include/linux/smpboot.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_SMPBOOT_H
   3 #define _LINUX_SMPBOOT_H
   4
   5 #include <linux/types.h>
   6
   7 struct task_struct;
   8 /* Cookie handed to the thread_fn*/
   9 struct smpboot_thread_data;
  10
  11 /**
  12  * struct smp_hotplug_thread - CPU hotplug related thread descriptor
  13  * @store:              Pointer to per cpu storage for the task pointers
  14  * @list:               List head for core management
  15  * @thread_should_run:  Check whether the thread should run or not. Called with
  16  *                      preemption disabled.
  17  * @thread_fn:          The associated thread function
  18  * @create:             Optional setup function, called when the thread gets
  19  *                      created (Not called from the thread context)
  20  * @setup:              Optional setup function, called when the thread gets
  21  *                      operational the first time
  22  * @cleanup:            Optional cleanup function, called when the thread
  23  *                      should stop (module exit)
  24  * @park:               Optional park function, called when the thread is
  25  *                      parked (cpu offline)
  26  * @unpark:             Optional unpark function, called when the thread is
  27  *                      unparked (cpu online)
  28  * @cpumask:            Internal state.  To update which threads are unparked,
  29  *                      call smpboot_update_cpumask_percpu_thread().
  30  * @selfparking:        Thread is not parked by the park function.
  31  * @thread_comm:        The base name of the thread
  32  */
  33 struct smp_hotplug_thread {
  34         struct task_struct __percpu     **store;
  35         struct list_head                list;
  36         int                             (*thread_should_run)(unsigned int cpu);
  37         void                            (*thread_fn)(unsigned int cpu);
  38         void                            (*create)(unsigned int cpu);
  39         void                            (*setup)(unsigned int cpu);
  40         void                            (*cleanup)(unsigned int cpu, bool online);
  41         void                            (*park)(unsigned int cpu);
  42         void                            (*unpark)(unsigned int cpu);
  43         cpumask_var_t                   cpumask;
  44         bool                            selfparking;
  45         const char                      *thread_comm;
  46 };
  47
  48 int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread,
  49                                            const struct cpumask *cpumask);
  50
  51 static inline int
  52 smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread)
  53 {
  54         return smpboot_register_percpu_thread_cpumask(plug_thread,
  55                                                       cpu_possible_mask);
  56 }
  57
  58 void smpboot_unregister_percpu_thread(struct smp_hotplug_thread *plug_thread);
  59 void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread,
  60                                           const struct cpumask *);
  61
  62 #endif