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/