smpboot: Remove cpumask from the API

Now that the sole use of the whole smpboot_*cpumask() API is gone,
remove it.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/include/linux/smpboot.h b/include/linux/smpboot.h
index c174844cf663eaf7df5ab1f3d856919d557aac4b..d0884b52500100b92ae4829e070ab3a9993af4b3 100644 (file)
--- a/include/linux/smpboot.h
+++ b/include/linux/smpboot.h
@@ -25,8 +25,6 @@ struct smpboot_thread_data;
  *                     parked (cpu offline)
  * @unpark:            Optional unpark function, called when the thread is
  *                     unparked (cpu online)
- * @cpumask:           Internal state.  To update which threads are unparked,
- *                     call smpboot_update_cpumask_percpu_thread().
  * @selfparking:       Thread is not parked by the park function.
  * @thread_comm:       The base name of the thread
  */
@@ -40,23 +38,12 @@ struct smp_hotplug_thread {
        void                            (*cleanup)(unsigned int cpu, bool online);
        void                            (*park)(unsigned int cpu);
        void                            (*unpark)(unsigned int cpu);
-       cpumask_var_t                   cpumask;
        bool                            selfparking;
        const char                      *thread_comm;
 };
 
-int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread,
-                                          const struct cpumask *cpumask);
-
-static inline int
-smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread)
-{
-       return smpboot_register_percpu_thread_cpumask(plug_thread,
-                                                     cpu_possible_mask);
-}
+int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread);
 
 void smpboot_unregister_percpu_thread(struct smp_hotplug_thread *plug_thread);
-void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread,
-                                         const struct cpumask *);
 
 #endif

diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index 5043e7433f4b15879a6498ed3d1ca6cfa2876f83..c230c2dd48e19753078d9bd9b7b9b463ff81c14f 100644 (file)
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -238,8 +238,7 @@ int smpboot_unpark_threads(unsigned int cpu)
 
        mutex_lock(&smpboot_threads_lock);
        list_for_each_entry(cur, &hotplug_threads, list)
-               if (cpumask_test_cpu(cpu, cur->cpumask))
-                       smpboot_unpark_thread(cur, cpu);
+               smpboot_unpark_thread(cur, cpu);
        mutex_unlock(&smpboot_threads_lock);
        return 0;
 }
@@ -280,34 +279,26 @@ static void smpboot_destroy_threads(struct smp_hotplug_thread *ht)
 }
 
 /**
- * smpboot_register_percpu_thread_cpumask - Register a per_cpu thread related
+ * smpboot_register_percpu_thread - Register a per_cpu thread related
  *                                         to hotplug
  * @plug_thread:       Hotplug thread descriptor
- * @cpumask:           The cpumask where threads run
  *
  * Creates and starts the threads on all online cpus.
  */
-int smpboot_register_percpu_thread_cpumask(struct smp_hotplug_thread *plug_thread,
-                                          const struct cpumask *cpumask)
+int smpboot_register_percpu_thread(struct smp_hotplug_thread *plug_thread)
 {
        unsigned int cpu;
        int ret = 0;
 
-       if (!alloc_cpumask_var(&plug_thread->cpumask, GFP_KERNEL))
-               return -ENOMEM;
-       cpumask_copy(plug_thread->cpumask, cpumask);
-
        get_online_cpus();
        mutex_lock(&smpboot_threads_lock);
        for_each_online_cpu(cpu) {
                ret = __smpboot_create_thread(plug_thread, cpu);
                if (ret) {
                        smpboot_destroy_threads(plug_thread);
-                       free_cpumask_var(plug_thread->cpumask);
                        goto out;
                }
-               if (cpumask_test_cpu(cpu, cpumask))
-                       smpboot_unpark_thread(plug_thread, cpu);
+               smpboot_unpark_thread(plug_thread, cpu);
        }
        list_add(&plug_thread->list, &hotplug_threads);
 out:
@@ -315,7 +306,7 @@ out:
        put_online_cpus();
        return ret;
 }
-EXPORT_SYMBOL_GPL(smpboot_register_percpu_thread_cpumask);
+EXPORT_SYMBOL_GPL(smpboot_register_percpu_thread);
 
 /**
  * smpboot_unregister_percpu_thread - Unregister a per_cpu thread related to hotplug
@@ -331,44 +322,9 @@ void smpboot_unregister_percpu_thread(struct smp_hotplug_thread *plug_thread)
        smpboot_destroy_threads(plug_thread);
        mutex_unlock(&smpboot_threads_lock);
        put_online_cpus();
-       free_cpumask_var(plug_thread->cpumask);
 }
 EXPORT_SYMBOL_GPL(smpboot_unregister_percpu_thread);
 
-/**
- * smpboot_update_cpumask_percpu_thread - Adjust which per_cpu hotplug threads stay parked
- * @plug_thread:       Hotplug thread descriptor
- * @new:               Revised mask to use
- *
- * The cpumask field in the smp_hotplug_thread must not be updated directly
- * by the client, but only by calling this function.
- * This function can only be called on a registered smp_hotplug_thread.
- */
-void smpboot_update_cpumask_percpu_thread(struct smp_hotplug_thread *plug_thread,
-                                         const struct cpumask *new)
-{
-       struct cpumask *old = plug_thread->cpumask;
-       static struct cpumask tmp;
-       unsigned int cpu;
-
-       lockdep_assert_cpus_held();
-       mutex_lock(&smpboot_threads_lock);
-
-       /* Park threads that were exclusively enabled on the old mask. */
-       cpumask_andnot(&tmp, old, new);
-       for_each_cpu_and(cpu, &tmp, cpu_online_mask)
-               smpboot_park_thread(plug_thread, cpu);
-
-       /* Unpark threads that are exclusively enabled on the new mask. */
-       cpumask_andnot(&tmp, new, old);
-       for_each_cpu_and(cpu, &tmp, cpu_online_mask)
-               smpboot_unpark_thread(plug_thread, cpu);
-
-       cpumask_copy(old, new);
-
-       mutex_unlock(&smpboot_threads_lock);
-}
-
 static DEFINE_PER_CPU(atomic_t, cpu_hotplug_state) = ATOMIC_INIT(CPU_POST_DEAD);
 
 /*