X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FIPC.pm;h=50de1bed22d71ba4ac72cc3a6f781368907881c3;hb=7349713101700e488231ad9ffece8ee42de0928c;hp=6b7b3c7a71bfcb9ccb521a47f41b3cd30d4bab07;hpb=bf8df8160076d7a1231e0858ca4c243df3b7c860;p=public-inbox.git

diff --git a/lib/PublicInbox/IPC.pm b/lib/PublicInbox/IPC.pm
index 6b7b3c7a..50de1bed 100644
--- a/lib/PublicInbox/IPC.pm
+++ b/lib/PublicInbox/IPC.pm
@@ -1,14 +1,26 @@
 # Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 
-# base class for remote IPC calls, requires Storable
-# TODO: this ought to be usable in SearchIdxShard
+# base class for remote IPC calls and workqueues, requires Storable or Sereal
+# - ipc_do and ipc_worker_* is for a single worker/producer and uses pipes
+# - wq_do and wq_worker* is for a single producer and multiple workers,
+#   using SOCK_SEQPACKET for work distribution
+# use ipc_do when you need work done on a certain process
+# use wq_do when your work can be done on any idle worker
 package PublicInbox::IPC;
 use strict;
 use v5.10.1;
-use Socket qw(AF_UNIX SOCK_STREAM);
+use parent qw(Exporter);
 use Carp qw(confess croak);
-use PublicInbox::Sigfd;
+use PublicInbox::DS qw(dwaitpid);
+use PublicInbox::Spawn;
+use PublicInbox::OnDestroy;
+use PublicInbox::WQWorker;
+use Socket qw(AF_UNIX MSG_EOR SOCK_STREAM);
+my $SEQPACKET = eval { Socket::SOCK_SEQPACKET() }; # portable enough?
+use constant PIPE_BUF => $^O eq 'linux' ? 4096 : POSIX::_POSIX_PIPE_BUF();
+our @EXPORT_OK = qw(ipc_freeze ipc_thaw);
+my $WQ_MAX_WORKERS = 4096;
 my ($enc, $dec);
 # ->imports at BEGIN turns sereal_*_with_object into custom ops on 5.14+
 # and eliminate method call overhead
@@ -23,50 +35,66 @@ BEGIN {
 };
 
 if ($enc && $dec) { # should be custom ops
-	*freeze = sub ($) { sereal_encode_with_object $enc, $_[0] };
-	*thaw = sub ($) { sereal_decode_with_object $dec, $_[0], my $ret };
+	*ipc_freeze = sub ($) { sereal_encode_with_object $enc, $_[0] };
+	*ipc_thaw = sub ($) { sereal_decode_with_object $dec, $_[0], my $ret };
 } else {
 	eval { # some distros have Storable as a separate package from Perl
 		require Storable;
-		Storable->import(qw(freeze thaw));
+		*ipc_freeze = \&Storable::freeze;
+		*ipc_thaw = \&Storable::thaw;
 		$enc = 1;
 	} // warn("Storable (part of Perl) missing: $@\n");
 }
 
+my $recv_cmd = PublicInbox::Spawn->can('recv_cmd4');
+my $send_cmd = PublicInbox::Spawn->can('send_cmd4') // do {
+	require PublicInbox::CmdIPC4;
+	$recv_cmd //= PublicInbox::CmdIPC4->can('recv_cmd4');
+	PublicInbox::CmdIPC4->can('send_cmd4');
+};
+
 sub _get_rec ($) {
-	my ($sock) = @_;
-	local $/ = "\n";
-	defined(my $len = <$sock>) or return;
+	my ($r) = @_;
+	defined(my $len = <$r>) or return;
 	chop($len) eq "\n" or croak "no LF byte in $len";
-	defined(my $r = read($sock, my $buf, $len)) or croak "read error: $!";
-	$r == $len or croak "short read: $r != $len";
-	thaw($buf);
+	defined(my $n = read($r, my $buf, $len)) or croak "read error: $!";
+	$n == $len or croak "short read: $n != $len";
+	ipc_thaw($buf);
+}
+
+sub _pack_rec ($) {
+	my ($ref) = @_;
+	my $buf = ipc_freeze($ref);
+	length($buf) . "\n" . $buf;
 }
 
 sub _send_rec ($$) {
-	my ($sock, $ref) = @_;
-	my $buf = freeze($ref);
-	print $sock length($buf), "\n", $buf or croak "print: $!";
+	my ($w, $ref) = @_;
+	print $w _pack_rec($ref) or croak "print: $!";
 }
 
 sub ipc_return ($$$) {
-	my ($s2, $ret, $exc) = @_;
-	_send_rec($s2, $exc ? bless(\$exc, 'PublicInbox::IPC::Die') : $ret);
+	my ($w, $ret, $exc) = @_;
+	_send_rec($w, $exc ? bless(\$exc, 'PublicInbox::IPC::Die') : $ret);
 }
 
