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-rw-r--r--arch/v850/kernel/Makefile2
-rw-r--r--arch/v850/kernel/semaphore.c166
-rw-r--r--arch/v850/kernel/v850_ksyms.c7
3 files changed, 1 insertions, 174 deletions
diff --git a/arch/v850/kernel/Makefile b/arch/v850/kernel/Makefile
index 3930482bddc4..da5889c53576 100644
--- a/arch/v850/kernel/Makefile
+++ b/arch/v850/kernel/Makefile
@@ -11,7 +11,7 @@
11 11
12extra-y := head.o init_task.o vmlinux.lds 12extra-y := head.o init_task.o vmlinux.lds
13 13
14obj-y += intv.o entry.o process.o syscalls.o time.o semaphore.o setup.o \ 14obj-y += intv.o entry.o process.o syscalls.o time.o setup.o \
15 signal.o irq.o mach.o ptrace.o bug.o 15 signal.o irq.o mach.o ptrace.o bug.o
16obj-$(CONFIG_MODULES) += module.o v850_ksyms.o 16obj-$(CONFIG_MODULES) += module.o v850_ksyms.o
17# chip-specific code 17# chip-specific code
diff --git a/arch/v850/kernel/semaphore.c b/arch/v850/kernel/semaphore.c
deleted file mode 100644
index fc89fd661c99..000000000000
--- a/arch/v850/kernel/semaphore.c
+++ /dev/null
@@ -1,166 +0,0 @@
1/*
2 * arch/v850/kernel/semaphore.c -- Semaphore support
3 *
4 * Copyright (C) 1998-2000 IBM Corporation
5 * Copyright (C) 1999 Linus Torvalds
6 *
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file COPYING in the main directory of this
9 * archive for more details.
10 *
11 * This file is a copy of the s390 version, arch/s390/kernel/semaphore.c
12 * Author(s): Martin Schwidefsky
13 * which was derived from the i386 version, linux/arch/i386/kernel/semaphore.c
14 */
15
16#include <linux/errno.h>
17#include <linux/sched.h>
18#include <linux/init.h>
19
20#include <asm/semaphore.h>
21
22/*
23 * Semaphores are implemented using a two-way counter:
24 * The "count" variable is decremented for each process
25 * that tries to acquire the semaphore, while the "sleeping"
26 * variable is a count of such acquires.
27 *
28 * Notably, the inline "up()" and "down()" functions can
29 * efficiently test if they need to do any extra work (up
30 * needs to do something only if count was negative before
31 * the increment operation.
32 *
33 * "sleeping" and the contention routine ordering is
34 * protected by the semaphore spinlock.
35 *
36 * Note that these functions are only called when there is
37 * contention on the lock, and as such all this is the
38 * "non-critical" part of the whole semaphore business. The
39 * critical part is the inline stuff in <asm/semaphore.h>
40 * where we want to avoid any extra jumps and calls.
41 */
42
43/*
44 * Logic:
45 * - only on a boundary condition do we need to care. When we go
46 * from a negative count to a non-negative, we wake people up.
47 * - when we go from a non-negative count to a negative do we
48 * (a) synchronize with the "sleeper" count and (b) make sure
49 * that we're on the wakeup list before we synchronize so that
50 * we cannot lose wakeup events.
51 */
52
53void __up(struct semaphore *sem)
54{
55 wake_up(&sem->wait);
56}
57
58static DEFINE_SPINLOCK(semaphore_lock);
59
60void __sched __down(struct semaphore * sem)
61{
62 struct task_struct *tsk = current;
63 DECLARE_WAITQUEUE(wait, tsk);
64 tsk->state = TASK_UNINTERRUPTIBLE;
65 add_wait_queue_exclusive(&sem->wait, &wait);
66
67 spin_lock_irq(&semaphore_lock);
68 sem->sleepers++;
69 for (;;) {
70 int sleepers = sem->sleepers;
71
72 /*
73 * Add "everybody else" into it. They aren't
74 * playing, because we own the spinlock.
