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
16 typedef void (*smp_call_func_t)(void *info);
17 struct 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) */
25 extern unsigned int total_cpus;
26
27 int 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 */
33 int 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 */
39 void 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 */
47 void 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
51 int 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 */
69 extern void smp_send_stop(void);
70
71 /*
72 * sends a 'reschedule' event to another CPU:
73 */
74 extern void smp_send_reschedule(int cpu);
75
76
77 /*
78 * Prepare machine for booting other CPUs.
79 */
80 extern void smp_prepare_cpus(unsigned int max_cpus);
81
82 /*
83 * Bring a CPU up
84 */
85 extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
86
87 /*
88 * Final polishing of CPUs
89 */
90 extern void smp_cpus_done(unsigned int max_cpus);
91
92 /*
93 * Call a function on all other processors
94 */
95 int smp_call_function(smp_call_func_t func, void *info, int wait);
96 void smp_call_function_many(const struct cpumask *mask,
97 smp_call_func_t func, void *info, bool wait);
98
99 int smp_call_function_any(const struct cpumask *mask,
100 smp_call_func_t func, void *info, int wait);
101
102 void kick_all_cpus_sync(void);
103 void wake_up_all_idle_cpus(void);
104
105 /*
106 * Generic and arch helpers
107 */
108 void __init call_function_init(void);
109 void 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 */
117 void smp_prepare_boot_cpu(void);
118
119 extern unsigned int setup_max_cpus;
120 extern void __init setup_nr_cpu_ids(void);
121 extern void __init smp_init(void);
122
123 #else /* !SMP */
124
smp_send_stop(void)125 static 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
up_smp_call_function(smp_call_func_t func,void * info)131 static 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
smp_send_reschedule(int cpu)138 static 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))
call_function_init(void)142 static inline void call_function_init(void) { }
143
144 static inline int
smp_call_function_any(const struct cpumask * mask,smp_call_func_t func,void * info,int wait)145 smp_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
kick_all_cpus_sync(void)151 static inline void kick_all_cpus_sync(void) { }
wake_up_all_idle_cpus(void)152 static inline void wake_up_all_idle_cpus(void) { }
153
154 #ifdef CONFIG_UP_LATE_INIT
155 extern void __init up_late_init(void);
smp_init(void)156 static inline void smp_init(void) { up_late_init(); }
157 #else
smp_init(void)158 static 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 */
192 extern void arch_disable_smp_support(void);
193
194 extern void arch_enable_nonboot_cpus_begin(void);
195 extern void arch_enable_nonboot_cpus_end(void);
196
197 void smp_setup_processor_id(void);
198
199 #endif /* __LINUX_SMP_H */
200