nntp: simplify re-arming/requeue logic

We can be smarter about requeuing clients to run and avoid
excessive epoll_ctl calls since we can trust event_step to do
the right thing depending on the state of the client.

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index 42fbb255782b8d91e5fc2c85376988f3065e4900..468a22f529673b2aa0043fdb2d9b92237312b272 100644 (file)
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -58,6 +58,11 @@ sub next_tick () {
        }
 }
 
+sub requeue ($) {
+       push @$nextq, $_[0];
+       $nextt ||= PublicInbox::EvCleanup::asap(*next_tick);
+}
+
 sub update_idle_time ($) {
        my ($self) = @_;
        my $sock = $self->{sock} or return;
@@ -633,7 +638,7 @@ sub long_response ($$) {
                        }
                        if ($self->{sock}) {
                                update_idle_time($self);
-                               check_read($self);
+                               requeue($self);
                        } else {
                                out($self, " deferred[$fd] aborted - %0.6f",
                                           now() - $t0);
@@ -642,14 +647,12 @@ sub long_response ($$) {
                        # no recursion, schedule another call ASAP
                        # but only after all pending writes are done
                        update_idle_time($self);
-
-                       push @$nextq, $self;
-                       $nextt ||= PublicInbox::EvCleanup::asap(*next_tick);
+                       requeue($self);
                } else { # all done!
                        delete $self->{long_res};
-                       check_read($self);
                        res($self, '.');
                        out($self, " deferred[$fd] done - %0.6f", now() - $t0);
+                       requeue($self);
                }
        };
        $self->{long_res}->(); # kick off!
@@ -930,6 +933,7 @@ sub out ($$;@) {
        printf { $self->{nntpd}->{out} } $fmt."\n", @args;
 }
 
+# callback used by PublicInbox::DS for any (e)poll (in/out/hup/err)
 sub event_step {
        my ($self) = @_;
 
@@ -965,24 +969,7 @@ sub event_step {
 
        # maybe there's more pipelined data, or we'll have
        # to register it for socket-readiness notifications
-       check_read($self) unless ($self->{long_res} || $self->{wbuf});
-}
-
-sub check_read {
-       my ($self) = @_;
-       if (index($self->{rbuf}, "\n") >= 0) {
-               # Force another read if there is a pipelined request.
-               # We don't know if the socket has anything for us to read,
-               # and we must double-check again by the time the timer fires
-               # in case we really did dispatch a read event and started
-               # another long response.
-               push @$nextq, $self;
-               $nextt ||= PublicInbox::EvCleanup::asap(*next_tick);
-       } else {
-               # no pipelined requests available, let the kernel know
-               # to wake us up if there's more
-               $self->watch_in1; # PublicInbox::DS::watch_in1
-       }
+       requeue($self) unless ($self->{long_res} || $self->{wbuf});
 }
 
 sub not_idle_long ($$) {