-sub ipc_worker_loop ($$) {
-	my ($self, $s2) = @_;
-	while (my $rec = _get_rec($s2)) {
-		my ($wantarray, $sub, @args) = @$rec;
-		if (!defined($wantarray)) { # no waiting if client doesn't care
+sub ipc_worker_loop ($$$) {
+	my ($self, $r_req, $w_res) = @_;
+	my ($rec, $wantarray, $sub, @args);
+	local $/ = "\n";
+	while ($rec = _get_rec($r_req)) {
+		($wantarray, $sub, @args) = @$rec;
+		# no waiting if client doesn't care,
+		# this is the overwhelmingly likely case
+		if (!defined($wantarray)) {
 			eval { $self->$sub(@args) };
-			eval { warn "die: $@ (from nowait $sub)\n" } if $@;
+			warn "$$ die: $@ (from nowait $sub)\n" if $@;
 		} elsif ($wantarray) {
 			my @ret = eval { $self->$sub(@args) };
-			ipc_return($s2, \@ret, $@);
-		} else {
+			ipc_return($w_res, \@ret, $@);
+		} else { # '' => wantscalar
 			my $ret = eval { $self->$sub(@args) };
-			ipc_return($s2, \$ret, $@);
+			ipc_return($w_res, \$ret, $@);
 		}
 	}
 }
@@ -75,71 +103,82 @@ sub ipc_worker_loop ($$) {
 sub ipc_worker_spawn {
 	my ($self, $ident, $oldset) = @_;
 	return unless $enc; # no Sereal or Storable
-	my $pid = $self->{-ipc_worker_pid};
-	confess "BUG: already spawned PID:$pid" if $pid;
-	confess "BUG: already have worker socket" if $self->{-ipc_sock};
-	my ($s1, $s2);
-	socketpair($s1, $s2, AF_UNIX, SOCK_STREAM, 0) or die "socketpair: $!";
-	my $sigset = $oldset // PublicInbox::Sigfd::block_signals();
-	my $parent = $$;
-	$self->ipc_atfork_parent;
-	defined($pid = fork) or die "fork: $!";
+	return if ($self->{-ipc_ppid} // -1) == $$; # idempotent
+	delete(@$self{qw(-ipc_req -ipc_res -ipc_ppid -ipc_pid)});
+	pipe(my ($r_req, $w_req)) or die "pipe: $!";
+	pipe(my ($r_res, $w_res)) or die "pipe: $!";
+	my $sigset = $oldset // PublicInbox::DS::block_signals();
+	$self->ipc_atfork_prepare;
+	my $seed = rand(0xffffffff);
+	my $pid = fork // die "fork: $!";
 	if ($pid == 0) {
+		srand($seed);
 		eval { PublicInbox::DS->Reset };
-		$self->{-ipc_parent_pid} = $parent;
-		close $s1 or die "close(\$s1): $!";
-		$s2->autoflush(1);
+		delete @$self{qw(-wq_s1 -wq_s2 -wq_workers -wq_ppid)};
+		$w_req = $r_res = undef;
+		$w_res->autoflush(1);
 		$SIG{$_} = 'IGNORE' for (qw(TERM INT QUIT));
 		local $0 = $ident;
-		PublicInbox::Sigfd::sig_setmask($oldset);
-		my $on_destroy = $self->ipc_atfork_child;
-		eval { ipc_worker_loop($self, $s2) };
+		PublicInbox::DS::sig_setmask($sigset);
+		# ensure we properly exit even if warn() dies:
+		my $end = PublicInbox::OnDestroy->new($$, sub { exit(!!$@) });
+		eval {
+			my $on_destroy = $self->ipc_atfork_child;
+			local %SIG = %SIG;
+			ipc_worker_loop($self, $r_req, $w_res);
+		};
 		die "worker $ident PID:$$ died: $@\n" if $@;
-		exit;
+		undef $end; # trigger exit
 	}
-	PublicInbox::Sigfd::sig_setmask($sigset) unless $oldset;
-	close $s2 or die "close(\$s2): $!";
-	$s1->autoflush(1);
-	$self->{-ipc_sock} = $s1;
-	$self->{-ipc_worker_pid} = $pid;
+	PublicInbox::DS::sig_setmask($sigset) unless $oldset;
+	$r_req = $w_res = undef;
+	$w_req->autoflush(1);
+	$self->{-ipc_req} = $w_req;
+	$self->{-ipc_res} = $r_res;
+	$self->{-ipc_ppid} = $$;
+	$self->{-ipc_pid} = $pid;
 }
 
