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Linux kernel mirror (for testing)
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linux
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/list.h>
11#include <linux/cpumask.h>
12
13extern void cpu_idle(void);
14
15struct call_single_data {
16 struct list_head list;
17 void (*func) (void *info);
18 void *info;
19 unsigned int flags;
20};
21
22#ifdef CONFIG_SMP
23
24#include <linux/preempt.h>
25#include <linux/kernel.h>
26#include <linux/compiler.h>
27#include <linux/thread_info.h>
28#include <asm/smp.h>
29
30/*
31 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
32 * (defined in asm header):
33 */
34
35/*
36 * stops all CPUs but the current one:
37 */
38extern void smp_send_stop(void);
39
40/*
41 * sends a 'reschedule' event to another CPU:
42 */
43extern void smp_send_reschedule(int cpu);
44
45
46/*
47 * Prepare machine for booting other CPUs.
48 */
49extern void smp_prepare_cpus(unsigned int max_cpus);
50
51/*
52 * Bring a CPU up
53 */
54extern int __cpu_up(unsigned int cpunum);
55
56/*
57 * Final polishing of CPUs
58 */
59extern void smp_cpus_done(unsigned int max_cpus);
60
61/*
62 * Call a function on all other processors
63 */
64int smp_call_function(void(*func)(void *info), void *info, int wait);
65int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
66 int wait);
67int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
68 int wait);
69void __smp_call_function_single(int cpuid, struct call_single_data *data);
70
71/*
72 * Generic and arch helpers
73 */
74#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
75void generic_smp_call_function_single_interrupt(void);
76void generic_smp_call_function_interrupt(void);
77void init_call_single_data(void);
78void ipi_call_lock(void);
79void ipi_call_unlock(void);
80void ipi_call_lock_irq(void);
81void ipi_call_unlock_irq(void);
82#else
83static inline void init_call_single_data(void)
84{
85}
86#endif
87
88/*
89 * Call a function on all processors
90 */
91int on_each_cpu(void (*func) (void *info), void *info, int wait);
92
93#define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
94#define MSG_ALL 0x8001
95
96#define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
97#define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
98 * when rebooting
99 */
100#define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
101#define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
102
103/*
104 * Mark the boot cpu "online" so that it can call console drivers in
105 * printk() and can access its per-cpu storage.
106 */
107void smp_prepare_boot_cpu(void);
108
109extern unsigned int setup_max_cpus;
110
111#else /* !SMP */
112
113/*
114 * These macros fold the SMP functionality into a single CPU system
115 */
116#define raw_smp_processor_id() 0
117static inline int up_smp_call_function(void (*func)(void *), void *info)
118{
119 return 0;
120}
121#define smp_call_function(func, info, wait) \
122 (up_smp_call_function(func, info))
123#define on_each_cpu(func,info,wait) \
124 ({ \
125 local_irq_disable(); \
126 func(info); \
127 local_irq_enable(); \
128 0; \
129 })
130static inline void smp_send_reschedule(int cpu) { }
131#define num_booting_cpus() 1
132#define smp_prepare_boot_cpu() do {} while (0)
133#define smp_call_function_single(cpuid, func, info, wait) \
134({ \
135 WARN_ON(cpuid != 0); \
136 local_irq_disable(); \
137 (func)(info); \
138 local_irq_enable(); \
139 0; \
140})
141#define smp_call_function_mask(mask, func, info, wait) \
142 (up_smp_call_function(func, info))
143static inline void init_call_single_data(void)
144{
145}
146#endif /* !SMP */
147
148/*
149 * smp_processor_id(): get the current CPU ID.
150 *
151 * if DEBUG_PREEMPT is enabled the we check whether it is
152 * used in a preemption-safe way. (smp_processor_id() is safe
153 * if it's used in a preemption-off critical section, or in
154 * a thread that is bound to the current CPU.)
155 *
156 * NOTE: raw_smp_processor_id() is for internal use only
157 * (smp_processor_id() is the preferred variant), but in rare
158 * instances it might also be used to turn off false positives
159 * (i.e. smp_processor_id() use that the debugging code reports but
160 * which use for some reason is legal). Don't use this to hack around
161 * the warning message, as your code might not work under PREEMPT.
162 */
163#ifdef CONFIG_DEBUG_PREEMPT
164 extern unsigned int debug_smp_processor_id(void);
165# define smp_processor_id() debug_smp_processor_id()
166#else
167# define smp_processor_id() raw_smp_processor_id()
168#endif
169
170#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
171#define put_cpu() preempt_enable()
172#define put_cpu_no_resched() preempt_enable_no_resched()
173
174void smp_setup_processor_id(void);
175
176#endif /* __LINUX_SMP_H */