1 /* SPDX-License-Identifier: GPL-2.0 */
7 * Alan Cox. <alan@redhat.com>
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/list.h>
13 #include <linux/cpumask.h>
14 #include <linux/init.h>
15 #include <linux/llist.h>
17 typedef void (*smp_call_func_t)(void *info);
18 struct __call_single_data {
19 struct llist_node llist;
25 /* Use __aligned() to avoid to use 2 cache lines for 1 csd */
26 typedef struct __call_single_data call_single_data_t
27 __aligned(sizeof(struct __call_single_data));
29 /* total number of cpus in this system (may exceed NR_CPUS) */
30 extern unsigned int total_cpus;
32 int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
36 * Call a function on all processors
38 void on_each_cpu(smp_call_func_t func, void *info, int wait);
41 * Call a function on processors specified by mask, which might include
44 void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
45 void *info, bool wait);
48 * Call a function on each processor for which the supplied function
49 * cond_func returns a positive value. This may include the local
52 void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
53 smp_call_func_t func, void *info, bool wait,
56 void on_each_cpu_cond_mask(bool (*cond_func)(int cpu, void *info),
57 smp_call_func_t func, void *info, bool wait,
58 gfp_t gfp_flags, const struct cpumask *mask);
60 int smp_call_function_single_async(int cpu, call_single_data_t *csd);
64 #include <linux/preempt.h>
65 #include <linux/kernel.h>
66 #include <linux/compiler.h>
67 #include <linux/thread_info.h>
71 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
72 * (defined in asm header):
76 * stops all CPUs but the current one:
78 extern void smp_send_stop(void);
81 * sends a 'reschedule' event to another CPU:
83 extern void smp_send_reschedule(int cpu);
87 * Prepare machine for booting other CPUs.
89 extern void smp_prepare_cpus(unsigned int max_cpus);
94 extern int __cpu_up(unsigned int cpunum, struct task_struct *tidle);
97 * Final polishing of CPUs
99 extern void smp_cpus_done(unsigned int max_cpus);
102 * Call a function on all other processors
104 void smp_call_function(smp_call_func_t func, void *info, int wait);
105 void smp_call_function_many(const struct cpumask *mask,
106 smp_call_func_t func, void *info, bool wait);
108 int smp_call_function_any(const struct cpumask *mask,
109 smp_call_func_t func, void *info, int wait);
111 void kick_all_cpus_sync(void);
112 void wake_up_all_idle_cpus(void);
115 * Generic and arch helpers
117 void __init call_function_init(void);
118 void generic_smp_call_function_single_interrupt(void);
119 #define generic_smp_call_function_interrupt \
120 generic_smp_call_function_single_interrupt
123 * Mark the boot cpu "online" so that it can call console drivers in
124 * printk() and can access its per-cpu storage.
126 void smp_prepare_boot_cpu(void);
128 extern unsigned int setup_max_cpus;
129 extern void __init setup_nr_cpu_ids(void);
130 extern void __init smp_init(void);
132 extern int __boot_cpu_id;
134 static inline int get_boot_cpu_id(void)
136 return __boot_cpu_id;
141 static inline void smp_send_stop(void) { }
144 * These macros fold the SMP functionality into a single CPU system
146 #define raw_smp_processor_id() 0
147 static inline void up_smp_call_function(smp_call_func_t func, void *info)
150 #define smp_call_function(func, info, wait) \
151 (up_smp_call_function(func, info))
153 static inline void smp_send_reschedule(int cpu) { }
154 #define smp_prepare_boot_cpu() do {} while (0)
155 #define smp_call_function_many(mask, func, info, wait) \
156 (up_smp_call_function(func, info))
157 static inline void call_function_init(void) { }
160 smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
161 void *info, int wait)
163 return smp_call_function_single(0, func, info, wait);
166 static inline void kick_all_cpus_sync(void) { }
167 static inline void wake_up_all_idle_cpus(void) { }
169 #ifdef CONFIG_UP_LATE_INIT
170 extern void __init up_late_init(void);
171 static inline void smp_init(void) { up_late_init(); }
173 static inline void smp_init(void) { }
176 static inline int get_boot_cpu_id(void)
184 * smp_processor_id(): get the current CPU ID.
186 * if DEBUG_PREEMPT is enabled then we check whether it is
187 * used in a preemption-safe way. (smp_processor_id() is safe
188 * if it's used in a preemption-off critical section, or in
189 * a thread that is bound to the current CPU.)
191 * NOTE: raw_smp_processor_id() is for internal use only
192 * (smp_processor_id() is the preferred variant), but in rare
193 * instances it might also be used to turn off false positives
194 * (i.e. smp_processor_id() use that the debugging code reports but
195 * which use for some reason is legal). Don't use this to hack around
196 * the warning message, as your code might not work under PREEMPT.
198 #ifdef CONFIG_DEBUG_PREEMPT
199 extern unsigned int debug_smp_processor_id(void);
200 # define smp_processor_id() debug_smp_processor_id()
202 # define smp_processor_id() raw_smp_processor_id()
205 #define get_cpu() ({ preempt_disable(); smp_processor_id(); })
206 #define put_cpu() preempt_enable()
209 * Callback to arch code if there's nosmp or maxcpus=0 on the
212 extern void arch_disable_smp_support(void);
214 extern void arch_enable_nonboot_cpus_begin(void);
215 extern void arch_enable_nonboot_cpus_end(void);
217 void smp_setup_processor_id(void);
219 int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par,
222 /* SMP core functions */
223 int smpcfd_prepare_cpu(unsigned int cpu);
224 int smpcfd_dead_cpu(unsigned int cpu);
225 int smpcfd_dying_cpu(unsigned int cpu);
227 #endif /* __LINUX_SMP_H */