#ifndef __LINUX_SMP_H #define __LINUX_SMP_H /* * Generic SMP support * Alan Cox. <alan@redhat.com> */ #include <linux/errno.h> #include <linux/types.h> #include <linux/list.h> #include <linux/cpumask.h> #include <linux/init.h> #include <linux/irqflags.h> extern void cpu_idle(void); typedef void (*smp_call_func_t)(void *info); struct call_single_data { struct list_head list; smp_call_func_t func; void *info; u16 flags; }; /* total number of cpus in this system (may exceed NR_CPUS) */ extern unsigned int total_cpus; int smp_call_function_single(int cpuid, smp_call_func_t func, void *info, int wait); #ifdef CONFIG_SMP #include <linux/preempt.h> #include <linux/kernel.h> #include <linux/compiler.h> #include <linux/thread_info.h> #include <asm/smp.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, struct task_struct *tidle); /* * Final polishing of CPUs */ extern void smp_cpus_done(unsigned int max_cpus); /* * Call a function on all other processors */ int smp_call_function(smp_call_func_t func, void *info, int wait); void smp_call_function_many(const struct cpumask *mask, smp_call_func_t func, void *info, bool wait); void __smp_call_function_single(int cpuid, struct call_single_data *data, int wait); int smp_call_function_any(const struct cpumask *mask, smp_call_func_t func, void *info, int wait); void kick_all_cpus_sync(void); /* * Generic and arch helpers */ #ifdef CONFIG_USE_GENERIC_SMP_HELPERS void __init call_function_init(void); void generic_smp_call_function_single_interrupt(void); #define generic_smp_call_function_interrupt \ generic_smp_call_function_single_interrupt #else static inline void call_function_init(void) { } #endif /* * Call a function on all processors */ int on_each_cpu(smp_call_func_t func, void *info, int wait); /* * Call a function on processors specified by mask, which might include * the local one. */ void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func, void *info, bool wait); /* * Call a function on each processor for which the supplied function * cond_func returns a positive value. This may include the local * processor. */ void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), smp_call_func_t func, void *info, bool wait, gfp_t gfp_flags); /* * 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); extern unsigned int setup_max_cpus; extern void __init setup_nr_cpu_ids(void); extern void __init smp_init(void); #else /* !SMP */ static inline void smp_send_stop(void) { } /* * These macros fold the SMP functionality into a single CPU system */ #define raw_smp_processor_id() 0 static inline int up_smp_call_function(smp_call_func_t func, void *info) { return 0; } #define smp_call_function(func, info, wait) \ (up_smp_call_function(func, info)) static inline int on_each_cpu(smp_call_func_t func, void *info, int wait) { unsigned long flags; local_irq_save(flags); func(info); local_irq_restore(flags); return 0; } /* * Note we still need to test the mask even for UP * because we actually can get an empty mask from * code that on SMP might call us without the local * CPU in the mask. */ #define on_each_cpu_mask(mask, func, info, wait) \ do { \ if (cpumask_test_cpu(0, (mask))) { \ local_irq_disable(); \ (func)(info); \ local_irq_enable(); \ } \ } while (0) /* * Preemption is disabled here to make sure the cond_func is called under the * same condtions in UP and SMP. */ #define on_each_cpu_cond(cond_func, func, info, wait, gfp_flags)\ do { \ void *__info = (info); \ preempt_disable(); \ if ((cond_func)(0, __info)) { \ local_irq_disable(); \ (func)(__info); \ local_irq_enable(); \ } \ preempt_enable(); \ } while (0) static inline void smp_send_reschedule(int cpu) { } #define smp_prepare_boot_cpu() do {} while (0) #define smp_call_function_many(mask, func, info, wait) \ (up_smp_call_function(func, info)) static inline void call_function_init(void) { } static inline int smp_call_function_any(const struct cpumask *mask, smp_call_func_t func, void *info, int wait) { return smp_call_function_single(0, func, info, wait); } static inline void kick_all_cpus_sync(void) { } #endif /* !SMP */ /* * smp_processor_id(): get the current CPU ID. * * if DEBUG_PREEMPT is enabled then 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() /* * Callback to arch code if there's nosmp or maxcpus=0 on the * boot command line: */ extern void arch_disable_smp_support(void); void smp_setup_processor_id(void); #endif /* __LINUX_SMP_H */