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authorLinus Torvalds <torvalds@linux-foundation.org>2008-04-18 08:25:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-04-18 08:25:29 -0700
commitd7bb545d86825e635cab33a1dd81ca0ad7b92887 (patch)
tree34da4139ef06ceab6549aea3906639c7413978c8 /arch/s390/kernel/semaphore.c
parent75e98b34155264d943aa53edce465e87f3ccbadf (diff)
parent2342e51ba2b52a7f5b78227e6faa4603ed3632a0 (diff)
Merge branch 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: Remove DEBUG_SEMAPHORE from Kconfig Improve semaphore documentation Simplify semaphore implementation Add down_timeout and change ACPI to use it Introduce down_killable() Generic semaphore implementation Add semaphore.h to kernel_lock.c Fix quota.h includes
Diffstat (limited to 'arch/s390/kernel/semaphore.c')
-rw-r--r--arch/s390/kernel/semaphore.c108
1 files changed, 0 insertions, 108 deletions
diff --git a/arch/s390/kernel/semaphore.c b/arch/s390/kernel/semaphore.c
deleted file mode 100644
index 191303f6c1d..00000000000
--- a/arch/s390/kernel/semaphore.c
+++ /dev/null
@@ -1,108 +0,0 @@
-/*
- * linux/arch/s390/kernel/semaphore.c
- *
- * S390 version
- * Copyright (C) 1998-2000 IBM Corporation
- * Author(s): Martin Schwidefsky
- *
- * Derived from "linux/arch/i386/kernel/semaphore.c
- * Copyright (C) 1999, Linus Torvalds
- *
- */
-#include <linux/sched.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-
-#include <asm/semaphore.h>
-
-/*
- * Atomically update sem->count. Equivalent to:
- * old_val = sem->count.counter;
- * new_val = ((old_val >= 0) ? old_val : 0) + incr;
- * sem->count.counter = new_val;
- * return old_val;
- */
-static inline int __sem_update_count(struct semaphore *sem, int incr)
-{
- int old_val, new_val;
-
- asm volatile(
- " l %0,0(%3)\n"
- "0: ltr %1,%0\n"
- " jhe 1f\n"
- " lhi %1,0\n"
- "1: ar %1,%4\n"
- " cs %0,%1,0(%3)\n"
- " jl 0b\n"
- : "=&d" (old_val), "=&d" (new_val), "=m" (sem->count)
- : "a" (&sem->count), "d" (incr), "m" (sem->count)
- : "cc");
- return old_val;
-}
-
-/*
- * The inline function up() incremented count but the result
- * was <= 0. This indicates that some process is waiting on
- * the semaphore. The semaphore is free and we'll wake the
- * first sleeping process, so we set count to 1 unless some
- * other cpu has called up in the meantime in which case
- * we just increment count by 1.
- */
-void __up(struct semaphore *sem)
-{
- __sem_update_count(sem, 1);
- wake_up(&sem->wait);
-}
-
-/*
- * The inline function down() decremented count and the result
- * was < 0. The wait loop will atomically test and update the
- * semaphore counter following the rules:
- * count > 0: decrement count, wake up queue and exit.
- * count <= 0: set count to -1, go to sleep.
- */
-void __sched __down(struct semaphore * sem)
-{
- struct task_struct *tsk = current;
- DECLARE_WAITQUEUE(wait, tsk);
-
- __set_task_state(tsk, TASK_UNINTERRUPTIBLE);
- add_wait_queue_exclusive(&sem->wait, &wait);
- while (__sem_update_count(sem, -1) <= 0) {
- schedule();
- set_task_state(tsk, TASK_UNINTERRUPTIBLE);
- }
- remove_wait_queue(&sem->wait, &wait);
- __set_task_state(tsk, TASK_RUNNING);
- wake_up(&sem->wait);
-}
-
-/*
- * Same as __down() with an additional test for signals.
- * If a signal is pending the count is updated as follows:
- * count > 0: wake up queue and exit.
- * count <= 0: set count to 0, wake up queue and exit.
- */
-int __sched __down_interruptible(struct semaphore * sem)
-{
- int retval = 0;
- struct task_struct *tsk = current;
- DECLARE_WAITQUEUE(wait, tsk);
-
- __set_task_state(tsk, TASK_INTERRUPTIBLE);
- add_wait_queue_exclusive(&sem->wait, &wait);
- while (__sem_update_count(sem, -1) <= 0) {
- if (signal_pending(current)) {
- __sem_update_count(sem, 0);
- retval = -EINTR;
- break;
- }
- schedule();
- set_task_state(tsk, TASK_INTERRUPTIBLE);
- }
- remove_wait_queue(&sem->wait, &wait);
- __set_task_state(tsk, TASK_RUNNING);
- wake_up(&sem->wait);
- return retval;
-}
-