| /* SPDX-License-Identifier: GPL-2.0 */ |
| #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/smp_types.h> |
| |
| typedef void (*smp_call_func_t)(void *info); |
| typedef bool (*smp_cond_func_t)(int cpu, void *info); |
| |
| /* |
| * structure shares (partial) layout with struct irq_work |
| */ |
| struct __call_single_data { |
| struct __call_single_node node; |
| smp_call_func_t func; |
| void *info; |
| }; |
| |
| #define CSD_INIT(_func, _info) \ |
| (struct __call_single_data){ .func = (_func), .info = (_info), } |
| |
| /* Use __aligned() to avoid to use 2 cache lines for 1 csd */ |
| typedef struct __call_single_data call_single_data_t |
| __aligned(sizeof(struct __call_single_data)); |
| |
| #define INIT_CSD(_csd, _func, _info) \ |
| do { \ |
| *(_csd) = CSD_INIT((_func), (_info)); \ |
| } while (0) |
| |
| /* |
| * Enqueue a llist_node on the call_single_queue; be very careful, read |
| * flush_smp_call_function_queue() in detail. |
| */ |
| extern void __smp_call_single_queue(int cpu, struct llist_node *node); |
| |
| /* 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); |
| |
| /* |
| * Call a function on all processors |
| */ |
| void 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(smp_cond_func_t cond_func, smp_call_func_t func, |
| void *info, bool wait); |
| |
| void on_each_cpu_cond_mask(smp_cond_func_t cond_func, smp_call_func_t func, |
| void *info, bool wait, const struct cpumask *mask); |
| |
| int smp_call_function_single_async(int cpu, call_single_data_t *csd); |
| |
| #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 |
| */ |
| void 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); |
| |
| int smp_call_function_any(const struct cpumask *mask, |
| smp_call_func_t func, void *info, int wait); |
| |
| void kick_all_cpus_sync(void); |
| void wake_up_all_idle_cpus(void); |
| |
| /* |
| * Generic and arch 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 |
| |
| /* |
| * 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); |
| |
| extern int __boot_cpu_id; |
| |
| static inline int get_boot_cpu_id(void) |
| { |
| return __boot_cpu_id; |
| } |
| |
| #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 void up_smp_call_function(smp_call_func_t func, void *info) |
| { |
| } |
| #define smp_call_function(func, info, wait) \ |
| (up_smp_call_function(func, info)) |
| |
| 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) { } |
| static inline void wake_up_all_idle_cpus(void) { } |
| |
| #ifdef CONFIG_UP_LATE_INIT |
| extern void __init up_late_init(void); |
| static inline void smp_init(void) { up_late_init(); } |
| #else |
| static inline void smp_init(void) { } |
| #endif |
| |
| static inline int get_boot_cpu_id(void) |
| { |
| return 0; |
| } |
| |
| #endif /* !SMP */ |
| |
| /** |
| * raw_processor_id() - get the current (unstable) CPU id |
| * |
| * For then you know what you are doing and need an unstable |
| * CPU id. |
| */ |
| |
| /** |
| * smp_processor_id() - get the current (stable) CPU id |
| * |
| * This is the normal accessor to the CPU id and should be used |
| * whenever possible. |
| * |
| * The CPU id is stable when: |
| * |
| * - IRQs are disabled; |
| * - preemption is disabled; |
| * - the task is CPU affine. |
| * |
| * When CONFIG_DEBUG_PREEMPT; we verify these assumption and WARN |
| * when smp_processor_id() is used when the CPU id is not stable. |
| */ |
| |
| /* |
| * Allow the architecture to differentiate between a stable and unstable read. |
| * For example, x86 uses an IRQ-safe asm-volatile read for the unstable but a |
| * regular asm read for the stable. |
| */ |
| #ifndef __smp_processor_id |
| #define __smp_processor_id(x) raw_smp_processor_id(x) |
| #endif |
| |
| #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() __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); |
| |
| extern void arch_thaw_secondary_cpus_begin(void); |
| extern void arch_thaw_secondary_cpus_end(void); |
| |
| void smp_setup_processor_id(void); |
| |
| int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, |
| bool phys); |
| |
| /* SMP core functions */ |
| int smpcfd_prepare_cpu(unsigned int cpu); |
| int smpcfd_dead_cpu(unsigned int cpu); |
| int smpcfd_dying_cpu(unsigned int cpu); |
| |
| #endif /* __LINUX_SMP_H */ |