From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43534) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dfjBN-0002ss-4g for qemu-devel@nongnu.org; Thu, 10 Aug 2017 04:51:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dfjBK-00033d-18 for qemu-devel@nongnu.org; Thu, 10 Aug 2017 04:51:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38096) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dfjBJ-00032k-Ny for qemu-devel@nongnu.org; Thu, 10 Aug 2017 04:51:05 -0400 Date: Thu, 10 Aug 2017 04:50:56 -0400 (EDT) From: Paolo Bonzini Message-ID: <388721916.2895219.1502355056793.JavaMail.zimbra@redhat.com> In-Reply-To: <1502411355-3943-1-git-send-email-wang.yong155@zte.com.cn> References: <1502411355-3943-1-git-send-email-wang.yong155@zte.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] qemu-iothread: IOThread supports the GMainContext event loop List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wang yong Cc: stefanha@redhat.com, famz@redhat.com, jasowang@redhat.com, wang guang55 , zhangchen fnst , zhang zhanghailiang , lizhijian@cn.fujitsu.com, qemu-devel@nongnu.org ----- Original Message ----- > From: "Wang yong" > To: pbonzini@redhat.com, stefanha@redhat.com, famz@redhat.com, jasowang@redhat.com > Cc: "wang yong155" , "wang guang55" , "zhangchen fnst" > , "zhang zhanghailiang" , lizhijian@cn.fujitsu.com, > qemu-devel@nongnu.org > Sent: Friday, August 11, 2017 2:29:15 AM > Subject: [PATCH] qemu-iothread: IOThread supports the GMainContext event loop > > From: Wang Yong > > IOThread uses AioContext event loop and does not run a GMainContext. > Therefore,chardev cannot work in IOThread,such as the chardev is > used for colo-compare packets reception. > > This patch makes the IOThread run the GMainContext event loop, > chardev and IOThread can work together. > > Signed-off-by: Wang Yong > Signed-off-by: Wang Guang Nice. Just a note, I think an iothread should have its own (optional) GMainContext accessed with iothread_get_g_main_context(iothread). When you call it for the first time, the iothread: 1) creates a GMainContext 2) adds the AioContext as a GSource in the GMainContext 3) asks iothread_run to switch from the AioContext loop to the GMainContext loop To simplify thread-safety: 1) the GMainContext can be wrapped with a GOnce 2) the GOnce callback can leave steps 2 and 3 to a bottom half. Paolo > --- > include/sysemu/iothread.h | 1 + > iothread.c | 13 +++++++++++++ > 2 files changed, 14 insertions(+) > > diff --git a/include/sysemu/iothread.h b/include/sysemu/iothread.h > index e6da1a4..ffe4e8a 100644 > --- a/include/sysemu/iothread.h > +++ b/include/sysemu/iothread.h > @@ -24,6 +24,7 @@ typedef struct { > > QemuThread thread; > AioContext *ctx; > + GMainLoop *loop; > QemuMutex init_done_lock; > QemuCond init_done_cond; /* is thread initialization done? */ > bool stopping; > diff --git a/iothread.c b/iothread.c > index beeb870..b6f3c3c 100644 > --- a/iothread.c > +++ b/iothread.c > @@ -46,6 +46,7 @@ AioContext *qemu_get_current_aio_context(void) > static void *iothread_run(void *opaque) > { > IOThread *iothread = opaque; > + GMainContext *context; > > rcu_register_thread(); > > @@ -57,6 +58,15 @@ static void *iothread_run(void *opaque) > > while (!atomic_read(&iothread->stopping)) { > aio_poll(iothread->ctx, true); > + > + context = iothread->ctx->source.context; > + if (context) { > + iothread->loop = g_main_loop_new(context, TRUE); > + g_main_loop_run(iothread->loop); > + > + g_main_loop_unref(iothread->loop); > + g_main_context_unref(context); > + } > } > > rcu_unregister_thread(); > @@ -72,6 +82,9 @@ static int iothread_stop(Object *object, void *opaque) > return 0; > } > iothread->stopping = true; > + if (iothread->loop) { > + g_main_loop_quit(iothread->loop); > + } > aio_notify(iothread->ctx); > qemu_thread_join(&iothread->thread); > return 0; > -- > 1.8.3.1 > > >