ds: flatten $EXPMAP, delete entries on close

[public-inbox.git] / lib / PublicInbox / DS.pm

diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm
index 2f41ea456d72cd11854bad753761a6292243733f..970061fd55f1c44c77d51084d7d9891aeb3f48f3 100644 (file)
--- a/lib/PublicInbox/DS.pm
+++ b/lib/PublicInbox/DS.pm
@@ -39,9 +39,9 @@ use Errno qw(EAGAIN EINVAL);
 use Carp qw(confess carp);
 
 my $nextq; # queue for next_tick
-my $WaitPids; # list of [ pid, callback, callback_arg ]
-my $later_queue; # callbacks
-my $EXPMAP; # fd -> [ idle_time, $self ]
+my $wait_pids; # list of [ pid, callback, callback_arg ]
+my $later_queue; # list of callbacks to run at some later interval
+my $EXPMAP; # fd -> idle_time
 our $EXPTIME = 180; # 3 minutes
 my ($later_timer, $reap_timer, $exp_timer);
 my $ToClose; # sockets to close when event loop is done
@@ -71,8 +71,7 @@ Reset all state
 =cut
 sub Reset {
     %DescriptorMap = ();
-    $WaitPids = [];
-    $later_queue = [];
+    $wait_pids = $later_queue = undef;
     $EXPMAP = {};
     $nextq = $ToClose = $reap_timer = $later_timer = $exp_timer = undef;
     $LoopTimeout = -1;  # no timeout by default
@@ -226,25 +225,23 @@ sub RunTimers {
 }
 
 # We can't use waitpid(-1) safely here since it can hit ``, system(),
-# and other things.  So we scan the $WaitPids list, which is hopefully
-# not too big.
+# and other things.  So we scan the $wait_pids list, which is hopefully
+# not too big.  We keep $wait_pids small by not calling dwaitpid()
+# until we've hit EOF when reading the stdout of the child.
 sub reap_pids {
-    my $tmp = $WaitPids;
-    $WaitPids = [];
-    $reap_timer = undef;
+    my $tmp = $wait_pids or return;
+    $wait_pids = $reap_timer = undef;
     foreach my $ary (@$tmp) {
         my ($pid, $cb, $arg) = @$ary;
         my $ret = waitpid($pid, WNOHANG);
         if ($ret == 0) {
-            push @$WaitPids, $ary;
+            push @$wait_pids, $ary; # autovivifies @$wait_pids
         } elsif ($cb) {
             eval { $cb->($arg, $pid) };
         }
     }
-    if (@$WaitPids) {
-        # we may not be donea, and we may miss our
-        $reap_timer = add_timer(1, \&reap_pids);
-    }
+    # we may not be done, yet, and could've missed/masked a SIGCHLD:
+    $reap_timer = add_timer(1, \&reap_pids) if $wait_pids;
 }
 
 # reentrant SIGCHLD handler (since reap_pids is not reentrant)
@@ -262,9 +259,13 @@ sub PostEventLoop () {
        # loop)
        if (my $close_now = $ToClose) {
                $ToClose = undef; # will be autovivified on push
+               @$close_now = map { fileno($_) } @$close_now;
+
+               # order matters, destroy expiry times, first:
+               delete @$EXPMAP{@$close_now};
+
                # ->DESTROY methods may populate ToClose
-               delete($DescriptorMap{fileno($_)}) for @$close_now;
-               # let refcounting drop everything in $close_now at once
+               delete @DescriptorMap{@$close_now};
        }
 
        # by default we keep running, unless a postloop callback cancels it
@@ -626,62 +627,53 @@ sub shutdn ($) {
 
 # must be called with eval, PublicInbox::DS may not be loaded (see t/qspawn.t)
 sub dwaitpid ($$$) {
-    my ($pid, $cb, $arg) = @_;
-    if ($in_loop) {
-        push @$WaitPids, [ $pid, $cb, $arg ];
+       die "Not in EventLoop\n" unless $in_loop;
+       push @$wait_pids, [ @_ ]; # [ $pid, $cb, $arg ]
 
-        # We could've just missed our SIGCHLD, cover it, here:
-        requeue(\&reap_pids);
-    } else {
-        die "Not in EventLoop\n";
-    }
+       # We could've just missed our SIGCHLD, cover it, here:
+       requeue(\&reap_pids);
 }
 
 sub _run_later () {
-    my $run = $later_queue;
-    $later_timer = undef;
-    $later_queue = [];
-    $_->() for @$run;
+       my $run = $later_queue or return;
+       $later_timer = $later_queue = undef;
+       $_->() for @$run;
 }
 
 sub later ($) {
-    my ($cb) = @_;
-    push @$later_queue, $cb;
-    $later_timer //= add_timer(60, \&_run_later);
+       push @$later_queue, $_[0]; # autovivifies @$later_queue
+       $later_timer //= add_timer(60, \&_run_later);
 }
 
 sub expire_old () {
-    my $now = now();
-    my $exp = $EXPTIME;
-    my $old = $now - $exp;
-    my %new;
-    while (my ($fd, $v) = each %$EXPMAP) {
-        my ($idle_time, $ds_obj) = @$v;
-        if ($idle_time < $old) {
-            if (!$ds_obj->shutdn) {
-                $new{$fd} = $v;
-            }
-        } else {
-            $new{$fd} = $v;
-        }
-    }
-    $EXPMAP = \%new;
-    $exp_timer = scalar(keys %new) ? later(\&expire_old) : undef;
+       my $now = now();
+       my $exp = $EXPTIME;
+       my $old = $now - $exp;
+       my %new;
+       while (my ($fd, $idle_at) = each %$EXPMAP) {
+               if ($idle_at < $old) {
+                       my $ds_obj = $DescriptorMap{$fd};
+                       $new{$fd} = $idle_at if !$ds_obj->shutdn;
+               } else {
+                       $new{$fd} = $idle_at;
+               }
+       }
+       $EXPMAP = \%new;
+       $exp_timer = scalar(keys %new) ? later(\&expire_old) : undef;
 }
 
 sub update_idle_time {
-    my ($self) = @_;
-    my $sock = $self->{sock} or return;
-    $EXPMAP->{fileno($sock)} = [ now(), $self ];
-    $exp_timer //= later(\&expire_old);
+       my ($self) = @_;
+       my $sock = $self->{sock} or return;
+       $EXPMAP->{fileno($sock)} = now();
+       $exp_timer //= later(\&expire_old);
 }
 
 sub not_idle_long {
-    my ($self, $now) = @_;
-    my $sock = $self->{sock} or return;
-    my $ary = $EXPMAP->{fileno($sock)} or return;
-    my $exp_at = $ary->[0] + $EXPTIME;
-    $exp_at > $now;
+       my ($self, $now) = @_;
+       my $sock = $self->{sock} or return;
+       my $idle_at = $EXPMAP->{fileno($sock)} or return;
+       ($idle_at + $EXPTIME) > $now;
 }
 
 1;