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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
14extern void cpu_idle(void);
15
16struct call_single_data {
17 struct list_head list;
18 void (*func) (void *info);
19 void *info;
20 u16 flags;
21 u16 priv;
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, void (*func) (void *info), void *info,
28 int wait);
29
30#ifdef CONFIG_SMP
31
32#include <linux/preempt.h>
33#include <linux/kernel.h>
34#include <linux/compiler.h>
35#include <linux/thread_info.h>
36#include <asm/smp.h>
37
38/*
39 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
40 * (defined in asm header):
41 */
42
43/*
44 * stops all CPUs but the current one:
45 */
46extern void smp_send_stop(void);
47
48/*
49 * sends a 'reschedule' event to another CPU:
50 */
51extern void smp_send_reschedule(int cpu);
52
53
54/*
55 * Prepare machine for booting other CPUs.
56 */
57extern void smp_prepare_cpus(unsigned int max_cpus);
58
59/*
60 * Bring a CPU up
61 */
62extern int __cpu_up(unsigned int cpunum);
63
64/*
65 * Final polishing of CPUs
66 */
67extern void smp_cpus_done(unsigned int max_cpus);
68
69/*
70 * Call a function on all other processors
71 */
72int smp_call_function(void(*func)(void *info), void *info, int wait);
73void smp_call_function_many(const struct cpumask *mask,
74 void (*func)(void *info), void *info, bool wait);
75
76void __smp_call_function_single(int cpuid, struct call_single_data *data,
77 int wait);
78
79int smp_call_function_any(const struct cpumask *mask,
80 void (*func)(void *info), void *info, int wait);
81
82/*
83 * Generic and arch helpers
84 */
85#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
86void generic_smp_call_function_single_interrupt(void);
87void generic_smp_call_function_interrupt(void);
88void ipi_call_lock(void);
89void ipi_call_unlock(void);
90void ipi_call_lock_irq(void);
91void ipi_call_unlock_irq(void);
92#endif
93
94/*
95 * Call a function on all processors
96 */
97int on_each_cpu(void (*func) (void *info), void *info, int wait);
98
99#define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
100#define MSG_ALL 0x8001
101
102#define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
103#define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
104 * when rebooting
105 */
106#define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
107#define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
108
109/*
110 * Mark the boot cpu "online" so that it can call console drivers in
111 * printk() and can access its per-cpu storage.
112 */
113void smp_prepare_boot_cpu(void);
114
115extern unsigned int setup_max_cpus;
116
117#else /* !SMP */
118
119static inline void smp_send_stop(void) { }
120
121/*
122 * These macros fold the SMP functionality into a single CPU system
123 */
124#define raw_smp_processor_id() 0
125static inline int up_smp_call_function(void (*func)(void *), void *info)
126{
127 return 0;
128}
129#define smp_call_function(func, info, wait) \
130 (up_smp_call_function(func, info))
131#define on_each_cpu(func,info,wait) \
132 ({ \
133 local_irq_disable(); \
134 func(info); \
135 local_irq_enable(); \
136 0; \
137 })
138static inline void smp_send_reschedule(int cpu) { }
139#define num_booting_cpus() 1
140#define smp_prepare_boot_cpu() do {} while (0)
141#define smp_call_function_many(mask, func, info, wait) \
142 (up_smp_call_function(func, info))
143static inline void init_call_single_data(void) { }
144
145static inline int
146smp_call_function_any(const struct cpumask *mask, void (*func)(void *info),
147 void *info, int wait)
148{
149 return smp_call_function_single(0, func, info, wait);
150}
151
152#endif /* !SMP */
153
154/*
155 * smp_processor_id(): get the current CPU ID.
156 *
157 * if DEBUG_PREEMPT is enabled then we check whether it is
158 * used in a preemption-safe way. (smp_processor_id() is safe
159 * if it's used in a preemption-off critical section, or in
160 * a thread that is bound to the current CPU.)
161 *
162 * NOTE: raw_smp_processor_id() is for internal use only
163 * (smp_processor_id() is the preferred variant), but in rare
164 * instances it might also be used to turn off false positives
165 * (i.e. smp_processor_id() use that the debugging code reports but
166 * which use for some reason is legal). Don't use this to hack around
167 * the warning message, as your code might not work under PREEMPT.
168 */
169#ifdef CONFIG_DEBUG_PREEMPT
170 extern unsigned int debug_smp_processor_id(void);
171# define smp_processor_id() debug_smp_processor_id()
172#else
173# define smp_processor_id() raw_smp_processor_id()
174#endif
175
176#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
177#define put_cpu() preempt_enable()
178
179/*
180 * Callback to arch code if there's nosmp or maxcpus=0 on the
181 * boot command line:
182 */
183extern void arch_disable_smp_support(void);
184
185void smp_setup_processor_id(void);
186
187#endif /* __LINUX_SMP_H */