aboutsummaryrefslogtreecommitdiff
path: root/include/linux/smp.h
blob: 48262f86c969dccd11486ef772907845d6cb45cb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
#ifndef __LINUX_SMP_H
#define __LINUX_SMP_H

/*
 *	Generic SMP support
 *		Alan Cox. <alan@redhat.com>
 */

#include <linux/errno.h>
#include <linux/list.h>
#include <linux/cpumask.h>

extern void cpu_idle(void);

struct call_single_data {
	struct list_head list;
	void (*func) (void *info);
	void *info;
	unsigned int flags;
};

#ifdef CONFIG_SMP

#include <linux/preempt.h>
#include <linux/kernel.h>
#include <linux/compiler.h>
#include <linux/thread_info.h>
#include <asm/smp.h>

/*
 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
 * (defined in asm header):
 */ 

/*
 * stops all CPUs but the current one:
 */
extern void smp_send_stop(void);

/*
 * sends a 'reschedule' event to another CPU:
 */
extern void smp_send_reschedule(int cpu);


/*
 * Prepare machine for booting other CPUs.
 */
extern void smp_prepare_cpus(unsigned int max_cpus);

/*
 * Bring a CPU up
 */
extern int __cpu_up(unsigned int cpunum);

/*
 * Final polishing of CPUs
 */
extern void smp_cpus_done(unsigned int max_cpus);

/*
 * Call a function on all other processors
 */
int smp_call_function(void(*func)(void *info), void *info, int wait);
int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info,
				int wait);
int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
				int wait);
void __smp_call_function_single(int cpuid, struct call_single_data *data);

/*
 * Generic and arch helpers
 */
#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
void generic_smp_call_function_single_interrupt(void);
void generic_smp_call_function_interrupt(void);
void init_call_single_data(void);
void ipi_call_lock(void);
void ipi_call_unlock(void);
void ipi_call_lock_irq(void);
void ipi_call_unlock_irq(void);
#else
static inline void init_call_single_data(void)
{
}
#endif

/*
 * Call a function on all processors
 */
int on_each_cpu(void (*func) (void *info), void *info, int wait);

#define MSG_ALL_BUT_SELF	0x8000	/* Assume <32768 CPU's */
#define MSG_ALL			0x8001

#define MSG_INVALIDATE_TLB	0x0001	/* Remote processor TLB invalidate */
#define MSG_STOP_CPU		0x0002	/* Sent to shut down slave CPU's
					 * when rebooting
					 */
#define MSG_RESCHEDULE		0x0003	/* Reschedule request from master CPU*/
#define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */

/*
 * Mark the boot cpu "online" so that it can call console drivers in
 * printk() and can access its per-cpu storage.
 */
void smp_prepare_boot_cpu(void);

extern unsigned int setup_max_cpus;

#else /* !SMP */

/*
 *	These macros fold the SMP functionality into a single CPU system
 */
#define raw_smp_processor_id()			0
static inline int up_smp_call_function(void (*func)(void *), void *info)
{
	return 0;
}
#define smp_call_function(func, info, wait) \
			(up_smp_call_function(func, info))
#define on_each_cpu(func,info,wait)		\
	({					\
		local_irq_disable();		\
		func(info);			\
		local_irq_enable();		\
		0;				\
	})
static inline void smp_send_reschedule(int cpu) { }
#define num_booting_cpus()			1
#define smp_prepare_boot_cpu()			do {} while (0)
#define smp_call_function_single(cpuid, func, info, wait) \
({ \
	WARN_ON(cpuid != 0);	\
	local_irq_disable();	\
	(func)(info);		\
	local_irq_enable();	\
	0;			\
})
#define smp_call_function_mask(mask, func, info, wait) \
			(up_smp_call_function(func, info))
static inline void init_call_single_data(void)
{
}
#endif /* !SMP */

/*
 * smp_processor_id(): get the current CPU ID.
 *
 * if DEBUG_PREEMPT is enabled the we check whether it is
 * used in a preemption-safe way. (smp_processor_id() is safe
 * if it's used in a preemption-off critical section, or in
 * a thread that is bound to the current CPU.)
 *
 * NOTE: raw_smp_processor_id() is for internal use only
 * (smp_processor_id() is the preferred variant), but in rare
 * instances it might also be used to turn off false positives
 * (i.e. smp_processor_id() use that the debugging code reports but
 * which use for some reason is legal). Don't use this to hack around
 * the warning message, as your code might not work under PREEMPT.
 */
#ifdef CONFIG_DEBUG_PREEMPT
  extern unsigned int debug_smp_processor_id(void);
# define smp_processor_id() debug_smp_processor_id()
#else
# define smp_processor_id() raw_smp_processor_id()
#endif

#define get_cpu()		({ preempt_disable(); smp_processor_id(); })
#define put_cpu()		preempt_enable()
#define put_cpu_no_resched()	preempt_enable_no_resched()

void smp_setup_processor_id(void);

#endif /* __LINUX_SMP_H */