/* SPDX-License-Identifier: GPL-2.0 */
/*
* include/linux/cpu.h - generic cpu definition
*
* This is mainly for topological representation. We define the
* basic 'struct cpu' here, which can be embedded in per-arch
* definitions of processors.
*
* Basic handling of the devices is done in drivers/base/cpu.c
*
* CPUs are exported via sysfs in the devices/system/cpu
* directory.
*/
#ifndef _LINUX_CPU_H_
#define _LINUX_CPU_H_
#include <linux/node.h>
#include <linux/compiler.h>
#include <linux/cpumask.h>
#include <linux/cpuhotplug.h>
struct device;
struct device_node;
struct attribute_group;
struct cpu {
int node_id; /* The node which contains the CPU */
int hotpluggable; /* creates sysfs control file if hotpluggable */
struct device dev;
};
extern void boot_cpu_init(void);
extern void boot_cpu_hotplug_init(void);
extern void cpu_init(void);
extern void trap_init(void);
extern int register_cpu(struct cpu *cpu, int num);
extern struct device *get_cpu_device(unsigned cpu);
extern bool cpu_is_hotpluggable(unsigned cpu);
extern bool arch_match_cpu_phys_id(int cpu, u64 phys_id);
extern bool arch_find_n_match_cpu_physical_id(struct device_node *cpun,
int cpu, unsigned int *thread);
extern int cpu_add_dev_attr(struct device_attribute *attr);
extern void cpu_remove_dev_attr(struct device_attribute *attr);
extern int cpu_add_dev_attr_group(struct attribute_group *attrs);
extern void cpu_remove_dev_attr_group(struct attribute_group *attrs);
extern ssize_t cpu_show_meltdown(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_spectre_v1(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_spectre_v2(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_spec_store_bypass(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_l1tf(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_mds(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_tsx_async_abort(struct device *dev,
struct device_attribute *attr,
char *buf);
extern ssize_t cpu_show_itlb_multihit(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_srbds(struct device *dev, struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_mmio_stale_data(struct device *dev,
struct device_attribute *attr,
char *buf);
extern ssize_t cpu_show_retbleed(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_spec_rstack_overflow(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_gds(struct device *dev,
struct device_attribute *attr, char *buf);
extern __printf(4, 5)
struct device *cpu_device_create(struct device *parent, void *drvdata,
const struct attribute_group **groups,
const char *fmt, ...);
#ifdef CONFIG_HOTPLUG_CPU
extern void unregister_cpu(struct cpu *cpu);
extern ssize_t arch_cpu_probe(const char *, size_t);
extern ssize_t arch_cpu_release(const char *, size_t);
#endif
/*
* These states are not related to the core CPU hotplug mechanism. They are
* used by various (sub)architectures to track internal state
*/
#define CPU_ONLINE 0x0002 /* CPU is up */
#define CPU_UP_PREPARE 0x0003 /* CPU coming up */
#define CPU_DEAD 0x0007 /* CPU dead */
#define CPU_DEAD_FROZEN 0x0008 /* CPU timed out on unplug */
#define CPU_POST_DEAD 0x0009 /* CPU successfully unplugged */
#define CPU_BROKEN 0x000B /* CPU did not die properly */
#ifdef CONFIG_SMP
extern bool cpuhp_tasks_frozen;
int add_cpu(unsigned int cpu);
int cpu_device_up(struct device *dev);
void notify_cpu_starting(unsigned int cpu);
extern void cpu_maps_update_begin(void);
extern void cpu_maps_update_done(void);
int bringup_hibernate_cpu(unsigned int sleep_cpu);
void bringup_nonboot_cpus(unsigned int setup_max_cpus);
#else /* CONFIG_SMP */
#define cpuhp_tasks_frozen 0
static inline void cpu_maps_update_begin(void)
{
}
