Re: [Qemu-devel] [RFC PATCH V4 0/4] Introduce COLO-compare

[Jason Wang <jasowang@redhat.com>]

On 2016年06月17日 10:25, Zhang Chen wrote:
> Hi~ jason.
>
> I tried a lot of ways to make it run in compare thread, but it not work.
>
> Because that:
> void g_main_context_push_thread_default (GMainContext *context);
> Acquires context and sets it as the thread-default context for the 
> current thread.
>
> So, this function g_main_context_push_thread_default() just can set 
> thread-default context,
> not the global default context. and I can't find a function to set 
> global default context in glib.
> The qemu's QIOChannel uses g_source_attach(source, NULL); to attach 
> GSource.
> g_source_attach (GSource *source,
>                  GMainContext *context);
>
> context
> a GMainContext (if NULL, the default context will be used).
>
> But he not say "the default context" is global default context or 
> thread-default context.
> So I read glib codes find that:
> guint
> g_source_attach (GSource *source,
>                  GMainContext *context)
> {
> .....
> if (!context)
>     context = g_main_context_default ();
> .....
> }
>
> g_main_context_default ()
> Returns the global default main context.
>
> So...I think we can't make qemu_chr_add_handlers() run in colo thread 
> in this way.
> Do you have any comments about that? 

How about (like I suggest previously) just use

g_souce_attach(x, g_main_context_get_thread_default());

in qemu's QIOChannel code?