 sub ipc_worker_reap { # dwaitpid callback
-	my ($self, $pid) = @_;
-	warn "PID:$pid died with \$?=$?\n" if $?;
+	my ($args, $pid) = @_;
+	return if !$?;
+	# TERM(15) is our default exit signal, PIPE(13) is likely w/ pager
+	my $s = $? & 127;
+	warn "PID:$pid died with \$?=$?\n" if $s != 15 && $s != 13;
+}
+
+sub wq_wait_old {
+	my ($self, $args) = @_;
+	my $pids = delete $self->{"-wq_old_pids.$$"} or return;
+	dwaitpid($_, \&ipc_worker_reap, [$self, $args]) for @$pids;
 }
 
 # for base class, override in sub classes
-sub ipc_atfork_parent {}
-sub ipc_atfork_child {}
+sub ipc_atfork_prepare {}
 
-# should only be called inside the worker process
-sub ipc_worker_exit {
-	my (undef, $code) = @_;
-	exit($code);
+sub wq_atexit_child {}
+
+sub ipc_atfork_child {
+	my ($self) = @_;
+	my $io = delete($self->{-ipc_atfork_child_close}) or return;
+	close($_) for @$io;
+	undef;
 }
 
 # idempotent, can be called regardless of whether worker is active or not
 sub ipc_worker_stop {
-	my ($self) = @_;
-	my $pid;
-	my $s1 = delete $self->{-ipc_sock} or do {
-		$pid = delete $self->{-ipc_worker_pid} and
-			die "unexpected PID:$pid without ipc_sock";
-		return;
-	};
-	$pid = delete $self->{-ipc_worker_pid} or die "no PID?";
-	_send_rec($s1, [ undef, 'ipc_worker_exit', 0 ]);
-	shutdown($s1, 2) or die "shutdown(\$s1) for PID:$pid";
-	eval {
-		my $reap = $self->can('ipc_worker_reap');
-		PublicInbox::DS::dwaitpid($pid, $reap, $self);
-	};
-	if ($@) {
-		my $wp = waitpid($pid, 0);
-		$pid == $wp or die "waitpid($pid) returned $wp: \$?=$?";
-		$self->ipc_worker_reap($pid);
+	my ($self, $args) = @_;
+	my ($pid, $ppid) = delete(@$self{qw(-ipc_pid -ipc_ppid)});
+	my ($w_req, $r_res) = delete(@$self{qw(-ipc_req -ipc_res)});
+	if (!$w_req && !$r_res) {
+		die "unexpected PID:$pid without IPC pipes" if $pid;
+		return; # idempotent
 	}
+	die 'no PID with IPC pipes' unless $pid;
+	$w_req = $r_res = undef;
+
+	return if $$ != $ppid;
+	dwaitpid($pid, \&ipc_worker_reap, [$self, $args]);
 }
 
 # use this if we have multiple readers reading curl or "pigz -dc"
@@ -150,20 +189,281 @@ sub ipc_lock_init {
 	$self->{-ipc_lock} //= bless { lock_path => $f }, 'PublicInbox::Lock'
 }
 
