Commit 36da91bd authored by Petr Mladek's avatar Petr Mladek Committed by Paolo Bonzini
Browse files

KVM: x86: Handle the kthread worker using the new API 



Use the new API to create and destroy the "kvm-pit" kthread
worker. The API hides some implementation details.

In particular, kthread_create_worker() allocates and initializes
struct kthread_worker. It runs the kthread the right way
and stores task_struct into the worker structure.

kthread_destroy_worker() flushes all pending works, stops
the kthread and frees the structure.

This patch does not change the existing behavior except for
dynamically allocating struct kthread_worker and storing
only the pointer of this structure.

It is compile tested only because I did not find an easy
way how to run the code. Well, it should be pretty safe
given the nature of the change.

Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
Message-Id: <1476877847-11217-1-git-send-email-pmladek@suse.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 16c2aec6

arch/x86/kvm/i8254.c

+6 −9
Original line number Diff line number Diff line
@@ -212,7 +212,7 @@ static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 
	 */

	smp_mb();

	if (atomic_dec_if_positive(&ps->pending) > 0)

		kthread_queue_work(&pit->worker, &pit->expired);

		kthread_queue_work(pit->worker, &pit->expired);

}



void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
@@ -272,7 +272,7 @@ static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) 
	if (atomic_read(&ps->reinject))

		atomic_inc(&ps->pending);



	kthread_queue_work(&pt->worker, &pt->expired);

	kthread_queue_work(pt->worker, &pt->expired);



	if (ps->is_periodic) {

		hrtimer_add_expires_ns(&ps->timer, ps->period);
@@ -667,10 +667,8 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 
	pid_nr = pid_vnr(pid);

	put_pid(pid);



	kthread_init_worker(&pit->worker);

	pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker,

				       "kvm-pit/%d", pid_nr);

	if (IS_ERR(pit->worker_task))

	pit->worker = kthread_create_worker(0, "kvm-pit/%d", pid_nr);

	if (IS_ERR(pit->worker))

		goto fail_kthread;



	kthread_init_work(&pit->expired, pit_do_work);
@@ -713,7 +711,7 @@ fail_register_speaker: 
fail_register_pit:

	mutex_unlock(&kvm->slots_lock);

	kvm_pit_set_reinject(pit, false);

	kthread_stop(pit->worker_task);

	kthread_destroy_worker(pit->worker);

fail_kthread:

	kvm_free_irq_source_id(kvm, pit->irq_source_id);

fail_request:
@@ -730,8 +728,7 @@ void kvm_free_pit(struct kvm *kvm) 
		kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->speaker_dev);

		kvm_pit_set_reinject(pit, false);

		hrtimer_cancel(&pit->pit_state.timer);

		kthread_flush_work(&pit->expired);

		kthread_stop(pit->worker_task);

		kthread_destroy_worker(pit->worker);

		kvm_free_irq_source_id(kvm, pit->irq_source_id);

		kfree(pit);

	}

arch/x86/kvm/i8254.h

+1 −2
Original line number Diff line number Diff line
@@ -44,8 +44,7 @@ struct kvm_pit { 
	struct kvm_kpit_state pit_state;

	int irq_source_id;

	struct kvm_irq_mask_notifier mask_notifier;

	struct kthread_worker worker;

	struct task_struct *worker_task;

	struct kthread_worker *worker;

	struct kthread_work expired;

};

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