Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
14extern void cpu_idle(void);
15
16typedef void (*smp_call_func_t)(void *info);
17struct call_single_data {
18 struct list_head list;
19 smp_call_func_t func;
20 void *info;
21 u16 flags;
22 u16 priv;
23};
24
25/* total number of cpus in this system (may exceed NR_CPUS) */
26extern unsigned int total_cpus;
27
28int smp_call_function_single(int cpuid, smp_call_func_t func, void *info,
29 int wait);
30
31#ifdef CONFIG_SMP
32
33#include <linux/preempt.h>
34#include <linux/kernel.h>
35#include <linux/compiler.h>
36#include <linux/thread_info.h>
37#include <asm/smp.h>
38
39/*
40 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
41 * (defined in asm header):
42 */
43
44/*
45 * stops all CPUs but the current one:
46 */
47extern void smp_send_stop(void);
48
49/*
50 * sends a 'reschedule' event to another CPU:
51 */
52extern void smp_send_reschedule(int cpu);
53
54
55/*
56 * Prepare machine for booting other CPUs.
57 */
58extern void smp_prepare_cpus(unsigned int max_cpus);
59
60/*
61 * Bring a CPU up
62 */
63extern int __cpu_up(unsigned int cpunum);
64
65/*
66 * Final polishing of CPUs
67 */
68extern void smp_cpus_done(unsigned int max_cpus);
69
70/*
71 * Call a function on all other processors
72 */
73int smp_call_function(smp_call_func_t func, void *info, int wait);
74void smp_call_function_many(const struct cpumask *mask,
75 smp_call_func_t func, void *info, bool wait);
76
77void __smp_call_function_single(int cpuid, struct call_single_data *data,
78 int wait);
79
80int smp_call_function_any(const struct cpumask *mask,
81 smp_call_func_t func, void *info, int wait);
82
83/*
84 * Generic and arch helpers
85 */
86#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
87void generic_smp_call_function_single_interrupt(void);
88void generic_smp_call_function_interrupt(void);
89void ipi_call_lock(void);
90void ipi_call_unlock(void);
91void ipi_call_lock_irq(void);
92void ipi_call_unlock_irq(void);
93#endif
94
95/*
96 * Call a function on all processors
97 */
98int on_each_cpu(smp_call_func_t func, void *info, int wait);
99
100#define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
101#define MSG_ALL 0x8001
102
103#define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
104#define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
105 * when rebooting
106 */
107#define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
108#define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
109
110/*
111 * Mark the boot cpu "online" so that it can call console drivers in
112 * printk() and can access its per-cpu storage.
113 */
114void smp_prepare_boot_cpu(void);
115
116extern unsigned int setup_max_cpus;
117
118#else /* !SMP */
119
120static inline void smp_send_stop(void) { }
121
122/*
123 * These macros fold the SMP functionality into a single CPU system
124 */
125#define raw_smp_processor_id() 0
126static inline int up_smp_call_function(smp_call_func_t func, void *info)
127{
128 return 0;
129}
130#define smp_call_function(func, info, wait) \
131 (up_smp_call_function(func, info))
132#define on_each_cpu(func,info,wait) \
133 ({ \
134 local_irq_disable(); \
135 func(info); \
136 local_irq_enable(); \
137 0; \
138 })
139static inline void smp_send_reschedule(int cpu) { }
140#define num_booting_cpus() 1
141#define smp_prepare_boot_cpu() do {} while (0)
142#define smp_call_function_many(mask, func, info, wait) \
143 (up_smp_call_function(func, info))
144static inline void init_call_single_data(void) { }
145
146static inline int
147smp_call_function_any(const struct cpumask *mask, smp_call_func_t func,
148 void *info, int wait)
149{
150 return smp_call_function_single(0, func, info, wait);
151}
152
153#endif /* !SMP */
154
155/*
156 * smp_processor_id(): get the current CPU ID.
157 *
158 * if DEBUG_PREEMPT is enabled then we check whether it is
159 * used in a preemption-safe way. (smp_processor_id() is safe
160 * if it's used in a preemption-off critical section, or in
161 * a thread that is bound to the current CPU.)
162 *
163 * NOTE: raw_smp_processor_id() is for internal use only
164 * (smp_processor_id() is the preferred variant), but in rare
165 * instances it might also be used to turn off false positives
166 * (i.e. smp_processor_id() use that the debugging code reports but
167 * which use for some reason is legal). Don't use this to hack around
168 * the warning message, as your code might not work under PREEMPT.
169 */
170#ifdef CONFIG_DEBUG_PREEMPT
171 extern unsigned int debug_smp_processor_id(void);
172# define smp_processor_id() debug_smp_processor_id()
173#else
174# define smp_processor_id() raw_smp_processor_id()
175#endif
176
177#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
178#define put_cpu() preempt_enable()
179
180/*
181 * Callback to arch code if there's nosmp or maxcpus=0 on the
182 * boot command line:
183 */
184extern void arch_disable_smp_support(void);
185
186void smp_setup_processor_id(void);
187
188#endif /* __LINUX_SMP_H */