diff options
Diffstat (limited to 'arch/frv/kernel/semaphore.c')
-rw-r--r-- | arch/frv/kernel/semaphore.c | 155 |
1 files changed, 0 insertions, 155 deletions
diff --git a/arch/frv/kernel/semaphore.c b/arch/frv/kernel/semaphore.c deleted file mode 100644 index 7ee3a147b47..00000000000 --- a/arch/frv/kernel/semaphore.c +++ /dev/null @@ -1,155 +0,0 @@ -/* semaphore.c: FR-V semaphores - * - * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - Derived from lib/rwsem-spinlock.c - * - * 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/sched.h> -#include <linux/module.h> -#include <asm/semaphore.h> - -struct sem_waiter { - struct list_head list; - struct task_struct *task; -}; - -#ifdef CONFIG_DEBUG_SEMAPHORE -void semtrace(struct semaphore *sem, const char *str) -{ - if (sem->debug) - printk("[%d] %s({%d,%d})\n", - current->pid, - str, - sem->counter, - list_empty(&sem->wait_list) ? 0 : 1); -} -#else -#define semtrace(SEM,STR) do { } while(0) -#endif - -/* - * wait for a token to be granted from a semaphore - * - entered with lock held and interrupts disabled - */ -void __down(struct semaphore *sem, unsigned long flags) -{ - struct task_struct *tsk = current; - struct sem_waiter waiter; - - semtrace(sem, "Entering __down"); - - /* set up my own style of waitqueue */ - waiter.task = tsk; - get_task_struct(tsk); - - list_add_tail(&waiter.list, &sem->wait_list); - - /* we don't need to touch the semaphore struct anymore */ - spin_unlock_irqrestore(&sem->wait_lock, flags); - - /* wait to be given the semaphore */ - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - - for (;;) { - if (list_empty(&waiter.list)) - break; - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - - tsk->state = TASK_RUNNING; - semtrace(sem, "Leaving __down"); -} - -EXPORT_SYMBOL(__down); - -/* - * interruptibly wait for a token to be granted from a semaphore - * - entered with lock held and interrupts disabled - */ -int __down_interruptible(struct semaphore *sem, unsigned long flags) -{ - struct task_struct *tsk = current; - struct sem_waiter waiter; - int ret; - - semtrace(sem,"Entering __down_interruptible"); - - /* set up my own style of waitqueue */ - waiter.task = tsk; - get_task_struct(tsk); - - list_add_tail(&waiter.list, &sem->wait_list); - - /* we don't need to touch the semaphore struct anymore */ - set_task_state(tsk, TASK_INTERRUPTIBLE); - - spin_unlock_irqrestore(&sem->wait_lock, flags); - - /* wait to be given the semaphore */ - ret = 0; - for (;;) { - if (list_empty(&waiter.list)) - break; - if (unlikely(signal_pending(current))) - goto interrupted; - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - - out: - tsk->state = TASK_RUNNING; - semtrace(sem, "Leaving __down_interruptible"); - return ret; - - interrupted: - spin_lock_irqsave(&sem->wait_lock, flags); - - if (!list_empty(&waiter.list)) { - list_del(&waiter.list); - ret = -EINTR; - } - - spin_unlock_irqrestore(&sem->wait_lock, flags); - if (ret == -EINTR) - put_task_struct(current); - goto out; -} - -EXPORT_SYMBOL(__down_interruptible); - -/* - * release a single token back to a semaphore - * - entered with lock held and interrupts disabled - */ -void __up(struct semaphore *sem) -{ - struct task_struct *tsk; - struct sem_waiter *waiter; - - semtrace(sem,"Entering __up"); - - /* grant the token to the process at the front of the queue */ - waiter = list_entry(sem->wait_list.next, struct sem_waiter, list); - - /* We must be careful not to touch 'waiter' after we set ->task = NULL. - * It is allocated on the waiter's stack and may become invalid at - * any time after that point (due to a wakeup from another source). - */ - list_del_init(&waiter->list); - tsk = waiter->task; - mb(); - waiter->task = NULL; - wake_up_process(tsk); - put_task_struct(tsk); - - semtrace(sem,"Leaving __up"); -} - -EXPORT_SYMBOL(__up); |