[mirror_ubuntu-bionic-kernel.git] / include / linux / smp.h

#ifndef __LINUX_SMP_H
#define __LINUX_SMP_H

/*
 *	Generic SMP support
 *		Alan Cox. <alan@redhat.com>
 */

#include <linux/config.h>

extern void cpu_idle(void);

#ifdef CONFIG_SMP

#include <linux/preempt.h>
#include <linux/kernel.h>
#include <linux/compiler.h>
#include <linux/thread_info.h>
#include <asm/smp.h>
#include <asm/bug.h>

/*
 * main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
 * (defined in asm header):
 */ 

/*
 * stops all CPUs but the current one:
 */
extern void smp_send_stop(void);

/*
 * sends a 'reschedule' event to another CPU:
 */
extern void smp_send_reschedule(int cpu);


/*
 * Prepare machine for booting other CPUs.
 */
extern void smp_prepare_cpus(unsigned int max_cpus);

/*
 * Bring a CPU up
 */
extern int __cpu_up(unsigned int cpunum);

/*
 * Final polishing of CPUs
 */
extern void smp_cpus_done(unsigned int max_cpus);

/*
 * Call a function on all other processors
 */
extern int smp_call_function (void (*func) (void *info), void *info,
			      int retry, int wait);

/*
 * Call a function on all processors
 */
static inline int on_each_cpu(void (*func) (void *info), void *info,
			      int retry, int wait)
{
	int ret = 0;

	preempt_disable();
	ret = smp_call_function(func, info, retry, wait);
	func(info);
	preempt_enable();
	return ret;
}

#define MSG_ALL_BUT_SELF	0x8000	/* Assume <32768 CPU's */
#define MSG_ALL			0x8001

#define MSG_INVALIDATE_TLB	0x0001	/* Remote processor TLB invalidate */
#define MSG_STOP_CPU		0x0002	/* Sent to shut down slave CPU's
					 * when rebooting
					 */
#define MSG_RESCHEDULE		0x0003	/* Reschedule request from master CPU*/
#define MSG_CALL_FUNCTION       0x0004  /* Call function on all other CPUs */

/*
 * Mark the boot cpu "online" so that it can call console drivers in
 * printk() and can access its per-cpu storage.
 */
void smp_prepare_boot_cpu(void);

#else /* !SMP */

/*
 *	These macros fold the SMP functionality into a single CPU system
 */
#define raw_smp_processor_id()			0
#define hard_smp_processor_id()			0
#define num_booting_cpus()			1

static inline int smp_call_function(void (*func) (void *), void *info,
				    int retry, int wait)
{
	return 0;
}

static inline int on_each_cpu(void (*func) (void *), void *info,
			      int retry, int wait)
{
	func(info);
	return 0;
}

static inline void smp_send_reschedule(int cpu) { }
static inline void smp_prepare_boot_cpu(void) { }

#endif /* !SMP */

/*
 * smp_processor_id(): get the current CPU ID.
 *
 * if DEBUG_PREEMPT is enabled the we check whether it is
 * used in a preemption-safe way. (smp_processor_id() is safe
 * if it's used in a preemption-off critical section, or in
 * a thread that is bound to the current CPU.)
 *
 * NOTE: raw_smp_processor_id() is for internal use only
 * (smp_processor_id() is the preferred variant), but in rare
 * instances it might also be used to turn off false positives
 * (i.e. smp_processor_id() use that the debugging code reports but
 * which use for some reason is legal). Don't use this to hack around
 * the warning message, as your code might not work under PREEMPT.
 */
#ifdef CONFIG_DEBUG_PREEMPT
  extern unsigned int debug_smp_processor_id(void);
# define smp_processor_id() debug_smp_processor_id()
#else
# define smp_processor_id() raw_smp_processor_id()
#endif

#define get_cpu()		({ preempt_disable(); smp_processor_id(); })
#define put_cpu()		preempt_enable()
#define put_cpu_no_resched()	preempt_enable_no_resched()

