Message ID | 1502411355-3943-1-git-send-email-wang.yong155@zte.com.cn |
---|---|
State | New |
Headers | show |
----- Original Message ----- > From: "Wang yong" <wang.yong155@zte.com.cn> > To: pbonzini@redhat.com, stefanha@redhat.com, famz@redhat.com, jasowang@redhat.com > Cc: "wang yong155" <wang.yong155@zte.com.cn>, "wang guang55" <wang.guang55@zte.com.cn>, "zhangchen fnst" > <zhangchen.fnst@cn.fujitsu.com>, "zhang zhanghailiang" <zhang.zhanghailiang@huawei.com>, 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<wang.yong155@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.yong155@zte.com.cn> > Signed-off-by: Wang Guang<wang.guang55@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 > > >
On Fri, 08/11 08:29, Wang yong wrote: > From: Wang Yong<wang.yong155@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.yong155@zte.com.cn> > Signed-off-by: Wang Guang<wang.guang55@zte.com.cn> > --- > 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); Is it better to set iothread->loop to NULL after unref? If in the future a second place adds g_main_loop_quit(), it can coordinate with iothread_stop by checking iothread->loop == NULL. > + g_main_context_unref(context); Where is the matching g_main_context_ref? I think the one reference in iothread->loop goes away with g_main_loop_unref. Is this line unnecessary? > + } > } > > 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 > > > Though I haven't seen the chardev changes yet, the general idea looks good to me. Fam
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;