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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};
24
25/* total number of cpus in this system (may exceed NR_CPUS) */
26extern unsigned int total_cpus;
27
28int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
29 int wait);
30
31/*
32 * Call a function on all processors
33 */
34int on_each_cpu(smp_call_func_t func, void *info, int wait);
35
36/*
37 * Call a function on processors specified by mask, which might include
38 * the local one.
39 */
40void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
41 void *info, bool wait);
42
43/*
44 * Call a function on each processor for which the supplied function
45 * cond_func returns a positive value. This may include the local
46 * processor.
47 */
48void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
49 smp_call_func_t func, void *info, bool wait,
50 gfp_t gfp_flags);
51
52#ifdef CONFIG_SMP
53
54#include <linux/preempt.h>
55#include <linux/kernel.h>
56#include <linux/compiler.h>
57#include <linux/thread_info.h>
58#include <asm/smp.h>
59
60/*
61 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
62 * (defined in asm header):
63 */
64
65/*
66 * stops all CPUs but the current one:
67 */
68extern void smp_send_stop(void);
69
70/*
71 * sends a 'reschedule' event to another CPU:
72 */
73extern void smp_send_reschedule(int cpu);
74
75
76/*
77 * Prepare machine for booting other CPUs.
78 */
79extern void smp_prepare_cpus(unsigned int max_cpus);
80
81/*
82 * Bring a CPU up
83 */
84extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
85
86/*
87 * Final polishing of CPUs
88 */
89extern void smp_cpus_done(unsigned int max_cpus);
90
91/*
92 * Call a function on all other processors
93 */
94int smp_call_function(smp_call_func_t func, void *info, int wait);
95void smp_call_function_many(const struct cpumask *mask,
96 smp_call_func_t func, void *info, bool wait);
97
98void __smp_call_function_single(int cpuid, struct call_single_data *data,
99 int wait);
100
101int smp_call_function_any(const struct cpumask *mask,
102 smp_call_func_t func, void *info, int wait);
103
104void kick_all_cpus_sync(void);
105
106/*
107 * Generic and arch helpers
108 */
109#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
110void __init call_function_init(void);
111void generic_smp_call_function_single_interrupt(void);
112#define generic_smp_call_function_interrupt \
113 generic_smp_call_function_single_interrupt
114#else
115static inline void call_function_init(void) { }
116#endif
117
118/*
119 * Mark the boot cpu "online" so that it can call console drivers in
120 * printk() and can access its per-cpu storage.
121 */
122void smp_prepare_boot_cpu(void);
123
124extern unsigned int setup_max_cpus;
125extern void __init setup_nr_cpu_ids(void);
126extern void __init smp_init(void);
127
128#else /* !SMP */
129
130static inline void smp_send_stop(void) { }
131
132/*
133 * These macros fold the SMP functionality into a single CPU system
134 */
135#define raw_smp_processor_id() 0
136static inline int up_smp_call_function(smp_call_func_t func, void *info)
137{
138 return 0;
139}
140#define smp_call_function(func, info, wait) \
141 (up_smp_call_function(func, info))
142
143static inline void smp_send_reschedule(int cpu) { }
144#define smp_prepare_boot_cpu() do {} while (0)
145#define smp_call_function_many(mask, func, info, wait) \
146 (up_smp_call_function(func, info))
147static inline void call_function_init(void) { }
148
149static inline int
150smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
151 void *info, int wait)
152{
153 return smp_call_function_single(0, func, info, wait);
154}
155
156static inline void kick_all_cpus_sync(void) { }
157
158static inline void __smp_call_function_single(int cpuid,
159 struct call_single_data *data, int wait)
160{
161 on_each_cpu(data->func, data->info, wait);
162}
163
164#endif /* !SMP */
165
166/*
167 * smp_processor_id(): get the current CPU ID.
168 *
169 * if DEBUG_PREEMPT is enabled then we check whether it is
170 * used in a preemption-safe way. (smp_processor_id() is safe
171 * if it's used in a preemption-off critical section, or in
172 * a thread that is bound to the current CPU.)
173 *
174 * NOTE: raw_smp_processor_id() is for internal use only
175 * (smp_processor_id() is the preferred variant), but in rare
176 * instances it might also be used to turn off false positives
177 * (i.e. smp_processor_id() use that the debugging code reports but
178 * which use for some reason is legal). Don't use this to hack around
179 * the warning message, as your code might not work under PREEMPT.
180 */
181#ifdef CONFIG_DEBUG_PREEMPT
182 extern unsigned int debug_smp_processor_id(void);
183# define smp_processor_id() debug_smp_processor_id()
184#else
185# define smp_processor_id() raw_smp_processor_id()
186#endif
187
188#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
189#define put_cpu() preempt_enable()
190
191/*
192 * Callback to arch code if there's nosmp or maxcpus=0 on the
193 * boot command line:
194 */
195extern void arch_disable_smp_support(void);
196
197void smp_setup_processor_id(void);
198
199#endif /* __LINUX_SMP_H */