Re: [Qemu-devel] [PATCHv5 01/03] qemu-iothread: IOThread supports theGMainContext event loop

[<wang.yong155@zte.com.cn>]

>> 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 |  4 ++++>>  iothread.c                | 45 +++++++++++++++++++++++++++++++++++++++++++++>>  2 files changed, 49 insertions(+)>> >> diff --git a/include/sysemu/iothread.h b/include/sysemu/iothread.h>> index e6da1a4..d2985b3 100644>> --- a/include/sysemu/iothread.h>> +++ b/include/sysemu/iothread.h>> @@ -24,6 +24,9 @@ typedef struct {>>  >>      QemuThread thread>>      AioContext *ctx>> +    GMainContext *worker_context>> +    GMainLoop *main_loop>> +    GOnce once>>      QemuMutex init_done_lock>>      QemuCond init_done_cond    /* is thread initialization done? */>>      bool stopping>> @@ -41,5 +44,6 @@ typedef struct {>>  char *iothread_get_id(IOThread *iothread)>>  AioContext *iothread_get_aio_context(IOThread *iothread)>>  void iothread_stop_all(void)>> +GMainContext *iothread_get_g_main_context(IOThread *iothread)>>  >>  #endif /* IOTHREAD_H */>> diff --git a/iothread.c b/iothread.c>> index beeb870..44c8944 100644>> --- a/iothread.c>> +++ b/iothread.c>> @@ -57,6 +57,23 @@ static void *iothread_run(void *opaque)>>  >>      while (!atomic_read(&iothread->stopping)) {>>          aio_poll(iothread->ctx, true)>> +>> +        if (atomic_read(&iothread->worker_context)) {>> +            GMainLoop *loop>> +>> +            g_main_context_push_thread_default(iothread->worker_context)>> +            iothread->main_loop =>> +                g_main_loop_new(iothread->worker_context, TRUE)>> +            loop = iothread->main_loop>> +>> +            g_main_loop_run(iothread->main_loop)>> +            iothread->main_loop = NULL>> +            g_main_loop_unref(loop)>> +>> +            g_main_context_pop_thread_default(iothread->worker_context)>> +            g_main_context_unref(iothread->worker_context)>> +            iothread->worker_context = NULL>> +        }>>      }>>  >>      rcu_unregister_thread()>> @@ -73,6 +90,9 @@ static int iothread_stop(Object *object, void *opaque)>>      }>>      iothread->stopping = true>>      aio_notify(iothread->ctx)>> +    if (atomic_read(&iothread->main_loop)) {>> +        g_main_loop_quit(iothread->main_loop)>> +    }>>      qemu_thread_join(&iothread->thread)>>      return 0>>  }>> @@ -125,6 +145,7 @@ static void iothread_complete(UserCreatable *obj, Error **errp)>>  >>      qemu_mutex_init(&iothread->init_done_lock)>>      qemu_cond_init(&iothread->init_done_cond)>> +    iothread->once = (GOnce) G_ONCE_INIT>>In last review I suggested removing this type cast, otherwise looks good. Drop>it and please add>>Reviewed-by: Fam Zheng <famz@redhat.com>>

Hi Fam,

Here, iothread->once can't be initialized with G_ONCE_INIT directly, must use type cast.

if  remove type cast , we will get an error.




iothread.c: In function ‘iothread_complete’:

/usr/include/glib-2.0/glib/gthread.h:101:21: error: expected expression before ‘{’ token

 #define G_ONCE_INIT { G_ONCE_STATUS_NOTCALLED, NULL }

                     ^

iothread.c:149:22: note: in expansion of macro ‘G_ONCE_INIT’

     iothread->once = G_ONCE_INIT




Thanks




>>  >>      /* This assumes we are called from a thread with useful CPU affinity for us>>       * to inherit.>> @@ -309,3 +330,27 @@ void iothread_stop_all(void)>>  >>      object_child_foreach(container, iothread_stop, NULL)>>  }>> +>> +static gpointer iothread_g_main_context_init(gpointer opaque)>> +{>> +    AioContext *ctx>> +    IOThread *iothread = opaque>> +    GSource *source>> +>> +    iothread->worker_context = g_main_context_new()>> +>> +    ctx = iothread_get_aio_context(iothread)>> +    source = aio_get_g_source(ctx)>> +    g_source_attach(source, iothread->worker_context)>> +    g_source_unref(source)>> +>> +    aio_notify(iothread->ctx)>> +    return NULL>> +}>> +>> +GMainContext *iothread_get_g_main_context(IOThread *iothread)>> +{>> +    g_once(&iothread->once, iothread_g_main_context_init, iothread)>> +>> +    return iothread->worker_context>> +}>> -- >> 1.8.3.1>> >> 



