Commit 82d90705 authored by Peter Xu's avatar Peter Xu Committed by Stefan Hajnoczi
Browse files

iothread: export iothread_stop() 



So that internal iothread users can explicitly stop one iothread without
destroying it.

Since at it, fix iothread_stop() to allow it to be called multiple
times.  Before this patch we may call iothread_stop() more than once on
single iothread, while that may not be correct since qemu_thread_join()
is not allowed to run twice.  From manual of pthread_join():

  Joining with a thread that has previously been joined results in
  undefined behavior.

Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
Message-id: 20170928025958.1420-4-peterx@redhat.com
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 0173e21b

include/sysemu/iothread.h

+1 −0
Original line number Diff line number Diff line
@@ -52,6 +52,7 @@ GMainContext *iothread_get_g_main_context(IOThread *iothread); 
 * "query-iothreads".

 */

IOThread *iothread_create(const char *id, Error **errp);

void iothread_stop(IOThread *iothread);

void iothread_destroy(IOThread *iothread);



#endif /* IOTHREAD_H */

iothread.c

+16 −8
Original line number Diff line number Diff line
@@ -80,13 +80,10 @@ static void *iothread_run(void *opaque) 
    return NULL;

}



static int iothread_stop(Object *object, void *opaque)

void iothread_stop(IOThread *iothread)

{

    IOThread *iothread;



    iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD);

    if (!iothread || !iothread->ctx || iothread->stopping) {

        return 0;

    if (!iothread->ctx || iothread->stopping) {

        return;

    }

    iothread->stopping = true;

    aio_notify(iothread->ctx);
@@ -94,6 +91,17 @@ static int iothread_stop(Object *object, void *opaque) 
        g_main_loop_quit(iothread->main_loop);

    }

    qemu_thread_join(&iothread->thread);

}



static int iothread_stop_iter(Object *object, void *opaque)

{

    IOThread *iothread;



    iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD);

    if (!iothread) {

        return 0;

    }

    iothread_stop(iothread);

    return 0;

}
@@ -108,7 +116,7 @@ static void iothread_instance_finalize(Object *obj) 
{

    IOThread *iothread = IOTHREAD(obj);



    iothread_stop(obj, NULL);

    iothread_stop(iothread);

    qemu_cond_destroy(&iothread->init_done_cond);

    qemu_mutex_destroy(&iothread->init_done_lock);

    if (!iothread->ctx) {
@@ -328,7 +336,7 @@ void iothread_stop_all(void) 
        aio_context_release(ctx);

    }



    object_child_foreach(container, iothread_stop, NULL);

    object_child_foreach(container, iothread_stop_iter, NULL);

}



static gpointer iothread_g_main_context_init(gpointer opaque)