static inline void cpu_maps_update_done(void)
{
}
static inline int add_cpu(unsigned int cpu) { return 0;}
#endif /* CONFIG_SMP */
extern struct bus_type cpu_subsys;
extern int lockdep_is_cpus_held(void);
#ifdef CONFIG_HOTPLUG_CPU
extern void cpus_write_lock(void);
extern void cpus_write_unlock(void);
extern void cpus_read_lock(void);
extern void cpus_read_unlock(void);
extern int cpus_read_trylock(void);
extern void lockdep_assert_cpus_held(void);
extern void cpu_hotplug_disable(void);
extern void cpu_hotplug_enable(void);
void clear_tasks_mm_cpumask(int cpu);
int remove_cpu(unsigned int cpu);
int cpu_device_down(struct device *dev);
extern void smp_shutdown_nonboot_cpus(unsigned int primary_cpu);
#else /* CONFIG_HOTPLUG_CPU */
static inline void cpus_write_lock(void) { }
static inline void cpus_write_unlock(void) { }
static inline void cpus_read_lock(void) { }
static inline void cpus_read_unlock(void) { }
static inline int cpus_read_trylock(void) { return true; }
static inline void lockdep_assert_cpus_held(void) { }
static inline void cpu_hotplug_disable(void) { }
static inline void cpu_hotplug_enable(void) { }
static inline int remove_cpu(unsigned int cpu) { return -EPERM; }
static inline void smp_shutdown_nonboot_cpus(unsigned int primary_cpu) { }
#endif /* !CONFIG_HOTPLUG_CPU */
#ifdef CONFIG_PM_SLEEP_SMP
extern int freeze_secondary_cpus(int primary);
extern void thaw_secondary_cpus(void);
static inline int suspend_disable_secondary_cpus(void)
{
int cpu = 0;
if (IS_ENABLED(CONFIG_PM_SLEEP_SMP_NONZERO_CPU))
cpu = -1;
return freeze_secondary_cpus(cpu);
}
static inline void suspend_enable_secondary_cpus(void)
{
return thaw_secondary_cpus();
}
#else /* !CONFIG_PM_SLEEP_SMP */
static inline void thaw_secondary_cpus(void) {}
static inline int suspend_disable_secondary_cpus(void) { return 0; }
static inline void suspend_enable_secondary_cpus(void) { }
#endif /* !CONFIG_PM_SLEEP_SMP */
void __noreturn cpu_startup_entry(enum cpuhp_state state);
void cpu_idle_poll_ctrl(bool enable);
bool cpu_in_idle(unsigned long pc);
void arch_cpu_idle(void);
void arch_cpu_idle_prepare(void);
void arch_cpu_idle_enter(void);
void arch_cpu_idle_exit(void);
void __noreturn arch_cpu_idle_dead(void);
#ifdef CONFIG_ARCH_HAS_CPU_FINALIZE_INIT
void arch_cpu_finalize_init(void);
#else
static inline void arch_cpu_finalize_init(void) { }
#endif
void cpu_set_state_online(int cpu);
void play_idle_precise(u64 duration_ns, u64 latency_ns);
static inline void play_idle(unsigned long duration_us)
{
play_idle_precise(duration_us * NSEC_PER_USEC, U64_MAX);
}
#ifdef CONFIG_HOTPLUG_CPU
void cpuhp_report_idle_dead(void);
#else
static inline void cpuhp_report_idle_dead(void) { }
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
enum cpuhp_smt_control {
CPU_SMT_ENABLED,
CPU_SMT_DISABLED,
CPU_SMT_FORCE_DISABLED,
CPU_SMT_NOT_SUPPORTED,
CPU_SMT_NOT_IMPLEMENTED,
};
#if defined(CONFIG_SMP) && defined(CONFIG_HOTPLUG_SMT)
extern enum cpuhp_smt_control cpu_smt_control;
extern void cpu_smt_disable(bool force);
extern void cpu_smt_check_topology(void);
extern bool cpu_smt_possible(void);
extern int cpuhp_smt_enable(void);
extern int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval);
#else
# define cpu_smt_control (CPU_SMT_NOT_IMPLEMENTED)
static inline void cpu_smt_disable(bool force) { }
static inline void cpu_smt_check_topology(void) { }
static inline bool cpu_smt_possible(void) { return false; }
static inline int cpuhp_smt_enable(void) { return 0; }
static inline int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) { return 0; }
#endif
extern bool cpu_mitigations_off(void);
extern bool cpu_mitigations_auto_nosmt(void);
#endif /* _LINUX_CPU_H_ */