diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/kernel/smp.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/sh/kernel/smp.c')
-rw-r--r-- | arch/sh/kernel/smp.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c new file mode 100644 index 000000000000..56a39d69e080 --- /dev/null +++ b/arch/sh/kernel/smp.c | |||
@@ -0,0 +1,199 @@ | |||
1 | /* | ||
2 | * arch/sh/kernel/smp.c | ||
3 | * | ||
4 | * SMP support for the SuperH processors. | ||
5 | * | ||
6 | * Copyright (C) 2002, 2003 Paul Mundt | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify it | ||
9 | * under the terms of the GNU General Public License as published by the | ||
10 | * Free Software Foundation; either version 2 of the License, or (at your | ||
11 | * option) any later version. | ||
12 | */ | ||
13 | #include <linux/config.h> | ||
14 | #include <linux/cache.h> | ||
15 | #include <linux/cpumask.h> | ||
16 | #include <linux/delay.h> | ||
17 | #include <linux/init.h> | ||
18 | #include <linux/interrupt.h> | ||
19 | #include <linux/spinlock.h> | ||
20 | #include <linux/threads.h> | ||
21 | #include <linux/module.h> | ||
22 | #include <linux/time.h> | ||
23 | #include <linux/timex.h> | ||
24 | #include <linux/sched.h> | ||
25 | |||
26 | #include <asm/atomic.h> | ||
27 | #include <asm/processor.h> | ||
28 | #include <asm/system.h> | ||
29 | #include <asm/mmu_context.h> | ||
30 | #include <asm/smp.h> | ||
31 | |||
32 | /* | ||
33 | * This was written with the Sega Saturn (SMP SH-2 7604) in mind, | ||
34 | * but is designed to be usable regardless if there's an MMU | ||
35 | * present or not. | ||
36 | */ | ||
37 | struct sh_cpuinfo cpu_data[NR_CPUS]; | ||
38 | |||
39 | extern void per_cpu_trap_init(void); | ||
40 | |||
41 | cpumask_t cpu_possible_map; | ||
42 | cpumask_t cpu_online_map; | ||
43 | static atomic_t cpus_booted = ATOMIC_INIT(0); | ||
44 | |||
45 | /* These are defined by the board-specific code. */ | ||
46 | |||
47 | /* | ||
48 | * Cause the function described by call_data to be executed on the passed | ||
49 | * cpu. When the function has finished, increment the finished field of | ||
50 | * call_data. | ||
51 | */ | ||
52 | void __smp_send_ipi(unsigned int cpu, unsigned int action); | ||
53 | |||
54 | /* | ||
55 | * Find the number of available processors | ||
56 | */ | ||
57 | unsigned int __smp_probe_cpus(void); | ||
58 | |||
59 | /* | ||
60 | * Start a particular processor | ||
61 | */ | ||
62 | void __smp_slave_init(unsigned int cpu); | ||
63 | |||
64 | /* | ||
65 | * Run specified function on a particular processor. | ||
66 | */ | ||
67 | void __smp_call_function(unsigned int cpu); | ||
68 | |||
69 | static inline void __init smp_store_cpu_info(unsigned int cpu) | ||
70 | { | ||
71 | cpu_data[cpu].loops_per_jiffy = loops_per_jiffy; | ||
72 | } | ||
73 | |||
74 | void __init smp_prepare_cpus(unsigned int max_cpus) | ||
75 | { | ||
76 | unsigned int cpu = smp_processor_id(); | ||
77 | int i; | ||
78 | |||
79 | atomic_set(&cpus_booted, 1); | ||
80 | smp_store_cpu_info(cpu); | ||
81 | |||
82 | for (i = 0; i < __smp_probe_cpus(); i++) | ||
83 | cpu_set(i, cpu_possible_map); | ||
84 | } | ||
85 | |||
86 | void __devinit smp_prepare_boot_cpu(void) | ||
87 | { | ||