75 */
76 if (!atomic_add_negative(sleepers - 1, &sem->count)) {
77 sem->sleepers = 0;
78 break;
79 }
80 sem->sleepers = 1; /* us - see -1 above */
81 spin_unlock_irq(&semaphore_lock);
82
83 schedule();
84 tsk->state = TASK_UNINTERRUPTIBLE;
85 spin_lock_irq(&semaphore_lock);
86 }
87 spin_unlock_irq(&semaphore_lock);
88 remove_wait_queue(&sem->wait, &wait);
89 tsk->state = TASK_RUNNING;
90 wake_up(&sem->wait);
91}
92
93int __sched __down_interruptible(struct semaphore * sem)
94{
95 int retval = 0;
96 struct task_struct *tsk = current;
97 DECLARE_WAITQUEUE(wait, tsk);
98 tsk->state = TASK_INTERRUPTIBLE;
99 add_wait_queue_exclusive(&sem->wait, &wait);
100
101 spin_lock_irq(&semaphore_lock);
102 sem->sleepers ++;
103 for (;;) {
104 int sleepers = sem->sleepers;
105
106 /*
107 * With signals pending, this turns into
108 * the trylock failure case - we won't be
109 * sleeping, and we* can't get the lock as
110 * it has contention. Just correct the count
111 * and exit.
112 */
113 if (signal_pending(current)) {
114 retval = -EINTR;
115 sem->sleepers = 0;
116 atomic_add(sleepers, &sem->count);
117 break;
118 }
119
120 /*
121 * Add "everybody else" into it. They aren't
122 * playing, because we own the spinlock. The
123 * "-1" is because we're still hoping to get
124 * the lock.
125 */
126 if (!atomic_add_negative(sleepers - 1, &sem->count)) {
127 sem->sleepers = 0;
128 break;
129 }
130 sem->sleepers = 1; /* us - see -1 above */
131 spin_unlock_irq(&semaphore_lock);
132
133 schedule();
134 tsk->state = TASK_INTERRUPTIBLE;
135 spin_lock_irq(&semaphore_lock);
136 }
137 spin_unlock_irq(&semaphore_lock);
138 tsk->state = TASK_RUNNING;
139 remove_wait_queue(&sem->wait, &wait);
140 wake_up(&sem->wait);
141 return retval;
142}
143
144/*
145 * Trylock failed - make sure we correct for
146 * having decremented the count.
147 */
148int __down_trylock(struct semaphore * sem)
149{
150 unsigned long flags;
151 int sleepers;
152
153 spin_lock_irqsave(&semaphore_lock, flags);
154 sleepers = sem->sleepers + 1;
155 sem->sleepers = 0;
156
157 /*
158 * Add "everybody else" and us into it. They aren't
159 * playing, because we own the spinlock.
160 */
161 if (!atomic_add_negative(sleepers, &sem->count))
162 wake_up(&sem->wait);
163
164 spin_unlock_irqrestore(&semaphore_lock, flags);
165 return 1;
166}
diff --git a/arch/v850/kernel/v850_ksyms.c b/arch/v850/kernel/v850_ksyms.c
index 93575fdc874d..8d386a5dbc4a 100644
--- a/arch/v850/kernel/v850_ksyms.c
+++ b/arch/v850/kernel/v850_ksyms.c
@@ -11,7 +11,6 @@
11#include <asm/pgalloc.h> 11#include <asm/pgalloc.h>
12#include <asm/irq.h> 12#include <asm/irq.h>
13#include <asm/io.h> 13#include <asm/io.h>
14#include <asm/semaphore.h>
15#include <asm/checksum.h> 14#include <asm/checksum.h>
16#include <asm/current.h> 15#include <asm/current.h>
17 16
@@ -34,12 +33,6 @@ EXPORT_SYMBOL (memset);
34EXPORT_SYMBOL (memcpy); 33EXPORT_SYMBOL (memcpy);
35EXPORT_SYMBOL (memmove); 34EXPORT_SYMBOL (memmove);
36 35
37/* semaphores */
38EXPORT_SYMBOL (__down);
39EXPORT_SYMBOL (__down_interruptible);
40EXPORT_SYMBOL (__down_trylock);
41EXPORT_SYMBOL (__up);
42
43/* 36/*
44 * libgcc functions - functions that are used internally by the 37 * libgcc functions - functions that are used internally by the
45 * compiler... (prototypes are not correct though, but that 38 * compiler... (prototypes are not correct though, but that
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-17 18:03:41 -0500