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-rw-r--r--arch/ia64/kernel/semaphore.c165
1 files changed, 0 insertions, 165 deletions
diff --git a/arch/ia64/kernel/semaphore.c b/arch/ia64/kernel/semaphore.c
deleted file mode 100644
index 2724ef3..0000000
--- a/arch/ia64/kernel/semaphore.c
+++ /dev/null
@@ -1,165 +0,0 @@
-/*
- * IA-64 semaphore implementation (derived from x86 version).
- *
- * Copyright (C) 1999-2000, 2002 Hewlett-Packard Co
- * David Mosberger-Tang <davidm@hpl.hp.com>
- */
-
-/*
- * Semaphores are implemented using a two-way counter: The "count"
- * variable is decremented for each process that tries to acquire the
- * semaphore, while the "sleepers" variable is a count of such
- * acquires.
- *
- * Notably, the inline "up()" and "down()" functions can efficiently
- * test if they need to do any extra work (up needs to do something
- * only if count was negative before the increment operation.
- *
- * "sleeping" and the contention routine ordering is protected
- * by the spinlock in the semaphore's waitqueue head.
- *
- * Note that these functions are only called when there is contention
- * on the lock, and as such all this is the "non-critical" part of the
- * whole semaphore business. The critical part is the inline stuff in
- * <asm/semaphore.h> where we want to avoid any extra jumps and calls.
- */
-#include <linux/sched.h>
-#include <linux/init.h>
-
-#include <asm/errno.h>
-#include <asm/semaphore.h>
-
-/*
- * Logic:
- * - Only on a boundary condition do we need to care. When we go
- * from a negative count to a non-negative, we wake people up.
- * - When we go from a non-negative count to a negative do we
- * (a) synchronize with the "sleepers" count and (b) make sure
- * that we're on the wakeup list before we synchronize so that
- * we cannot lose wakeup events.
- */
-
-void
-__up (struct semaphore *sem)
-{
- wake_up(&sem->wait);
-}
-
-void __sched __down (struct semaphore *sem)
-{
- struct task_struct *tsk = current;
- DECLARE_WAITQUEUE(wait, tsk);
- unsigned long flags;
-
- tsk->state = TASK_UNINTERRUPTIBLE;
- spin_lock_irqsave(&sem->wait.lock, flags);
- add_wait_queue_exclusive_locked(&sem->wait, &wait);
-
- sem->sleepers++;
- for (;;) {
- int sleepers = sem->sleepers;
-
- /*
- * Add "everybody else" into it. They aren't
- * playing, because we own the spinlock in
- * the wait_queue_head.
- */
- if (!atomic_add_negative(sleepers - 1, &sem->count)) {
- sem->sleepers = 0;
- break;
- }
- sem->sleepers = 1; /* us - see -1 above */
- spin_unlock_irqrestore(&sem->wait.lock, flags);
-
- schedule();
-
- spin_lock_irqsave(&sem->wait.lock, flags);
- tsk->state = TASK_UNINTERRUPTIBLE;
- }
- remove_wait_queue_locked(&sem->wait, &wait);
- wake_up_locked(&sem->wait);
- spin_unlock_irqrestore(&sem->wait.lock, flags);
- tsk->state = TASK_RUNNING;
-}
-
-int __sched __down_interruptible (struct semaphore * sem)
-{
- int retval = 0;
- struct task_struct *tsk = current;
- DECLARE_WAITQUEUE(wait, tsk);
- unsigned long flags;
-
- tsk->state = TASK_INTERRUPTIBLE;
- spin_lock_irqsave(&sem->wait.lock, flags);
- add_wait_queue_exclusive_locked(&sem->wait, &wait);
-
- sem->sleepers ++;
- for (;;) {
- int sleepers = sem->sleepers;
-
- /*
- * With signals pending, this turns into
- * the trylock failure case - we won't be
- * sleeping, and we* can't get the lock as
- * it has contention. Just correct the count
- * and exit.
- */
- if (signal_pending(current)) {
- retval = -EINTR;
- sem->sleepers = 0;
- atomic_add(sleepers, &sem->count);
- break;
- }
-
- /*
- * Add "everybody else" into it. They aren't
- * playing, because we own the spinlock in
- * wait_queue_head. The "-1" is because we're
- * still hoping to get the semaphore.
- */
- if (!atomic_add_negative(sleepers - 1, &sem->count)) {
- sem->sleepers = 0;
- break;
- }
- sem->sleepers = 1; /* us - see -1 above */
- spin_unlock_irqrestore(&sem->wait.lock, flags);
-
- schedule();
-
- spin_lock_irqsave(&sem->wait.lock, flags);
- tsk->state = TASK_INTERRUPTIBLE;
- }
- remove_wait_queue_locked(&sem->wait, &wait);
- wake_up_locked(&sem->wait);
- spin_unlock_irqrestore(&sem->wait.lock, flags);
-
- tsk->state = TASK_RUNNING;
- return retval;
-}
-
-/*
- * Trylock failed - make sure we correct for having decremented the
- * count.
- */
-int
-__down_trylock (struct semaphore *sem)
-{
- unsigned long flags;
- int sleepers;
-
- spin_lock_irqsave(&sem->wait.lock, flags);
- sleepers = sem->sleepers + 1;
- sem->sleepers = 0;
-
- /*
- * Add "everybody else" and us into it. They aren't
- * playing, because we own the spinlock in the
- * wait_queue_head.
- */
- if (!atomic_add_negative(sleepers, &sem->count)) {
- wake_up_locked(&sem->wait);
- }
-
- spin_unlock_irqrestore(&sem->wait.lock, flags);
- return 1;
-}
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