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/errno.h>
10#include <linux/types.h>
11#include <linux/list.h>
12#include <linux/cpumask.h>
13#include <linux/init.h>
14#include <linux/llist.h>
15
16typedef void (*smp_call_func_t)(void *info);
17struct call_single_data {
18	struct llist_node llist;
19	smp_call_func_t func;
20	void *info;
21	unsigned int flags;
22};
23
24/* total number of cpus in this system (may exceed NR_CPUS) */
25extern unsigned int total_cpus;
26
27int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
28			     int wait);
29
30/*
31 * Call a function on all processors
32 */
33int on_each_cpu(smp_call_func_t func, void *info, int wait);
34
35/*
36 * Call a function on processors specified by mask, which might include
37 * the local one.
38 */
39void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
40		void *info, bool wait);
41
42/*
43 * Call a function on each processor for which the supplied function
44 * cond_func returns a positive value. This may include the local
45 * processor.
46 */
47void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
48		smp_call_func_t func, void *info, bool wait,
49		gfp_t gfp_flags);
50
51int smp_call_function_single_async(int cpu, struct call_single_data *csd);
52
53#ifdef CONFIG_SMP
54
55#include <linux/preempt.h>
56#include <linux/kernel.h>
57#include <linux/compiler.h>
58#include <linux/thread_info.h>
59#include <asm/smp.h>
60
61/*
62 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
63 * (defined in asm header):
64 */
65
66/*
67 * stops all CPUs but the current one:
68 */
69extern void smp_send_stop(void);
70
71/*
72 * sends a 'reschedule' event to another CPU:
73 */
74extern void smp_send_reschedule(int cpu);
75
76
77/*
78 * Prepare machine for booting other CPUs.
79 */
80extern void smp_prepare_cpus(unsigned int max_cpus);
81
82/*
83 * Bring a CPU up
84 */
85extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
86
87/*
88 * Final polishing of CPUs
89 */
90extern void smp_cpus_done(unsigned int max_cpus);
91
92/*
93 * Call a function on all other processors
94 */
95int smp_call_function(smp_call_func_t func, void *info, int wait);
96void smp_call_function_many(const struct cpumask *mask,
97			    smp_call_func_t func, void *info, bool wait);
98
99int smp_call_function_any(const struct cpumask *mask,
100			  smp_call_func_t func, void *info, int wait);
101
102void kick_all_cpus_sync(void);
103void wake_up_all_idle_cpus(void);
104
105/*
106 * Generic and arch helpers
107 */
108void __init call_function_init(void);
109void generic_smp_call_function_single_interrupt(void);
110#define generic_smp_call_function_interrupt \
111	generic_smp_call_function_single_interrupt
112
113/*
114 * Mark the boot cpu "online" so that it can call console drivers in
115 * printk() and can access its per-cpu storage.
116 */
117void smp_prepare_boot_cpu(void);
118
119extern unsigned int setup_max_cpus;
120extern void __init setup_nr_cpu_ids(void);
121extern void __init smp_init(void);
122
123#else /* !SMP */
124
125static inline void smp_send_stop(void) { }
126
127/*
128 *	These macros fold the SMP functionality into a single CPU system
129 */
130#define raw_smp_processor_id()			0
131static inline int up_smp_call_function(smp_call_func_t func, void *info)
132{
133	return 0;
134}
135#define smp_call_function(func, info, wait) \
136			(up_smp_call_function(func, info))
137
138static inline void smp_send_reschedule(int cpu) { }
139#define smp_prepare_boot_cpu()			do {} while (0)
140#define smp_call_function_many(mask, func, info, wait) \
141			(up_smp_call_function(func, info))
142static inline void call_function_init(void) { }
143
144static inline int
145smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
146		      void *info, int wait)
147{
148	return smp_call_function_single(0, func, info, wait);
149}
150
151static inline void kick_all_cpus_sync(void) {  }
152static inline void wake_up_all_idle_cpus(void) {  }
153
154#ifdef CONFIG_UP_LATE_INIT
155extern void __init up_late_init(void);
156static inline void smp_init(void) { up_late_init(); }
157#else
158static inline void smp_init(void) { }
159#endif
160
161#endif /* !SMP */
162
163/*
164 * smp_processor_id(): get the current CPU ID.
165 *
166 * if DEBUG_PREEMPT is enabled then we check whether it is
167 * used in a preemption-safe way. (smp_processor_id() is safe
168 * if it's used in a preemption-off critical section, or in
169 * a thread that is bound to the current CPU.)
170 *
171 * NOTE: raw_smp_processor_id() is for internal use only
172 * (smp_processor_id() is the preferred variant), but in rare
173 * instances it might also be used to turn off false positives
174 * (i.e. smp_processor_id() use that the debugging code reports but
175 * which use for some reason is legal). Don't use this to hack around
176 * the warning message, as your code might not work under PREEMPT.
177 */
178#ifdef CONFIG_DEBUG_PREEMPT
179  extern unsigned int debug_smp_processor_id(void);
180# define smp_processor_id() debug_smp_processor_id()
181#else
182# define smp_processor_id() raw_smp_processor_id()
183#endif
184
185#define get_cpu()		({ preempt_disable(); smp_processor_id(); })
186#define put_cpu()		preempt_enable()
187
188/*
189 * Callback to arch code if there's nosmp or maxcpus=0 on the
190 * boot command line:
191 */
192extern void arch_disable_smp_support(void);
193
194extern void arch_enable_nonboot_cpus_begin(void);
195extern void arch_enable_nonboot_cpus_end(void);
196
197void smp_setup_processor_id(void);
198
199#endif /* __LINUX_SMP_H */
200