----- Original Message -----
> From: "Wang yong" <wang.yong...@zte.com.cn>
> To: pbonz...@redhat.com, stefa...@redhat.com, f...@redhat.com,
> jasow...@redhat.com
> Cc: "wang yong155" <wang.yong...@zte.com.cn>, "wang guang55"
> <wang.guan...@zte.com.cn>, "zhangchen fnst"
> <zhangchen.f...@cn.fujitsu.com>, "zhang zhanghailiang"
> <zhang.zhanghaili...@huawei.com>, lizhij...@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<wang.yong...@zte.com.cn>
>
> 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<wang.yong...@zte.com.cn>
> Signed-off-by: Wang Guang<wang.guan...@zte.com.cn>
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
>
>
>
