Note, the only think changed in event now (via 
https://svn.apache.org/viewvc?view=revision&revision=1542560)
is that event *checks* that atomics work as required for
event... if the check fails, it means that event has
been "broken" on that system, assuming it ever hit
blocked idlers, for a *long* time...

You should be seeing it in trunk as well...


On Nov 22, 2013, at 2:43 PM, Jeff Trawick <traw...@gmail.com> wrote:

> On Fri, Nov 22, 2013 at 2:39 PM, Jim Jagielski <j...@jagunet.com> wrote:
> 
> On Nov 22, 2013, at 2:22 PM, Jeff Trawick <traw...@gmail.com> wrote:
> 
> > On Sat, Nov 17, 2012 at 6:00 AM, Ruediger Pluem <rpl...@apache.org> wrote:
> >
> >
> > j...@apache.org wrote:
> > > +        i = apr_atomic_dec32(&foo);
> > > +        if (i >= 0) {
> >
> > Why can we expect i < 0? apr_atomic_dec32 returns 0 if the dec causes foo 
> > to become zero and it returns non zero
> > otherwise. Shouldn't this behavior the same across all platforms? And if 
> > not should that be fixed in APR?
> >
> > icc (Intel) builds of httpd 2.4.7 event MPM (with apr-1.5.0) bomb here.
> >
> > --enable-nonportable-atomics is specified for apr, though I haven't checked 
> > what that does with icc.
> >
> 
> As noted back with the orig update, this test is due to the
> fdqueue code in the new event:
> 
> apr_status_t ap_queue_info_set_idle(fd_queue_info_t * queue_info,
>                                     apr_pool_t * pool_to_recycle)
> {
>     apr_status_t rv;
>     int prev_idlers;
> 
>     ap_push_pool(queue_info, pool_to_recycle);
> 
>     /* Atomically increment the count of idle workers */
>     /*
>      * TODO: The atomics expect unsigned whereas we're using signed.
>      *       Need to double check that they work as expected or else
>      *       rework how we determine blocked.
>      * UPDATE: Correct operation is performed during open_logs()
>      */
>     prev_idlers = apr_atomic_inc32((apr_uint32_t *)&(queue_info->idlers));
> 
>     /* If other threads are waiting on a worker, wake one up */
>     if (prev_idlers < 0) {
> 
> 
> See the comments ("The atomics expect unsigned whereas...") for
> the reason, etc.
> 
> When you say "icc (Intel) builds of httpd 2.4.7 event MPM (with apr-1.5.0) 
> bomb here."
> do you mean that you get the 'atomics not working as expected' error
> (and the internal server error) or that it core dumps?
> 
> 
> "atomics not working as expected"
> 
> Let me see what code is used...
> 
> -- 
> Born in Roswell... married an alien...
> http://emptyhammock.com/

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