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