Re: [Patch 1/1] tabled: Add replication daemon

[Pete Zaitcev <zaitcev@redhat.com>]

On Thu, 03 Dec 2009 00:42:47 -0500
Jeff Garzik <jeff@garzik.org> wrote:

> On 11/26/2009 09:39 PM, Pete Zaitcev wrote:

> It seems to me you should
> 
> a) leave current main-thread libevent code unchanged
> 
> b) call event_base_new() for the new thread, passing that newly-created 
> event_base to replica thread events using event_base_set().

Isn't it exactly what I do right now?

> event_reinit() seems more appropriate for forks than threads.  tabled's 
> needs are simple -- you simply need to create an additional event_base 
> for the new thread.

It wasn't obvious from the description and anyway, what's the harm?
I thought it reopens some /dev/epoll or whatever may be necessary
in the OS.

> > +       /* Statics are a silly way to pass arguments to threads, but oh well. */
> > +       evbase = ev_base;
> > +
> > +       scan_thread = g_thread_create(rep_thread_func, NULL, FALSE, &error);  
> 
> The second argument to g_thread_create() is a user-provided data 
> pointer, passed directly to the newly created thread.  No need for a 
> static, AFAICS.

Ignoring the comment for now, the problem is that evbase is needed
in the "system context" of a thread, for things like passing it
down to stor_open(). That's the main reason why it's static.
Threads in Glib have something called "static private", which
kinda-sorta works like what we need, but it's a pain.
I guess I can try to use it...

-- Pete