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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 */
55extern int smp_call_function (void (*func) (void *info), void *info,
56 int retry, int wait);
57
58/*
59 * Call a function on all processors
60 */
61static inline int on_each_cpu(void (*func) (void *info), void *info,
62 int retry, int wait)
63{
64 int ret = 0;
65
66 preempt_disable();
67 ret = smp_call_function(func, info, retry, wait);
68 func(info);
69 preempt_enable();
70 return ret;
71}
72
73#define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
74#define MSG_ALL 0x8001
75
76#define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
77#define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
78 * when rebooting
79 */
80#define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
81#define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
82
83/*
84 * Mark the boot cpu "online" so that it can call console drivers in
85 * printk() and can access its per-cpu storage.
86 */
87void smp_prepare_boot_cpu(void);
88
89#else /* !SMP */
90
91/*
92 * These macros fold the SMP functionality into a single CPU system
93 */
94#define raw_smp_processor_id() 0
95#define hard_smp_processor_id() 0
96#define smp_call_function(func,info,retry,wait) ({ 0; })
97#define on_each_cpu(func,info,retry,wait) ({ func(info); 0; })
98static inline void smp_send_reschedule(int cpu) { }
99#define num_booting_cpus() 1
100#define smp_prepare_boot_cpu() do {} while (0)
101
102#endif /* !SMP */
103
104/*
105 * smp_processor_id(): get the current CPU ID.
106 *
107 * if DEBUG_PREEMPT is enabled the we check whether it is
108 * used in a preemption-safe way. (smp_processor_id() is safe
109 * if it's used in a preemption-off critical section, or in
110 * a thread that is bound to the current CPU.)
111 *
112 * NOTE: raw_smp_processor_id() is for internal use only
113 * (smp_processor_id() is the preferred variant), but in rare
114 * instances it might also be used to turn off false positives
115 * (i.e. smp_processor_id() use that the debugging code reports but
116 * which use for some reason is legal). Don't use this to hack around
117 * the warning message, as your code might not work under PREEMPT.
118 */
119#ifdef CONFIG_DEBUG_PREEMPT
120 extern unsigned int debug_smp_processor_id(void);
121# define smp_processor_id() debug_smp_processor_id()
122#else
123# define smp_processor_id() raw_smp_processor_id()
124#endif
125
126#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
127#define put_cpu() preempt_enable()
128#define put_cpu_no_resched() preempt_enable_no_resched()
129
130#endif /* __LINUX_SMP_H */