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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
10extern void cpu_idle(void);
11
12#ifdef CONFIG_SMP
13
14#include <linux/preempt.h>
15#include <linux/kernel.h>
16#include <linux/compiler.h>
17#include <linux/thread_info.h>
18#include <asm/smp.h>
19
20/*
21 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
22 * (defined in asm header):
23 */
24
25/*
26 * stops all CPUs but the current one:
27 */
28extern void smp_send_stop(void);
29
30/*
31 * sends a 'reschedule' event to another CPU:
32 */
33extern void smp_send_reschedule(int cpu);
34
35
36/*
37 * Prepare machine for booting other CPUs.
38 */
39extern void smp_prepare_cpus(unsigned int max_cpus);
40
41/*
42 * Bring a CPU up
43 */
44extern int __cpu_up(unsigned int cpunum);
45
46/*
47 * Final polishing of CPUs
48 */
49extern void smp_cpus_done(unsigned int max_cpus);
50
51/*
52 * Call a function on all other processors
53 */
54int smp_call_function(void(*func)(void *info), void *info, int retry, int wait);
55
56int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
57 int retry, int wait);
58
59/*
60 * Call a function on all processors
61 */
62int on_each_cpu(void (*func) (void *info), void *info, int retry, int wait);
63
64#define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
65#define MSG_ALL 0x8001
66
67#define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
68#define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
69 * when rebooting
70 */
71#define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
72#define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
73
74/*
75 * Mark the boot cpu "online" so that it can call console drivers in
76 * printk() and can access its per-cpu storage.
77 */
78void smp_prepare_boot_cpu(void);
79
80#else /* !SMP */
81
82/*
83 * These macros fold the SMP functionality into a single CPU system
84 */
85#define raw_smp_processor_id() 0
86#define hard_smp_processor_id() 0
87static inline int up_smp_call_function(void)
88{
89 return 0;
90}
91#define smp_call_function(func,info,retry,wait) (up_smp_call_function())
92#define on_each_cpu(func,info,retry,wait) \
93 ({ \
94 local_irq_disable(); \
95 func(info); \
96 local_irq_enable(); \
97 0; \
98 })
99static inline void smp_send_reschedule(int cpu) { }
100#define num_booting_cpus() 1
101#define smp_prepare_boot_cpu() do {} while (0)
102static inline int smp_call_function_single(int cpuid, void (*func) (void *info),
103 void *info, int retry, int wait)
104{
105 /* Disable interrupts here? */
106 func(info);
107 return 0;
108}
109
110#endif /* !SMP */
111
112/*
113 * smp_processor_id(): get the current CPU ID.
114 *
115 * if DEBUG_PREEMPT is enabled the we check whether it is
116 * used in a preemption-safe way. (smp_processor_id() is safe
117 * if it's used in a preemption-off critical section, or in
118 * a thread that is bound to the current CPU.)
119 *
120 * NOTE: raw_smp_processor_id() is for internal use only
121 * (smp_processor_id() is the preferred variant), but in rare
122 * instances it might also be used to turn off false positives
123 * (i.e. smp_processor_id() use that the debugging code reports but
124 * which use for some reason is legal). Don't use this to hack around
125 * the warning message, as your code might not work under PREEMPT.
126 */
127#ifdef CONFIG_DEBUG_PREEMPT
128 extern unsigned int debug_smp_processor_id(void);
129# define smp_processor_id() debug_smp_processor_id()
130#else
131# define smp_processor_id() raw_smp_processor_id()
132#endif
133
134#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
135#define put_cpu() preempt_enable()
136#define put_cpu_no_resched() preempt_enable_no_resched()
137
138void smp_setup_processor_id(void);
139
140#endif /* __LINUX_SMP_H */