1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
/*
* arch/sh/kernel/smp.c
*
* SMP support for the SuperH processors.
*
* Copyright (C) 2002, 2003 Paul Mundt
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/err.h>
#include <linux/cache.h>
#include <linux/cpumask.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/threads.h>
#include <linux/module.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <asm/atomic.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
#include <asm/smp.h>
/*
* This was written with the Sega Saturn (SMP SH-2 7604) in mind,
* but is designed to be usable regardless if there's an MMU
* present or not.
*/
struct sh_cpuinfo cpu_data[NR_CPUS];
extern void per_cpu_trap_init(void);
cpumask_t cpu_possible_map;
EXPORT_SYMBOL(cpu_possible_map);
cpumask_t cpu_online_map;
EXPORT_SYMBOL(cpu_online_map);
static atomic_t cpus_booted = ATOMIC_INIT(0);
/* These are defined by the board-specific code. */
/*
* Cause the function described by call_data to be executed on the passed
* cpu. When the function has finished, increment the finished field of
* call_data.
*/
void __smp_send_ipi(unsigned int cpu, unsigned int action);
/*
* Find the number of available processors
*/
unsigned int __smp_probe_cpus(void);
/*
* Start a particular processor
*/
void __smp_slave_init(unsigned int cpu);
/*
* Run specified function on a particular processor.
*/
void __smp_call_function(unsigned int cpu);
static inline void __init smp_store_cpu_info(unsigned int cpu)
{
cpu_data[cpu].loops_per_jiffy = loops_per_jiffy;
}
void __init smp_prepare_cpus(unsigned int max_cpus)
{
unsigned int cpu = smp_processor_id();
int i;
atomic_set(&cpus_booted, 1);
smp_store_cpu_info(cpu);
for (i = 0; i < __smp_probe_cpus(); i++)
cpu_set(i, cpu_possible_map);
}
void __devinit smp_prepare_boot_cpu(void)
{
unsigned int cpu = smp_processor_id();
cpu_set(cpu, cpu_online_map);
cpu_set(cpu, cpu_possible_map);
}
int __cpu_up(unsigned int cpu)
{
struct task_struct *tsk;
tsk = fork_idle(cpu);
if (IS_ERR(tsk))
panic("Failed forking idle task for cpu %d\n", cpu);
task_thread_info(tsk)->cpu = cpu;
cpu_set(cpu, cpu_online_map);
return 0;
}
int start_secondary(void *unused)
{
unsigned int cpu;
cpu = smp_processor_id();
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
smp_store_cpu_info(cpu);
__smp_slave_init(cpu);
preempt_disable();
per_cpu_trap_init();
atomic_inc(&cpus_booted);
cpu_idle();
return 0;
}
void __init smp_cpus_done(unsigned int max_cpus)
{
smp_mb();
}
void smp_send_reschedule(int cpu)
{
__smp_send_ipi(cpu, SMP_MSG_RESCHEDULE);
}
static void stop_this_cpu(void *unused)
{
cpu_clear(smp_processor_id(), cpu_online_map);
local_irq_disable();
for (;;)
cpu_relax();
}
void smp_send_stop(void)
{
smp_call_function(stop_this_cpu, 0, 1, 0);
}
struct smp_fn_call_struct smp_fn_call = {
.lock = SPIN_LOCK_UNLOCKED,
.finished = ATOMIC_INIT(0),
};
/*
* The caller of this wants the passed function to run on every cpu. If wait
* is set, wait until all cpus have finished the function before returning.
* The lock is here to protect the call structure.
* You must not call this function with disabled interrupts or from a
* hardware interrupt handler or from a bottom half handler.
*/
int smp_call_function(void (*func)(void *info), void *info, int retry, int wait)
{
unsigned int nr_cpus = atomic_read(&cpus_booted);
int i;
if (nr_cpus < 2)
return 0;
/* Can deadlock when called with interrupts disabled */
WARN_ON(irqs_disabled());
spin_lock(&smp_fn_call.lock);
atomic_set(&smp_fn_call.finished, 0);
smp_fn_call.fn = func;
smp_fn_call.data = info;
for (i = 0; i < nr_cpus; i++)
if (i != smp_processor_id())
__smp_call_function(i);
if (wait)
while (atomic_read(&smp_fn_call.finished) != (nr_cpus - 1));
spin_unlock(&smp_fn_call.lock);
return 0;
}
/* Not really SMP stuff ... */
int setup_profiling_timer(unsigned int multiplier)
{
return 0;
}
|