88 | unsigned int cpu = smp_processor_id(); | ||
89 | |||
90 | cpu_set(cpu, cpu_online_map); | ||
91 | cpu_set(cpu, cpu_possible_map); | ||
92 | } | ||
93 | |||
94 | int __cpu_up(unsigned int cpu) | ||
95 | { | ||
96 | struct task_struct *tsk; | ||
97 | |||
98 | tsk = fork_idle(cpu); | ||
99 | |||
100 | if (IS_ERR(tsk)) | ||
101 | panic("Failed forking idle task for cpu %d\n", cpu); | ||
102 | |||
103 | tsk->thread_info->cpu = cpu; | ||
104 | |||
105 | cpu_set(cpu, cpu_online_map); | ||
106 | |||
107 | return 0; | ||
108 | } | ||
109 | |||
110 | int start_secondary(void *unused) | ||
111 | { | ||
112 | unsigned int cpu = smp_processor_id(); | ||
113 | |||
114 | atomic_inc(&init_mm.mm_count); | ||
115 | current->active_mm = &init_mm; | ||
116 | |||
117 | smp_store_cpu_info(cpu); | ||
118 | |||
119 | __smp_slave_init(cpu); | ||
120 | per_cpu_trap_init(); | ||
121 | |||
122 | atomic_inc(&cpus_booted); | ||
123 | |||
124 | cpu_idle(); | ||
125 | return 0; | ||
126 | } | ||
127 | |||
128 | void __init smp_cpus_done(unsigned int max_cpus) | ||
129 | { | ||
130 | smp_mb(); | ||
131 | } | ||
132 | |||
133 | void smp_send_reschedule(int cpu) | ||
134 | { | ||
135 | __smp_send_ipi(cpu, SMP_MSG_RESCHEDULE); | ||
136 | } | ||
137 | |||
138 | static void stop_this_cpu(void *unused) | ||
139 | { | ||
140 | cpu_clear(smp_processor_id(), cpu_online_map); | ||
141 | local_irq_disable(); | ||
142 | |||
143 | for (;;) | ||
144 | cpu_relax(); | ||
145 | } | ||
146 | |||
147 | void smp_send_stop(void) | ||
148 | { | ||
149 | smp_call_function(stop_this_cpu, 0, 1, 0); | ||
150 | } | ||
151 | |||
152 | |||
153 | struct smp_fn_call_struct smp_fn_call = { | ||
154 | .lock = SPIN_LOCK_UNLOCKED, | ||
155 | .finished = ATOMIC_INIT(0), | ||
156 | }; | ||
157 | |||
158 | /* | ||
159 | * The caller of this wants the passed function to run on every cpu. If wait | ||
160 | * is set, wait until all cpus have finished the function before returning. | ||
161 | * The lock is here to protect the call structure. | ||
162 | * You must not call this function with disabled interrupts or from a | ||
163 | * hardware interrupt handler or from a bottom half handler. | ||
164 | */ | ||
165 | int smp_call_function(void (*func)(void *info), void *info, int retry, int wait) | ||
166 | { | ||
167 | unsigned int nr_cpus = atomic_read(&cpus_booted); | ||
168 | int i; | ||
169 | |||
170 | if (nr_cpus < 2) | ||
171 | return 0; | ||
172 | |||
173 | /* Can deadlock when called with interrupts disabled */ | ||
174 | WARN_ON(irqs_disabled()); | ||
175 | |||
176 | spin_lock(&smp_fn_call.lock); | ||
177 | |||
178 | atomic_set(&smp_fn_call.finished, 0); | ||
179 | smp_fn_call.fn = func; | ||
180 | smp_fn_call.data = info; | ||
181 | |||
182 | for (i = 0; i < nr_cpus; i++) | ||
183 | if (i != smp_processor_id()) | ||
184 | __smp_call_function(i); | ||
185 | |||
186 | if (wait) | ||
187 | while (atomic_read(&smp_fn_call.finished) != (nr_cpus - 1)); | ||
188 | |||
189 | spin_unlock(&smp_fn_call.lock); | ||
190 | |||
191 | return 0; | ||
192 | } | ||
193 | |||
194 | /* Not really SMP stuff ... */ | ||
195 | int setup_profiling_timer(unsigned int multiplier) | ||
196 | { | ||
197 | return 0; | ||
198 | } | ||
199 | |||