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1#ifndef __LINUX_SMP_H
2#define __LINUX_SMP_H
3
4/*
5 * Generic SMP support
6 * Alan Cox. <alan@redhat.com>
7 */
8
9#include <linux/errno.h>
10#include <linux/types.h>
11#include <linux/list.h>
12#include <linux/cpumask.h>
13#include <linux/init.h>
14
15extern void cpu_idle(void);
16
17typedef void (*smp_call_func_t)(void *info);
18struct call_single_data {
19 struct list_head list;
20 smp_call_func_t func;
21 void *info;
22 u16 flags;
23 u16 priv;
24};
25
26/* total number of cpus in this system (may exceed NR_CPUS) */
27extern unsigned int total_cpus;
28
29int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
30 int wait);
31
32#ifdef CONFIG_SMP
33
34#include <linux/preempt.h>
35#include <linux/kernel.h>
36#include <linux/compiler.h>
37#include <linux/thread_info.h>
38#include <asm/smp.h>
39
40/*
41 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
42 * (defined in asm header):
43 */
44
45/*
46 * stops all CPUs but the current one:
47 */
48extern void smp_send_stop(void);
49
50/*
51 * sends a 'reschedule' event to another CPU:
52 */
53extern void smp_send_reschedule(int cpu);
54
55
56/*
57 * Prepare machine for booting other CPUs.
58 */
59extern void smp_prepare_cpus(unsigned int max_cpus);
60
61/*
62 * Bring a CPU up
63 */
64extern int __cpu_up(unsigned int cpunum);
65
66/*
67 * Final polishing of CPUs
68 */
69extern void smp_cpus_done(unsigned int max_cpus);
70
71/*
72 * Call a function on all other processors
73 */
74int smp_call_function(smp_call_func_t func, void *info, int wait);
75void smp_call_function_many(const struct cpumask *mask,
76 smp_call_func_t func, void *info, bool wait);
77
78void __smp_call_function_single(int cpuid, struct call_single_data *data,
79 int wait);
80
81int smp_call_function_any(const struct cpumask *mask,
82 smp_call_func_t func, void *info, int wait);
83
84/*
85 * Generic and arch helpers
86 */
87#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
88void __init call_function_init(void);
89void generic_smp_call_function_single_interrupt(void);
90void generic_smp_call_function_interrupt(void);
91void ipi_call_lock(void);
92void ipi_call_unlock(void);
93void ipi_call_lock_irq(void);
94void ipi_call_unlock_irq(void);
95#else
96static inline void call_function_init(void) { }
97#endif
98
99/*
100 * Call a function on all processors
101 */
102int on_each_cpu(smp_call_func_t func, void *info, int wait);
103
104/*
105 * Mark the boot cpu "online" so that it can call console drivers in
106 * printk() and can access its per-cpu storage.
107 */
108void smp_prepare_boot_cpu(void);
109
110extern unsigned int setup_max_cpus;
111extern void __init setup_nr_cpu_ids(void);
112extern void __init smp_init(void);
113
114#else /* !SMP */
115
116static inline void smp_send_stop(void) { }
117
118/*
119 * These macros fold the SMP functionality into a single CPU system
120 */
121#define raw_smp_processor_id() 0
122static inline int up_smp_call_function(smp_call_func_t func, void *info)
123{
124 return 0;
125}
126#define smp_call_function(func, info, wait) \
127 (up_smp_call_function(func, info))
128#define on_each_cpu(func,info,wait) \
129 ({ \
130 local_irq_disable(); \
131 func(info); \
132 local_irq_enable(); \
133 0; \
134 })
135static inline void smp_send_reschedule(int cpu) { }
136#define num_booting_cpus() 1
137#define smp_prepare_boot_cpu() do {} while (0)
138#define smp_call_function_many(mask, func, info, wait) \
139 (up_smp_call_function(func, info))
140static inline void call_function_init(void) { }
141
142static inline int
143smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
144 void *info, int wait)
145{
146 return smp_call_function_single(0, func, info, wait);
147}
148
149#endif /* !SMP */
150
151/*
152 * smp_processor_id(): get the current CPU ID.
153 *
154 * if DEBUG_PREEMPT is enabled then we check whether it is
155 * used in a preemption-safe way. (smp_processor_id() is safe
156 * if it's used in a preemption-off critical section, or in
157 * a thread that is bound to the current CPU.)
158 *
159 * NOTE: raw_smp_processor_id() is for internal use only
160 * (smp_processor_id() is the preferred variant), but in rare
161 * instances it might also be used to turn off false positives
162 * (i.e. smp_processor_id() use that the debugging code reports but
163 * which use for some reason is legal). Don't use this to hack around
164 * the warning message, as your code might not work under PREEMPT.
165 */
166#ifdef CONFIG_DEBUG_PREEMPT
167 extern unsigned int debug_smp_processor_id(void);
168# define smp_processor_id() debug_smp_processor_id()
169#else
170# define smp_processor_id() raw_smp_processor_id()
171#endif
172
173#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
174#define put_cpu() preempt_enable()
175
176/*
177 * Callback to arch code if there's nosmp or maxcpus=0 on the
178 * boot command line:
179 */
180extern void arch_disable_smp_support(void);
181
182void smp_setup_processor_id(void);
183
184#endif /* __LINUX_SMP_H */