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@@ -1,140 +0,0 @@
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-/*
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- * Just taken from alpha implementation.
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- * This can't work well, perhaps.
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- */
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-/*
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- * Generic semaphore code. Buyer beware. Do your own
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- * specific changes in <asm/semaphore-helper.h>
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- */
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-
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-#include <linux/errno.h>
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-#include <linux/rwsem.h>
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-#include <linux/sched.h>
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-#include <linux/wait.h>
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-#include <linux/init.h>
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-#include <asm/semaphore.h>
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-#include <asm/semaphore-helper.h>
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-
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-spinlock_t semaphore_wake_lock;
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-
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-/*
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- * Semaphores are implemented using a two-way counter:
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- * The "count" variable is decremented for each process
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- * that tries to sleep, while the "waking" variable is
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- * incremented when the "up()" code goes to wake up waiting
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- * processes.
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- *
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- * Notably, the inline "up()" and "down()" functions can
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- * efficiently test if they need to do any extra work (up
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- * needs to do something only if count was negative before
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- * the increment operation.
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- *
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- * waking_non_zero() (from asm/semaphore.h) must execute
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- * atomically.
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- *
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- * When __up() is called, the count was negative before
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- * incrementing it, and we need to wake up somebody.
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- *
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- * This routine adds one to the count of processes that need to
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- * wake up and exit. ALL waiting processes actually wake up but
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- * only the one that gets to the "waking" field first will gate
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- * through and acquire the semaphore. The others will go back
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- * to sleep.
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- *
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- * Note that these functions are only called when there is
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- * contention on the lock, and as such all this is the
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- * "non-critical" part of the whole semaphore business. The
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- * critical part is the inline stuff in <asm/semaphore.h>
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- * where we want to avoid any extra jumps and calls.
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- */
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-void __up(struct semaphore *sem)
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-{
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- wake_one_more(sem);
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- wake_up(&sem->wait);
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-}
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-
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-/*
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- * Perform the "down" function. Return zero for semaphore acquired,
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- * return negative for signalled out of the function.
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- *
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- * If called from __down, the return is ignored and the wait loop is
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- * not interruptible. This means that a task waiting on a semaphore
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- * using "down()" cannot be killed until someone does an "up()" on
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- * the semaphore.
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- *
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- * If called from __down_interruptible, the return value gets checked
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- * upon return. If the return value is negative then the task continues
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- * with the negative value in the return register (it can be tested by
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- * the caller).
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- *
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- * Either form may be used in conjunction with "up()".
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- *
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- */
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-
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-#define DOWN_VAR \
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- struct task_struct *tsk = current; \
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- wait_queue_t wait; \
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- init_waitqueue_entry(&wait, tsk);
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-
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-#define DOWN_HEAD(task_state) \
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- \
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- \
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- tsk->state = (task_state); \
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- add_wait_queue(&sem->wait, &wait); \
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- \
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- /* \
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- * Ok, we're set up. sem->count is known to be less than zero \
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- * so we must wait. \
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- * \
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- * We can let go the lock for purposes of waiting. \
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- * We re-acquire it after awaking so as to protect \
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- * all semaphore operations. \
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- * \
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- * If "up()" is called before we call waking_non_zero() then \
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- * we will catch it right away. If it is called later then \
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- * we will have to go through a wakeup cycle to catch it. \
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- * \
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- * Multiple waiters contend for the semaphore lock to see \
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- * who gets to gate through and who has to wait some more. \
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- */ \
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- for (;;) {
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-
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-#define DOWN_TAIL(task_state) \
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- tsk->state = (task_state); \
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- } \
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- tsk->state = TASK_RUNNING; \
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- remove_wait_queue(&sem->wait, &wait);
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-
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-void __sched __down(struct semaphore * sem)
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-{
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- DOWN_VAR
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- DOWN_HEAD(TASK_UNINTERRUPTIBLE)
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- if (waking_non_zero(sem))
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- break;
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- schedule();
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- DOWN_TAIL(TASK_UNINTERRUPTIBLE)
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-}
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-
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-int __sched __down_interruptible(struct semaphore * sem)
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-{
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- int ret = 0;
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- DOWN_VAR
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- DOWN_HEAD(TASK_INTERRUPTIBLE)
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-
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- ret = waking_non_zero_interruptible(sem, tsk);
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- if (ret)
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- {
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- if (ret == 1)
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- /* ret != 0 only if we get interrupted -arca */
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- ret = 0;
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- break;
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- }
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- schedule();
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- DOWN_TAIL(TASK_INTERRUPTIBLE)
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- return ret;
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-}
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-
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-int __down_trylock(struct semaphore * sem)
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-{
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- return waking_non_zero_trylock(sem);
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-}
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