On 06/20/2016 01:24 PM, Jason Wang wrote:
On 2016年06月20日 11:27, Zhang Chen wrote:
On 06/20/2016 11:03 AM, Jason Wang wrote:
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?
I feel it seems can work, and will try it.
but I don't know how this change in qemu's QIOChannel code
will affect the other code. needs other people confirm it?
Yes, we need convince them. I believe we don't do this in the past is
because there's no users.
If no affect and works good,I will send a independent patch
for this.
Right, if it works, please send a RFC and explain why it is needed.
Hi~ Jason.
It work! I have send a patch for this and signed-off-by you:
[RFC PATCH] Change g_source_attach(xx, NULL) to g_souce_attach(xx,
g_main_context_get_thread_default())
But I find a problem when fix colo-compare.
if we want poll and handle chardev in compare thread,
we must use g_main_loop_run(compare_loop). and this function
block here, we can not run other job in compare thread...
like that:
static void *colo_compare_thread(void *opaque)
{
.......
worker_context = g_main_context_new();
g_main_context_push_thread_default(worker_context);
qemu_chr_add_handlers(s->chr_pri_in, compare_chr_can_read,
compare_pri_chr_in, NULL, s);
qemu_chr_add_handlers(s->chr_sec_in, compare_chr_can_read,
compare_sec_chr_in, NULL, s);
compare_loop = g_main_loop_new(worker_context, FALSE);
g_main_loop_run(compare_loop);
//will block here...
while (s->thread_status == COMPARE_THREAD_RUNNING) {
qemu_event_wait(&s->event);
qemu_event_reset(&s->event);
rcu_read_lock();
g_queue_foreach(&s->conn_list, colo_compare_connection, s);
rcu_read_unlock();
}
.....
Have any comments?