summaryrefslogtreecommitdiffstats
path: root/include/linux/smp.h
blob: 7ad824d510a2138bca6b7e3d1ec8aae4c0ac014a (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
177
178
179
180
181
#ifndef __LINUX_SMP_H
#define __LINUX_SMP_H

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

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

extern void cpu_idle(void);

typedef void (*smp_call_func_t)(void *info);
struct call_single_data {
	struct list_head list;
	smp_call_func_t func;
	void *info;
	u16 flags;
	u16 priv;
};

/* total number of cpus in this system (may exceed NR_CPUS) */
extern unsigned int total_cpus;

int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
			     int wait);

#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(smp_call_func_t func, void *info, int wait);
void smp_call_function_many(const struct cpumask *mask,
			    smp_call_func_t func, void *info, bool wait);

void __smp_call_function_single(int cpuid, struct call_single_data *data,
				int wait);

int smp_call_function_any(const struct cpumask *mask,
			  smp_call_func_t func, void *info, int wait);

/*
 * 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 ipi_call_lock(void);
void ipi_call_unlock(void);
void ipi_call_lock_irq(void);
void ipi_call_unlock_irq(void);
#endif

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

/*
 * 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;
extern void __init setup_nr_cpu_ids(void);
extern void __init smp_init(void);

#else /* !SMP */

static inline void smp_send_stop(void) { }

/*
 *	These macros fold the SMP functionality into a single CPU system
 */
#define raw_smp_processor_id()			0
static inline int up_smp_call_function(smp_call_func_t func, 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_many(mask, func, info, wait) \
			(up_smp_call_function(func, info))
static inline void init_call_single_data(void) { }

static inline int
smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
		      void *info, int wait)
{
	return smp_call_function_single(0, func, info, wait);
}

#endif /* !SMP */

/*
 * smp_processor_id(): get the current CPU ID.
 *
 * if DEBUG_PREEMPT is enabled then 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()

/*
 * Callback to arch code if there's nosmp or maxcpus=0 on the
 * boot command line:
 */
extern void arch_disable_smp_support(void);

void smp_setup_processor_id(void);

#endif /* __LINUX_SMP_H */
OpenPOWER on IntegriCloud