-
-	rwsemtrace(sem, "Entering __up_read");
-
-	spin_lock_irqsave(&sem->wait_lock, flags);
-
-	if (--sem->activity == 0 && !list_empty(&sem->wait_list))
-		sem = __rwsem_wake_one_writer(sem);
-
-	spin_unlock_irqrestore(&sem->wait_lock, flags);
-
-	rwsemtrace(sem, "Leaving __up_read");
-}
-
-/*
- * release a write lock on the semaphore
- */
-void fastcall __up_write(struct rw_semaphore *sem)
-{
-	unsigned long flags;
-
-	rwsemtrace(sem, "Entering __up_write");
-
-	spin_lock_irqsave(&sem->wait_lock, flags);
-
-	sem->activity = 0;
-	if (!list_empty(&sem->wait_list))
-		sem = __rwsem_do_wake(sem, 1);
-
-	spin_unlock_irqrestore(&sem->wait_lock, flags);
-
-	rwsemtrace(sem, "Leaving __up_write");
-}
-
-/*
- * downgrade a write lock into a read lock
- * - just wake up any readers at the front of the queue
- */
-void fastcall __downgrade_write(struct rw_semaphore *sem)
-{
-	unsigned long flags;
-
-	rwsemtrace(sem, "Entering __downgrade_write");
-
-	spin_lock_irqsave(&sem->wait_lock, flags);
-
-	sem->activity = 1;
-	if (!list_empty(&sem->wait_list))
-		sem = __rwsem_do_wake(sem, 0);
-
-	spin_unlock_irqrestore(&sem->wait_lock, flags);
-
-	rwsemtrace(sem, "Leaving __downgrade_write");
-}
-
-EXPORT_SYMBOL(init_rwsem);
-EXPORT_SYMBOL(__down_read);
-EXPORT_SYMBOL(__down_read_trylock);
-EXPORT_SYMBOL(__down_write);
-EXPORT_SYMBOL(__down_write_trylock);
-EXPORT_SYMBOL(__up_read);
-EXPORT_SYMBOL(__up_write);
-EXPORT_SYMBOL(__downgrade_write);
-#if RWSEM_DEBUG
-EXPORT_SYMBOL(rwsemtrace);
-#endif