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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#include <linux/llist.h>
15
16typedef void (*smp_call_func_t)(void *info);
17struct call_single_data {
18 struct llist_node llist;
19 smp_call_func_t func;
20 void *info;
21 u16 flags;
22};
23
24/* total number of cpus in this system (may exceed NR_CPUS) */
25extern unsigned int total_cpus;
26
27int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
28 int wait);
29
30/*
31 * Call a function on all processors
32 */
33int on_each_cpu(smp_call_func_t func, void *info, int wait);
34
35/*
36 * Call a function on processors specified by mask, which might include
37 * the local one.
38 */
39void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
40 void *info, bool wait);
41
42/*
43 * Call a function on each processor for which the supplied function
44 * cond_func returns a positive value. This may include the local
45 * processor.
46 */
47void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
48 smp_call_func_t func, void *info, bool wait,
49 gfp_t gfp_flags);
50
51int smp_call_function_single_async(int cpu, struct call_single_data *csd);
52
53#ifdef CONFIG_SMP
54
55#include <linux/preempt.h>
56#include <linux/kernel.h>
57#include <linux/compiler.h>
58#include <linux/thread_info.h>
59#include <asm/smp.h>
60
61/*
62 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
63 * (defined in asm header):
64 */
65
66/*
67 * stops all CPUs but the current one:
68 */
69extern void smp_send_stop(void);
70
71/*
72 * sends a 'reschedule' event to another CPU:
73 */
74extern void smp_send_reschedule(int cpu);
75
76
77/*
78 * Prepare machine for booting other CPUs.
79 */
80extern void smp_prepare_cpus(unsigned int max_cpus);
81
82/*
83 * Bring a CPU up
84 */
85extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
86
87/*
88 * Final polishing of CPUs
89 */
90extern void smp_cpus_done(unsigned int max_cpus);
91
92/*
93 * Call a function on all other processors
94 */
95int smp_call_function(smp_call_func_t func, void *info, int wait);
96void smp_call_function_many(const struct cpumask *mask,
97 smp_call_func_t func, void *info, bool wait);
98
99int smp_call_function_any(const struct cpumask *mask,
100 smp_call_func_t func, void *info, int wait);
101
102void kick_all_cpus_sync(void);
103void wake_up_all_idle_cpus(void);
104
105/*
106 * Generic and arch helpers
107 */
108void __init call_function_init(void);
109void generic_smp_call_function_single_interrupt(void);
110#define generic_smp_call_function_interrupt \
111 generic_smp_call_function_single_interrupt
112
113/*
114 * Mark the boot cpu "online" so that it can call console drivers in
115 * printk() and can access its per-cpu storage.
116 */
117void smp_prepare_boot_cpu(void);
118
119extern unsigned int setup_max_cpus;
120extern void __init setup_nr_cpu_ids(void);
121extern void __init smp_init(void);
122
123#else /* !SMP */
124
125static inline void smp_send_stop(void) { }
126
127/*
128 * These macros fold the SMP functionality into a single CPU system
129 */
130#define raw_smp_processor_id() 0
131static inline int up_smp_call_function(smp_call_func_t func, void *info)
132{
133 return 0;
134}
135#define smp_call_function(func, info, wait) \
136 (up_smp_call_function(func, info))
137
138static inline void smp_send_reschedule(int cpu) { }
139#define smp_prepare_boot_cpu() do {} while (0)
140#define smp_call_function_many(mask, func, info, wait) \
141 (up_smp_call_function(func, info))
142static inline void call_function_init(void) { }
143
144static inline int
145smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
146 void *info, int wait)
147{
148 return smp_call_function_single(0, func, info, wait);
149}
150
151static inline void kick_all_cpus_sync(void) { }
152static inline void wake_up_all_idle_cpus(void) { }
153
154#endif /* !SMP */
155
156/*
157 * smp_processor_id(): get the current CPU ID.
158 *
159 * if DEBUG_PREEMPT is enabled then we check whether it is
160 * used in a preemption-safe way. (smp_processor_id() is safe
161 * if it's used in a preemption-off critical section, or in
162 * a thread that is bound to the current CPU.)
163 *
164 * NOTE: raw_smp_processor_id() is for internal use only
165 * (smp_processor_id() is the preferred variant), but in rare
166 * instances it might also be used to turn off false positives
167 * (i.e. smp_processor_id() use that the debugging code reports but
168 * which use for some reason is legal). Don't use this to hack around
169 * the warning message, as your code might not work under PREEMPT.
170 */
171#ifdef CONFIG_DEBUG_PREEMPT
172 extern unsigned int debug_smp_processor_id(void);
173# define smp_processor_id() debug_smp_processor_id()
174#else
175# define smp_processor_id() raw_smp_processor_id()
176#endif
177
178#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
179#define put_cpu() preempt_enable()
180
181/*
182 * Callback to arch code if there's nosmp or maxcpus=0 on the
183 * boot command line:
184 */
185extern void arch_disable_smp_support(void);
186
187extern void arch_enable_nonboot_cpus_begin(void);
188extern void arch_enable_nonboot_cpus_end(void);
189
190void smp_setup_processor_id(void);
191
192#endif /* __LINUX_SMP_H */