+sub ipc_async_wait ($$) {
+	my ($self, $max) = @_; # max == -1 to wait for all
+	my $aif = $self->{-async_inflight} or return;
+	my $r_res = $self->{-ipc_res} or die 'BUG: no ipc_res';
+	while (my ($sub, $bytes, $cb, $cb_arg) = splice(@$aif, 0, 4)) {
+		my $ret = _get_rec($r_res) //
+			die "no response on $sub (req.size=$bytes)";
+		$self->{-async_inflight_bytes} -= $bytes;
+
+		eval { $cb->($cb_arg, $ret) };
+		warn "E: $sub callback error: $@\n" if $@;
+		return if --$max == 0;
+	}
+}
+
 # call $self->$sub(@args), on a worker if ipc_worker_spawn was used
 sub ipc_do {
 	my ($self, $sub, @args) = @_;
-	if (my $s1 = $self->{-ipc_sock}) {
+	if (my $w_req = $self->{-ipc_req}) { # run in worker
 		my $ipc_lock = $self->{-ipc_lock};
 		my $lock = $ipc_lock ? $ipc_lock->lock_for_scope : undef;
-		_send_rec($s1, [ wantarray, $sub, @args ]);
-		return unless defined(wantarray);
-		my $ret = _get_rec($s1) // die "no response on $sub";
-		die $$ret if ref($ret) eq 'PublicInbox::IPC::Die';
-		wantarray ? @$ret : $$ret;
-	} else {
+		if (defined(wantarray)) {
+			my $r_res = $self->{-ipc_res} or die 'BUG: no ipc_res';
+			ipc_async_wait($self, -1);
+			_send_rec($w_req, [ wantarray, $sub, @args ]);
+			my $ret = _get_rec($r_res) // die "no response on $sub";
+			die $$ret if ref($ret) eq 'PublicInbox::IPC::Die';
+			wantarray ? @$ret : $$ret;
+		} else { # likely, fire-and-forget into pipe
+			_send_rec($w_req, [ undef , $sub, @args ]);
+		}
+	} else { # run locally
 		$self->$sub(@args);
 	}
 }
 
