mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-02 05:27:00 +07:00
3da1c84c00
workqueue_cpu_callback(CPU_DEAD) flushes cwq->thread under cpu_maps_update_begin(). This means that the multithreaded workqueues can't use get_online_cpus() due to the possible deadlock, very bad and very old problem. Introduce the new state, CPU_POST_DEAD, which is called after cpu_hotplug_done() but before cpu_maps_update_done(). Change workqueue_cpu_callback() to use CPU_POST_DEAD instead of CPU_DEAD. This means that create/destroy functions can't rely on get_online_cpus() any longer and should take cpu_add_remove_lock instead. [akpm@linux-foundation.org: fix CONFIG_SMP=n] Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Gautham R Shenoy <ego@in.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Paul Menage <menage@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
154 lines
4.0 KiB
C
154 lines
4.0 KiB
C
/*
|
|
* 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
|
|
* and system devices are handled in drivers/base/sys.c.
|
|
*
|
|
* CPUs are exported via sysfs in the class/cpu/devices/
|
|
* directory.
|
|
*
|
|
* Per-cpu interfaces can be implemented using a struct device_interface.
|
|
* See the following for how to do this:
|
|
* - drivers/base/intf.c
|
|
* - Documentation/driver-model/interface.txt
|
|
*/
|
|
#ifndef _LINUX_CPU_H_
|
|
#define _LINUX_CPU_H_
|
|
|
|
#include <linux/sysdev.h>
|
|
#include <linux/node.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/mutex.h>
|
|
|
|
struct cpu {
|
|
int node_id; /* The node which contains the CPU */
|
|
int hotpluggable; /* creates sysfs control file if hotpluggable */
|
|
struct sys_device sysdev;
|
|
};
|
|
|
|
extern int register_cpu(struct cpu *cpu, int num);
|
|
extern struct sys_device *get_cpu_sysdev(unsigned cpu);
|
|
|
|
extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
|
|
extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
|
|
|
|
extern int cpu_add_sysdev_attr_group(struct attribute_group *attrs);
|
|
extern void cpu_remove_sysdev_attr_group(struct attribute_group *attrs);
|
|
|
|
extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls);
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
extern void unregister_cpu(struct cpu *cpu);
|
|
#endif
|
|
struct notifier_block;
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* Need to know about CPUs going up/down? */
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
extern int register_cpu_notifier(struct notifier_block *nb);
|
|
extern void unregister_cpu_notifier(struct notifier_block *nb);
|
|
#else
|
|
|
|
#ifndef MODULE
|
|
extern int register_cpu_notifier(struct notifier_block *nb);
|
|
#else
|
|
static inline int register_cpu_notifier(struct notifier_block *nb)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static inline void unregister_cpu_notifier(struct notifier_block *nb)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
int cpu_up(unsigned int cpu);
|
|
extern void cpu_hotplug_init(void);
|
|
extern void cpu_maps_update_begin(void);
|
|
extern void cpu_maps_update_done(void);
|
|
|
|
#else /* CONFIG_SMP */
|
|
|
|
static inline int register_cpu_notifier(struct notifier_block *nb)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void unregister_cpu_notifier(struct notifier_block *nb)
|
|
{
|
|
}
|
|
|
|
static inline void cpu_hotplug_init(void)
|
|
{
|
|
}
|
|
|
|
static inline void cpu_maps_update_begin(void)
|
|
{
|
|
}
|
|
|
|
static inline void cpu_maps_update_done(void)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_SMP */
|
|
extern struct sysdev_class cpu_sysdev_class;
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
/* Stop CPUs going up and down. */
|
|
|
|
static inline void cpuhotplug_mutex_lock(struct mutex *cpu_hp_mutex)
|
|
{
|
|
mutex_lock(cpu_hp_mutex);
|
|
}
|
|
|
|
static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex)
|
|
{
|
|
mutex_unlock(cpu_hp_mutex);
|
|
}
|
|
|
|
extern void get_online_cpus(void);
|
|
extern void put_online_cpus(void);
|
|
#define hotcpu_notifier(fn, pri) { \
|
|
static struct notifier_block fn##_nb __cpuinitdata = \
|
|
{ .notifier_call = fn, .priority = pri }; \
|
|
register_cpu_notifier(&fn##_nb); \
|
|
}
|
|
#define register_hotcpu_notifier(nb) register_cpu_notifier(nb)
|
|
#define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
|
|
int cpu_down(unsigned int cpu);
|
|
|
|
#else /* CONFIG_HOTPLUG_CPU */
|
|
|
|
static inline void cpuhotplug_mutex_lock(struct mutex *cpu_hp_mutex)
|
|
{ }
|
|
static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex)
|
|
{ }
|
|
|
|
#define get_online_cpus() do { } while (0)
|
|
#define put_online_cpus() do { } while (0)
|
|
#define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
|
|
/* These aren't inline functions due to a GCC bug. */
|
|
#define register_hotcpu_notifier(nb) ({ (void)(nb); 0; })
|
|
#define unregister_hotcpu_notifier(nb) ({ (void)(nb); })
|
|
#endif /* CONFIG_HOTPLUG_CPU */
|
|
|
|
#ifdef CONFIG_PM_SLEEP_SMP
|
|
extern int suspend_cpu_hotplug;
|
|
|
|
extern int disable_nonboot_cpus(void);
|
|
extern void enable_nonboot_cpus(void);
|
|
#else /* !CONFIG_PM_SLEEP_SMP */
|
|
#define suspend_cpu_hotplug 0
|
|
|
|
static inline int disable_nonboot_cpus(void) { return 0; }
|
|
static inline void enable_nonboot_cpus(void) {}
|
|
#endif /* !CONFIG_PM_SLEEP_SMP */
|
|
|
|
#endif /* _LINUX_CPU_H_ */
|