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Diffstat (limited to 'include/linux/smp.h')
-rw-r--r-- | include/linux/smp.h | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/include/linux/smp.h b/include/linux/smp.h new file mode 100644 index 000000000000..dcf1db3b35d3 --- /dev/null +++ b/include/linux/smp.h @@ -0,0 +1,139 @@ +#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 + */ + +#if !defined(__smp_processor_id) || !defined(CONFIG_PREEMPT) +# define smp_processor_id() 0 +#endif +#define hard_smp_processor_id() 0 +#define smp_call_function(func,info,retry,wait) ({ 0; }) +#define on_each_cpu(func,info,retry,wait) ({ func(info); 0; }) +static inline void smp_send_reschedule(int cpu) { } +#define num_booting_cpus() 1 +#define smp_prepare_boot_cpu() do {} while (0) + +#endif /* !SMP */ + +/* + * DEBUG_PREEMPT support: check whether smp_processor_id() is being + * used in a preemption-safe way. + * + * An architecture has to enable this debugging code explicitly. + * It can do so by renaming the smp_processor_id() macro to + * __smp_processor_id(). This should only be done after some minimal + * testing, because usually there are a number of false positives + * that an architecture will trigger. + * + * To fix a false positive (i.e. smp_processor_id() use that the + * debugging code reports but which use for some reason is legal), + * change the smp_processor_id() reference to _smp_processor_id(), + * which is the nondebug variant. NOTE: don't use this to hack around + * real bugs. + */ +#ifdef __smp_processor_id +# if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT) + extern unsigned int smp_processor_id(void); +# else +# define smp_processor_id() __smp_processor_id() +# endif +# define _smp_processor_id() __smp_processor_id() +#else +# define _smp_processor_id() 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 */ |