From 903416521c130289b769af87a70e19c2bbbff3aa Mon Sep 17 00:00:00 2001

From: Stefan Hajnoczi <stefanha@redhat.com>

Date: Fri, 22 Dec 2017 11:08:46 +0100

Subject: [PATCH 28/42] iothread: export iothread_stop()

RH-Author: Stefan Hajnoczi <stefanha@redhat.com>

Message-id: <20171222110900.24813-7-stefanha@redhat.com>

Patchwork-id: 78488

O-Subject: [RHV7.5 qemu-kvm-rhev PATCH 06/20] iothread: export iothread_stop()

Bugzilla: 1519721

RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

From: Peter Xu <peterx@redhat.com>

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: Fam Zheng <famz@redhat.com>

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Peter Xu <peterx@redhat.com>

Message-id: 20170928025958.1420-4-peterx@redhat.com

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

(cherry picked from commit 82d90705fe203cc6e150c10bd61f0dbe6979e8f4)

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 include/sysemu/iothread.h |  1 +

 iothread.c                | 24 ++++++++++++++++--------

 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/include/sysemu/iothread.h b/include/sysemu/iothread.h

index b07663f..110329b 100644

--- a/include/sysemu/iothread.h

+++ b/include/sysemu/iothread.h

@@ -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 */

diff --git a/iothread.c b/iothread.c

index 0672a91..b3c092b 100644

--- a/iothread.c

+++ b/iothread.c

@@ -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)

-- 

1.8.3.1