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
10 extern void cpu_idle(void);
11
12 #ifdef CONFIG_SMP
13
14 #include <linux/preempt.h>
15 #include <linux/kernel.h>
16 #include <linux/compiler.h>
17 #include <linux/thread_info.h>
18 #include <asm/smp.h>
19
20 /*
21 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
22 * (defined in asm header):
23 */
24
25 /*
26 * stops all CPUs but the current one:
27 */
28 extern void smp_send_stop(void);
29
30 /*
31 * sends a 'reschedule' event to another CPU:
32 */
33 extern void smp_send_reschedule(int cpu);
34
35
36 /*
37 * Prepare machine for booting other CPUs.
38 */
39 extern void smp_prepare_cpus(unsigned int max_cpus);
40
41 /*
42 * Bring a CPU up
43 */
44 extern int __cpu_up(unsigned int cpunum);
45
46 /*
47 * Final polishing of CPUs
48 */
49 extern void smp_cpus_done(unsigned int max_cpus);
50
51 /*
52 * Call a function on all other processors
53 */
54 int smp_call_function(void(*func)(void *info), void *info, int retry, int wait);
55
56 /*
57 * Call a function on all processors
58 */
59 int on_each_cpu(void (*func) (void *info), void *info, int retry, int wait);
60
61 #define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
62 #define MSG_ALL 0x8001
63
64 #define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
65 #define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
66 * when rebooting
67 */
68 #define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
69 #define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
70
71 /*
72 * Mark the boot cpu "online" so that it can call console drivers in
73 * printk() and can access its per-cpu storage.
74 */
75 void smp_prepare_boot_cpu(void);
76
77 #else /* !SMP */
78
79 /*
80 * These macros fold the SMP functionality into a single CPU system
81 */
82 #define raw_smp_processor_id() 0
83 #define hard_smp_processor_id() 0
up_smp_call_function(void)84 static inline int up_smp_call_function(void)
85 {
86 return 0;
87 }
88 #define smp_call_function(func,info,retry,wait) (up_smp_call_function())
89 #define on_each_cpu(func,info,retry,wait) \
90 ({ \
91 local_irq_disable(); \
92 func(info); \
93 local_irq_enable(); \
94 0; \
95 })
smp_send_reschedule(int cpu)96 static inline void smp_send_reschedule(int cpu) { }
97 #define num_booting_cpus() 1
98 #define smp_prepare_boot_cpu() do {} while (0)
99
100 #endif /* !SMP */
101
102 /*
103 * smp_processor_id(): get the current CPU ID.
104 *
105 * if DEBUG_PREEMPT is enabled the we check whether it is
106 * used in a preemption-safe way. (smp_processor_id() is safe
107 * if it's used in a preemption-off critical section, or in
108 * a thread that is bound to the current CPU.)
109 *
110 * NOTE: raw_smp_processor_id() is for internal use only
111 * (smp_processor_id() is the preferred variant), but in rare
112 * instances it might also be used to turn off false positives
113 * (i.e. smp_processor_id() use that the debugging code reports but
114 * which use for some reason is legal). Don't use this to hack around
115 * the warning message, as your code might not work under PREEMPT.
116 */
117 #ifdef CONFIG_DEBUG_PREEMPT
118 extern unsigned int debug_smp_processor_id(void);
119 # define smp_processor_id() debug_smp_processor_id()
120 #else
121 # define smp_processor_id() raw_smp_processor_id()
122 #endif
123
124 #define get_cpu() ({ preempt_disable(); smp_processor_id(); })
125 #define put_cpu() preempt_enable()
126 #define put_cpu_no_resched() preempt_enable_no_resched()
127
128 void smp_setup_processor_id(void);
129
130 #endif /* __LINUX_SMP_H */
131