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-rw-r--r--arch/parisc/kernel/semaphore.c102
1 files changed, 0 insertions, 102 deletions
diff --git a/arch/parisc/kernel/semaphore.c b/arch/parisc/kernel/semaphore.c
deleted file mode 100644
index ee806bcc3726..000000000000
--- a/arch/parisc/kernel/semaphore.c
+++ /dev/null
@@ -1,102 +0,0 @@
-/*
- * Semaphore implementation Copyright (c) 2001 Matthew Wilcox, Hewlett-Packard
- */
-
-#include <linux/sched.h>
-#include <linux/spinlock.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-
-/*
- * Semaphores are complex as we wish to avoid using two variables.
- * `count' has multiple roles, depending on its value. If it is positive
- * or zero, there are no waiters. The functions here will never be
- * called; see <asm/semaphore.h>
- *
- * When count is -1 it indicates there is at least one task waiting
- * for the semaphore.
- *
- * When count is less than that, there are '- count - 1' wakeups
- * pending. ie if it has value -3, there are 2 wakeups pending.
- *
- * 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.
- */
-void __up(struct semaphore *sem)
-{
- sem->count--;
- wake_up(&sem->wait);
-}
-
-#define wakers(count) (-1 - count)
-
-#define DOWN_HEAD \
- int ret = 0; \
- DECLARE_WAITQUEUE(wait, current); \
- \
- /* Note that someone is waiting */ \
- if (sem->count == 0) \
- sem->count = -1; \
- \
- /* protected by the sentry still -- use unlocked version */ \
- wait.flags = WQ_FLAG_EXCLUSIVE; \
- __add_wait_queue_tail(&sem->wait, &wait); \
- lost_race: \
- spin_unlock_irq(&sem->sentry); \
-
-#define DOWN_TAIL \
- spin_lock_irq(&sem->sentry); \
- if (wakers(sem->count) == 0 && ret == 0) \
- goto lost_race; /* Someone stole our wakeup */ \
- __remove_wait_queue(&sem->wait, &wait); \
- current->state = TASK_RUNNING; \
- if (!waitqueue_active(&sem->wait) && (sem->count < 0)) \
- sem->count = wakers(sem->count);
-
-#define UPDATE_COUNT \
- sem->count += (sem->count < 0) ? 1 : - 1;
-
-
-void __sched __down(struct semaphore * sem)
-{
- DOWN_HEAD
-
- for(;;) {
- set_task_state(current, TASK_UNINTERRUPTIBLE);
- /* we can _read_ this without the sentry */
- if (sem->count != -1)
- break;
- schedule();
- }
-
- DOWN_TAIL
- UPDATE_COUNT
-}
-
-int __sched __down_interruptible(struct semaphore * sem)
-{
- DOWN_HEAD
-
- for(;;) {
- set_task_state(current, TASK_INTERRUPTIBLE);
- /* we can _read_ this without the sentry */
- if (sem->count != -1)
- break;
-
- if (signal_pending(current)) {
- ret = -EINTR;
- break;
- }
- schedule();
- }
-
- DOWN_TAIL
-
- if (!ret) {
- UPDATE_COUNT
- }
-
- return ret;
-}