+sub ipc_async {
+	my ($self, $sub, $sub_args, $cb, $cb_arg) = @_;
+	if (my $w_req = $self->{-ipc_req}) { # run in worker
+		my $rec = _pack_rec([ 1, $sub, @$sub_args ]);
+		my $cur_bytes = \($self->{-async_inflight_bytes} //= 0);
+		while (($$cur_bytes + length($rec)) > PIPE_BUF) {
+			ipc_async_wait($self, 1);
+		}
+		my $ipc_lock = $self->{-ipc_lock};
+		my $lock = $ipc_lock ? $ipc_lock->lock_for_scope : undef;
+		print $w_req $rec or croak "print: $!";
+		$$cur_bytes += length($rec);
+		push @{$self->{-async_inflight}},
+				$sub, length($rec), $cb, $cb_arg;
+	} else {
+		my $ret = [ eval { $self->$sub(@$sub_args) } ];
+		if (my $exc = $@) {
+			$ret = ( bless(\$exc, 'PublicInbox::IPC::Die') );
+		}
+		eval { $cb->($cb_arg, $ret) };
+		warn "E: $sub callback error: $@\n" if $@;
+	}
+}
+
+# needed when there's multiple IPC workers and the parent forking
+# causes newer siblings to inherit older siblings sockets
+sub ipc_sibling_atfork_child {
+	my ($self) = @_;
+	my ($pid, undef) = delete(@$self{qw(-ipc_pid -ipc_ppid)});
+	delete(@$self{qw(-ipc_req -ipc_res)});
+	$pid == $$ and die "BUG: $$ ipc_atfork_child called on itself";
+}
+
+sub recv_and_run {
+	my ($self, $s2, $len, $full_stream) = @_;
+	my @fds = $recv_cmd->($s2, my $buf, $len);
+	return if scalar(@fds) && !defined($fds[0]);
+	my $n = length($buf) or return 0;
+	my $nfd = 0;
+	for my $fd (@fds) {
+		if (open(my $cmdfh, '+<&=', $fd)) {
+			$self->{$nfd++} = $cmdfh;
+			$cmdfh->autoflush(1);
+		} else {
+			die "$$ open(+<&=$fd) (FD:$nfd): $!";
+		}
+	}
+	while ($full_stream && $n < $len) {
+		my $r = sysread($s2, $buf, $len - $n, $n) // croak "read: $!";
+		croak "read EOF after $n/$len bytes" if $r == 0;
+		$n = length($buf);
+	}
+	# Sereal dies on truncated data, Storable returns undef
+	my $args = ipc_thaw($buf) // die "thaw error on buffer of size: $n";
+	undef $buf;
+	my $sub = shift @$args;
+	eval { $self->$sub(@$args) };
+	warn "$$ wq_worker: $@" if $@;
+	delete @$self{0..($nfd-1)};
+	$n;
+}
+
+sub wq_worker_loop ($) {
+	my ($self) = @_;
+	my $wqw = PublicInbox::WQWorker->new($self);
+	PublicInbox::DS->SetPostLoopCallback(sub { $wqw->{sock} });
+	PublicInbox::DS->EventLoop;
+	PublicInbox::DS->Reset;
+}
+
+sub do_sock_stream { # via wq_do, for big requests
+	my ($self, $len) = @_;
+	recv_and_run($self, delete $self->{0}, $len, 1);
+}
+
+sub wq_do { # always async
+	my ($self, $sub, $ios, @args) = @_;
+	if (my $s1 = $self->{-wq_s1}) { # run in worker
+		my $fds = [ map { fileno($_) } @$ios ];
+		my $buf = ipc_freeze([$sub, @args]);
+		my $n = $send_cmd->($s1, $fds, $buf, MSG_EOR);
+		return if defined($n); # likely
+		croak "sendmsg: $! (check RLIMIT_NOFILE)" if $!{ETOOMANYREFS};
+		croak "sendmsg: $!" if !$!{EMSGSIZE};
+		socketpair(my $r, my $w, AF_UNIX, SOCK_STREAM, 0) or
+			croak "socketpair: $!";
+		$n = $send_cmd->($s1, [ fileno($r) ],
+				ipc_freeze(['do_sock_stream', length($buf)]),
+				MSG_EOR) // croak "sendmsg: $!";
+		undef $r;
+		$n = $send_cmd->($w, $fds, $buf, 0) // croak "sendmsg: $!";
+		while ($n < length($buf)) {
+			my $x = syswrite($w, $buf, length($buf) - $n, $n) //
+					croak "syswrite: $!";
+			croak "syswrite wrote 0 bytes" if $x == 0;
+			$n += $x;
+		}
+	} else {
+		@$self{0..$#$ios} = @$ios;
+		eval { $self->$sub(@args) };
+		warn "wq_do: $@" if $@;
+		delete @$self{0..$#$ios}; # don't close
+	}
+}
+
+sub _wq_worker_start ($$$) {
+	my ($self, $oldset, $fields) = @_;
+	my $seed = rand(0xffffffff);
+	my $pid = fork // die "fork: $!";
+	if ($pid == 0) {
+		srand($seed);
+		eval { PublicInbox::DS->Reset };
+		delete @$self{qw(-wq_s1 -wq_workers -wq_ppid)};
+		@$self{keys %$fields} = values(%$fields) if $fields;
+		$SIG{$_} = 'IGNORE' for (qw(PIPE));
+		$SIG{$_} = 'DEFAULT' for (qw(TTOU TTIN TERM QUIT INT CHLD));
+		local $0 = $self->{-wq_ident};