原始邮件



发件人： <famz@redhat.com>
收件人：王勇10170530
抄送人： <pbonzini@redhat.com> <stefanha@redhat.com> <jasowang@redhat.com> <zhangchen.fnst@cn.fujitsu.com> <zhang.zhanghailiang@huawei.com>王广10165992 <lizhijian@cn.fujitsu.com> <qemu-devel@nongnu.org>
日 期 ：2017年08月31日 10:18
主 题 ：Re: [PATCHv5 01/03] qemu-iothread: IOThread supports theGMainContext event loop





On Tue, 08/29 15:22, 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 |  4 ++++
>  iothread.c                | 45 +++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 49 insertions(+)
> 
> diff --git a/include/sysemu/iothread.h b/include/sysemu/iothread.h
> index e6da1a4..d2985b3 100644
> --- a/include/sysemu/iothread.h
> +++ b/include/sysemu/iothread.h
> @@ -24,6 +24,9 @@ typedef struct {
>  
>      QemuThread thread
>      AioContext *ctx
> +    GMainContext *worker_context
> +    GMainLoop *main_loop
> +    GOnce once
>      QemuMutex init_done_lock
>      QemuCond init_done_cond    /* is thread initialization done? */
>      bool stopping
> @@ -41,5 +44,6 @@ typedef struct {
>  char *iothread_get_id(IOThread *iothread)
>  AioContext *iothread_get_aio_context(IOThread *iothread)
>  void iothread_stop_all(void)
> +GMainContext *iothread_get_g_main_context(IOThread *iothread)
>  
>  #endif /* IOTHREAD_H */
> diff --git a/iothread.c b/iothread.c
> index beeb870..44c8944 100644
> --- a/iothread.c
> +++ b/iothread.c
> @@ -57,6 +57,23 @@ static void *iothread_run(void *opaque)
>  
>      while (!atomic_read(&iothread->stopping)) {
>          aio_poll(iothread->ctx, true)
> +
> +        if (atomic_read(&iothread->worker_context)) {
> +            GMainLoop *loop
> +
> +            g_main_context_push_thread_default(iothread->worker_context)
> +            iothread->main_loop =
> +                g_main_loop_new(iothread->worker_context, TRUE)
> +            loop = iothread->main_loop
> +
> +            g_main_loop_run(iothread->main_loop)
> +            iothread->main_loop = NULL
> +            g_main_loop_unref(loop)
> +
> +            g_main_context_pop_thread_default(iothread->worker_context)
> +            g_main_context_unref(iothread->worker_context)
> +            iothread->worker_context = NULL
> +        }
>      }
>  
>      rcu_unregister_thread()
> @@ -73,6 +90,9 @@ static int iothread_stop(Object *object, void *opaque)
>      }
>      iothread->stopping = true
>      aio_notify(iothread->ctx)
> +    if (atomic_read(&iothread->main_loop)) {
> +        g_main_loop_quit(iothread->main_loop)
> +    }
>      qemu_thread_join(&iothread->thread)
>      return 0
>  }
> @@ -125,6 +145,7 @@ static void iothread_complete(UserCreatable *obj, Error **errp)
>  
>      qemu_mutex_init(&iothread->init_done_lock)
>      qemu_cond_init(&iothread->init_done_cond)
> +    iothread->once = (GOnce) G_ONCE_INIT

In last review I suggested removing this type cast, otherwise looks good. Drop
it and please add

Reviewed-by: Fam Zheng <famz@redhat.com>

>  
>      /* This assumes we are called from a thread with useful CPU affinity for us
>       * to inherit.
> @@ -309,3 +330,27 @@ void iothread_stop_all(void)
>  
>      object_child_foreach(container, iothread_stop, NULL)
>  }
> +
> +static gpointer iothread_g_main_context_init(gpointer opaque)
> +{
> +    AioContext *ctx
> +    IOThread *iothread = opaque
> +    GSource *source
> +
> +    iothread->worker_context = g_main_context_new()
> +
> +    ctx = iothread_get_aio_context(iothread)
> +    source = aio_get_g_source(ctx)
> +    g_source_attach(source, iothread->worker_context)
> +    g_source_unref(source)
> +
> +    aio_notify(iothread->ctx)
> +    return NULL
> +}
> +
> +GMainContext *iothread_get_g_main_context(IOThread *iothread)
> +{
> +    g_once(&iothread->once, iothread_g_main_context_init, iothread)
> +
> +    return iothread->worker_context
> +}
> -- 
> 1.8.3.1
> 
>