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-rw-r--r--arch/powerpc/kernel/Makefile2
-rw-r--r--arch/powerpc/kernel/ppc_ksyms.c1
-rw-r--r--arch/powerpc/kernel/semaphore.c135
3 files changed, 1 insertions, 137 deletions
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index c1baf9d5903f..b9dbfff9afe9 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -12,7 +12,7 @@ CFLAGS_prom_init.o += -fPIC
12CFLAGS_btext.o += -fPIC 12CFLAGS_btext.o += -fPIC
13endif 13endif
14 14
15obj-y := semaphore.o cputable.o ptrace.o syscalls.o \ 15obj-y := cputable.o ptrace.o syscalls.o \
16 irq.o align.o signal_32.o pmc.o vdso.o \ 16 irq.o align.o signal_32.o pmc.o vdso.o \
17 init_task.o process.o systbl.o idle.o \ 17 init_task.o process.o systbl.o idle.o \
18 signal.o 18 signal.o
diff --git a/arch/powerpc/kernel/ppc_ksyms.c b/arch/powerpc/kernel/ppc_ksyms.c
index 9c98424277a8..65d14e6ddc3c 100644
--- a/arch/powerpc/kernel/ppc_ksyms.c
+++ b/arch/powerpc/kernel/ppc_ksyms.c
@@ -15,7 +15,6 @@
15#include <linux/bitops.h> 15#include <linux/bitops.h>
16 16
17#include <asm/page.h> 17#include <asm/page.h>
18#include <asm/semaphore.h>
19#include <asm/processor.h> 18#include <asm/processor.h>
20#include <asm/cacheflush.h> 19#include <asm/cacheflush.h>
21#include <asm/uaccess.h> 20#include <asm/uaccess.h>
diff --git a/arch/powerpc/kernel/semaphore.c b/arch/powerpc/kernel/semaphore.c
deleted file mode 100644
index 2f8c3c951394..000000000000
--- a/arch/powerpc/kernel/semaphore.c
+++ /dev/null
@@ -1,135 +0,0 @@
1/*
2 * PowerPC-specific semaphore code.
3 *
4 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * April 2001 - Reworked by Paul Mackerras <paulus@samba.org>
12 * to eliminate the SMP races in the old version between the updates
13 * of `count' and `waking'. Now we use negative `count' values to
14 * indicate that some process(es) are waiting for the semaphore.
15 */
16
17#include <linux/sched.h>
18#include <linux/init.h>
19#include <linux/module.h>
20
21#include <asm/atomic.h>
22#include <asm/semaphore.h>
23#include <asm/errno.h>
24
25/*
26 * Atomically update sem->count.
27 * This does the equivalent of the following:
28 *
29 * old_count = sem->count;
30 * tmp = MAX(old_count, 0) + incr;
31 * sem->count = tmp;
32 * return old_count;
33 */
34static inline int __sem_update_count(struct semaphore *sem, int incr)
35{
36 int old_count, tmp;
37
38 __asm__ __volatile__("\n"
39"1: lwarx %0,0,%3\n"
40" srawi %1,%0,31\n"
41" andc %1,%0,%1\n"
42" add %1,%1,%4\n"
43 PPC405_ERR77(0,%3)
44" stwcx. %1,0,%3\n"
45" bne 1b"
46 : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count)
47 : "r" (&sem->count), "r" (incr), "m" (sem->count)
48 : "cc");
49
50 return old_count;
51}
52
53void __up(struct semaphore *sem)
54{
55 /*
56 * Note that we incremented count in up() before we came here,
57 * but that was ineffective since the result was <= 0, and
58 * any negative value of count is equivalent to 0.
59 * This ends up setting count to 1, unless count is now > 0
60 * (i.e. because some other cpu has called up() in the meantime),
61 * in which case we just increment count.
62 */
63 __sem_update_count(sem, 1);
64 wake_up(&sem->wait);
65}
66EXPORT_SYMBOL(__up);
67
68/*
69 * Note that when we come in to __down or __down_interruptible,
70 * we have already decremented count, but that decrement was
71 * ineffective since the result was < 0, and any negative value
72 * of count is equivalent to 0.
73 * Thus it is only when we decrement count from some value > 0
74 * that we have actually got the semaphore.
75 */
76void __sched __down(struct semaphore *sem)
77{
78 struct task_struct *tsk = current;
79 DECLARE_WAITQUEUE(wait, tsk);
80
81 __set_task_state(tsk, TASK_UNINTERRUPTIBLE);
82 add_wait_queue_exclusive(&sem->wait, &wait);
83
84 /*
85 * Try to get the semaphore. If the count is > 0, then we've
86 * got the semaphore; we decrement count and exit the loop.
87 * If the count is 0 or negative, we set it to -1, indicating
88 * that we are asleep, and then sleep.
89 */
90 while (__sem_update_count(sem, -1) <= 0) {
91 schedule();
92 set_task_state(tsk, TASK_UNINTERRUPTIBLE);
93 }
94 remove_wait_queue(&sem->wait, &wait);
95 __set_task_state(tsk, TASK_RUNNING);
96
97 /*
98 * If there are any more sleepers, wake one of them up so
99 * that it can either get the semaphore, or set count to -1
100 * indicating that there are still processes sleeping.
101 */
102 wake_up(&sem->wait);
103}
104EXPORT_SYMBOL(__down);
105
106int __sched __down_interruptible(struct semaphore * sem)
107{
108 int retval = 0;
109 struct task_struct *tsk = current;
110 DECLARE_WAITQUEUE(wait, tsk);
111
112 __set_task_state(tsk, TASK_INTERRUPTIBLE);
113 add_wait_queue_exclusive(&sem->wait, &wait);
114
115 while (__sem_update_count(sem, -1) <= 0) {
116 if (signal_pending(current)) {
117 /*
118 * A signal is pending - give up trying.
119 * Set sem->count to 0 if it is negative,
120 * since we are no longer sleeping.
121 */
122 __sem_update_count(sem, 0);
123 retval = -EINTR;
124 break;
125 }
126 schedule();
127 set_task_state(tsk, TASK_INTERRUPTIBLE);
128 }
129 remove_wait_queue(&sem->wait, &wait);
130 __set_task_state(tsk, TASK_RUNNING);
131
132 wake_up(&sem->wait);
133 return retval;
134}
135EXPORT_SYMBOL(__down_interruptible);
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