+		PublicInbox::DS::sig_setmask($oldset);
+		# ensure we properly exit even if warn() dies:
+		my $end = PublicInbox::OnDestroy->new($$, sub { exit(!!$@) });
+		eval {
+			my $on_destroy = $self->ipc_atfork_child;
+			local %SIG = %SIG;
+			wq_worker_loop($self);
+		};
+		warn "worker $self->{-wq_ident} PID:$$ died: $@" if $@;
+		undef $end; # trigger exit
+	} else {
+		$self->{-wq_workers}->{$pid} = \undef;
+	}
+}
+
+# starts workqueue workers if Sereal or Storable is installed
+sub wq_workers_start {
+	my ($self, $ident, $nr_workers, $oldset, $fields) = @_;
+	($enc && $send_cmd && $recv_cmd && defined($SEQPACKET)) or return;
+	return if $self->{-wq_s1}; # idempotent
+	$self->{-wq_s1} = $self->{-wq_s2} = undef;
+	socketpair($self->{-wq_s1}, $self->{-wq_s2}, AF_UNIX, $SEQPACKET, 0) or
+		die "socketpair: $!";
+	$self->ipc_atfork_prepare;
+	$nr_workers //= 4;
+	$nr_workers = $WQ_MAX_WORKERS if $nr_workers > $WQ_MAX_WORKERS;
+	my $sigset = $oldset // PublicInbox::DS::block_signals();
+	$self->{-wq_workers} = {};
+	$self->{-wq_ident} = $ident;
+	_wq_worker_start($self, $sigset, $fields) for (1..$nr_workers);
+	PublicInbox::DS::sig_setmask($sigset) unless $oldset;
+	$self->{-wq_ppid} = $$;
+}
+
+sub wq_worker_incr { # SIGTTIN handler
+	my ($self, $oldset, $fields) = @_;
+	$self->{-wq_s2} or return;
+	return if wq_workers($self) >= $WQ_MAX_WORKERS;
+	$self->ipc_atfork_prepare;
+	my $sigset = $oldset // PublicInbox::DS::block_signals();
+	_wq_worker_start($self, $sigset, $fields);
+	PublicInbox::DS::sig_setmask($sigset) unless $oldset;
+}
+
+sub wq_exit { # wakes up wq_worker_decr_wait
+	send($_[0]->{-wq_s2}, $$, MSG_EOR) // die "$$ send: $!";
+	exit;
+}
+
+sub wq_worker_decr { # SIGTTOU handler, kills first idle worker
+	my ($self) = @_;
+	return unless wq_workers($self);
+	my $s2 = $self->{-wq_s2} // die 'BUG: no wq_s2';
+	$self->wq_do('wq_exit', [ $s2, $s2, $s2 ]);
+	# caller must call wq_worker_decr_wait in main loop
+}
+
+sub wq_worker_decr_wait {
+	my ($self, $timeout) = @_;
+	return if $self->{-wq_ppid} != $$; # can't reap siblings or parents
+	my $s1 = $self->{-wq_s1} // croak 'BUG: no wq_s1';
+	vec(my $rin = '', fileno($s1), 1) = 1;
+	select(my $rout = $rin, undef, undef, $timeout) or
+		croak 'timed out waiting for wq_exit';
+	recv($s1, my $pid, 64, 0) // croak "recv: $!";
+	my $workers = $self->{-wq_workers} // croak 'BUG: no wq_workers';
+	delete $workers->{$pid} // croak "BUG: PID:$pid invalid";
+	dwaitpid($pid, \&ipc_worker_reap, $self);
+}
+
+# set or retrieve number of workers
+sub wq_workers {
+	my ($self, $nr) = @_;
+	my $cur = $self->{-wq_workers} or return;
+	if (defined $nr) {
+		while (scalar(keys(%$cur)) > $nr) {
+			$self->wq_worker_decr;
+			$self->wq_worker_decr_wait;
+		}
+		$self->wq_worker_incr while scalar(keys(%$cur)) < $nr;
+	}
+	scalar(keys(%$cur));
+}
+
+sub wq_close {
+	my ($self, $nohang) = @_;
+	delete @$self{qw(-wq_s1 -wq_s2)} or return;
+	my $ppid = delete $self->{-wq_ppid} or return;
+	my $workers = delete $self->{-wq_workers} // die 'BUG: no wq_workers';
+	return if $ppid != $$; # can't reap siblings or parents
+	my @pids = map { $_ + 0 } keys %$workers;
+	if ($nohang) {
+		push @{$self->{"-wq_old_pids.$$"}}, @pids;
+	} else {
+		dwaitpid($_, \&ipc_worker_reap, $self) for @pids;
+	}
+}
+
+sub wq_kill_old {
+	my ($self) = @_;
+	my $pids = $self->{"-wq_old_pids.$$"} or return;
+	kill 'TERM', @$pids;
+}
+
+sub wq_kill {
+	my ($self, $sig) = @_;
+	my $workers = $self->{-wq_workers} or return;
+	kill($sig // 'TERM', keys %$workers);
+}
+
+sub WQ_MAX_WORKERS { $WQ_MAX_WORKERS }
+
+sub DESTROY {
+	my ($self) = @_;
+	my $ppid = $self->{-wq_ppid};
+	wq_kill($self) if $ppid && $ppid == $$;
+	wq_close($self);
+	wq_wait_old($self);
+	ipc_worker_stop($self);
+}
+
+# Sereal doesn't have dclone
+sub deep_clone { ipc_thaw(ipc_freeze($_[-1])) }
+
 1;