#endif /* __LINUX_SMP_H */
Commit	Line	Data
1da177e4 LT	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/config.h>
	10
	11	extern void cpu_idle(void);
	12
	13	#ifdef CONFIG_SMP
	14
	15	#include <linux/preempt.h>
	16	#include <linux/kernel.h>
	17	#include <linux/compiler.h>
	18	#include <linux/thread_info.h>
	19	#include <asm/smp.h>
	20	#include <asm/bug.h>
	21
	22	/*
	23	* main cross-CPU interfaces, handles INIT, TLB flush, STOP, etc.
	24	* (defined in asm header):
	25	*/
	26
	27	/*
	28	* stops all CPUs but the current one:
	29	*/
	30	extern void smp_send_stop(void);
	31
	32	/*
	33	* sends a 'reschedule' event to another CPU:
	34	*/
	35	extern void smp_send_reschedule(int cpu);
	36
	37
	38	/*
	39	* Prepare machine for booting other CPUs.
	40	*/
	41	extern void smp_prepare_cpus(unsigned int max_cpus);
	42
	43	/*
	44	* Bring a CPU up
	45	*/
	46	extern int __cpu_up(unsigned int cpunum);
	47
	48	/*
	49	* Final polishing of CPUs
	50	*/
	51	extern void smp_cpus_done(unsigned int max_cpus);
	52
	53	/*
	54	* Call a function on all other processors
	55	*/
	56	extern int smp_call_function (void (func) (void info), void *info,
	57	int retry, int wait);
	58
	59	/*
	60	* Call a function on all processors
	61	*/
	62	static inline int on_each_cpu(void (func) (void info), void *info,
	63	int retry, int wait)
	64	{
65	int ret = 0;
66
67	preempt_disable();
68	ret = smp_call_function(func, info, retry, wait);
69	func(info);
70	preempt_enable();
71	return ret;
72	}
73
74	#define MSG_ALL_BUT_SELF 0x8000 /* Assume <32768 CPU's */
75	#define MSG_ALL 0x8001
76
77	#define MSG_INVALIDATE_TLB 0x0001 /* Remote processor TLB invalidate */
78	#define MSG_STOP_CPU 0x0002 /* Sent to shut down slave CPU's
79	* when rebooting
80	*/
81	#define MSG_RESCHEDULE 0x0003 /* Reschedule request from master CPU*/
82	#define MSG_CALL_FUNCTION 0x0004 /* Call function on all other CPUs */
83
84	/*
85	* Mark the boot cpu "online" so that it can call console drivers in
86	* printk() and can access its per-cpu storage.
87	*/
88	void smp_prepare_boot_cpu(void);
89
90	#else /* !SMP */
91
92	/*
93	* These macros fold the SMP functionality into a single CPU system
94	*/
39c715b7	95	#define raw_smp_processor_id() 0
1da177e4	96	#define hard_smp_processor_id() 0
1da177e4	97	#define num_booting_cpus() 1
79a88102 RH	98
	99	static inline int smp_call_function(void (func) (void ), void *info,
	100	int retry, int wait)
	101	{
	102	return 0;
	103	}
	104
	105	static inline int on_each_cpu(void (func) (void ), void *info,
	106	int retry, int wait)
	107	{
	108	func(info);
	109	return 0;
	110	}
	111
	112	static inline void smp_send_reschedule(int cpu) { }
	113	static inline void smp_prepare_boot_cpu(void) { }
1da177e4 LT	114
	115	#endif /* !SMP */
	116
	117	/*
39c715b7	118	* smp_processor_id(): get the current CPU ID.
1da177e4	119	*
39c715b7 IM	120	* if DEBUG_PREEMPT is enabled the we check whether it is
	121	* used in a preemption-safe way. (smp_processor_id() is safe
	122	* if it's used in a preemption-off critical section, or in
	123	* a thread that is bound to the current CPU.)
1da177e4	124	*
39c715b7 IM	125	* NOTE: raw_smp_processor_id() is for internal use only
	126	* (smp_processor_id() is the preferred variant), but in rare
	127	* instances it might also be used to turn off false positives
	128	* (i.e. smp_processor_id() use that the debugging code reports but
	129	* which use for some reason is legal). Don't use this to hack around
	130	* the warning message, as your code might not work under PREEMPT.
1da177e4	131	*/
39c715b7 IM	132	#ifdef CONFIG_DEBUG_PREEMPT
	133	extern unsigned int debug_smp_processor_id(void);
	134	# define smp_processor_id() debug_smp_processor_id()
1da177e4	135	#else
39c715b7	136	# define smp_processor_id() raw_smp_processor_id()
1da177e4 LT	137	#endif
	138
	139	#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
	140	#define put_cpu() preempt_enable()
	141	#define put_cpu_no_resched() preempt_enable_no_resched()
	142
	143	#endif /* __LINUX_SMP_H */