use Carp qw(confess croak);
use PublicInbox::DS qw(dwaitpid);
use PublicInbox::Spawn;
-use POSIX ();
+use POSIX qw(WNOHANG);
use Socket qw(AF_UNIX MSG_EOR);
my $SEQPACKET = eval { Socket::SOCK_SEQPACKET() }; # portable enough?
use constant PIPE_BUF => $^O eq 'linux' ? 4096 : POSIX::_POSIX_PIPE_BUF();
+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
require PublicInbox::CmdIPC4;
$recv_cmd //= PublicInbox::CmdIPC4->can('recv_cmd4');
PublicInbox::CmdIPC4->can('send_cmd4');
-} // do {
- require PublicInbox::CmdIPC1;
- $recv_cmd = PublicInbox::CmdIPC1->can('recv_cmd1');
- PublicInbox::CmdIPC1->can('send_cmd1');
};
+sub wq_set_recv_modes {
+ my ($self, @modes) = @_;
+ $self->{-wq_recv_modes} = \@modes;
+}
+
sub _get_rec ($) {
my ($r) = @_;
defined(my $len = <$r>) or return;
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();
- my $parent = $$;
- $self->ipc_atfork_parent;
+ $self->ipc_atfork_prepare;
defined(my $pid = fork) or die "fork: $!";
if ($pid == 0) {
eval { PublicInbox::DS->Reset };
- $self->{-ipc_parent_pid} = $parent;
+ delete @$self{qw(-wq_s1 -wq_workers -wq_ppid)};
$w_req = $r_res = undef;
$w_res->autoflush(1);
$SIG{$_} = 'IGNORE' for (qw(TERM INT QUIT));
local $0 = $ident;
- PublicInbox::DS::sig_setmask($oldset);
+ PublicInbox::DS::sig_setmask($sigset);
my $on_destroy = $self->ipc_atfork_child;
eval { ipc_worker_loop($self, $r_req, $w_res) };
die "worker $ident PID:$$ died: $@\n" if $@;
sub ipc_worker_reap { # dwaitpid callback
my ($self, $pid) = @_;
- warn "PID:$pid died with \$?=$?\n" if $?;
+ # SIGTERM (15) is our default exit signal
+ warn "PID:$pid died with \$?=$?\n" if $? && ($? & 127) != 15;
}
# 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 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
return; # idempotent
}
die 'no PID with IPC pipes' unless $pid;
- _send_rec($w_req, [ undef, 'ipc_worker_exit', 0 ]);
$w_req = $r_res = undef;
- # allow any sibling to send ipc_worker_exit, but siblings can't wait
return if $$ != $ppid;
dwaitpid($pid, \&ipc_worker_reap, $self);
}
$pid == $$ and die "BUG: $$ ipc_atfork_child called on itself";
}
-sub wq_worker_loop ($$) {
- my ($self, $s2) = @_;
- my $buf;
+sub wq_worker_loop ($) {
+ my ($self) = @_;
my $len = $self->{wq_req_len} // (4096 * 33);
- my ($rec, $sub, @args);
+ my $s2 = $self->{-wq_s2} // die 'BUG: no -wq_s2';
while (1) {
- my (@fds) = $recv_cmd->($s2, $buf, $len) or return; # EOF
- my $i = 0;
- my @m = @{$self->{wq_open_modes} // [qw( +<&= >&= >&= )]};
+ my @fds = $recv_cmd->($s2, my $buf, $len) or return; # EOF
+ my @m = @{$self->{-wq_recv_modes} // [qw( +<&= >&= >&= )]};
+ my $nfd = 0;
for my $fd (@fds) {
my $mode = shift(@m);
- if (open(my $fh, $mode, $fd)) {
- $self->{$i++} = $fh;
+ if (open(my $cmdfh, $mode, $fd)) {
+ $self->{$nfd++} = $cmdfh;
+ $cmdfh->autoflush(1);
} else {
- die "$$ open($mode$fd) (FD:$i): $!";
+ die "$$ open($mode$fd) (FD:$nfd): $!";
}
}
- # Sereal dies, Storable returns undef
- $rec = thaw($buf) //
+ # Sereal dies on truncated data, Storable returns undef
+ my $args = thaw($buf) //
die "thaw error on buffer of size:".length($buf);
- ($sub, @args) = @$rec;
- eval { $self->$sub(@args) };
- warn "$$ wq_worker: $@" if $@;
- delete @$self{0, 1, 2};
+ my $sub = shift @$args;
+ eval { $self->$sub(@$args) };
+ warn "$$ wq_worker: $@" if $@ &&
+ ref($@) ne 'PublicInbox::SIGPIPE';
+ delete @$self{0..($nfd-1)};
}
}
sub wq_do { # always async
- my ($self, $sub, $in, $out, $err, @args) = @_;
- if (my $s1 = $self->{-wq_seq}) { # run in worker
- $_ = fileno($_) for ($in, $out, $err);
- $send_cmd->($s1, $in, $out, $err,
- freeze([$sub, @args]), MSG_EOR);
+ my ($self, $sub, $ios, @args) = @_;
+ if (my $s1 = $self->{-wq_s1}) { # run in worker
+ my $fds = [ map { fileno($_) } @$ios ];
+ $send_cmd->($s1, $fds, freeze([$sub, @args]), MSG_EOR);
} else {
- @$self{0, 1, 2} = ($in, $out, $err);
+ @$self{0..$#$ios} = @$ios;
eval { $self->$sub(@args) };
- warn "wq_do: $@" if $@;
- delete @$self{0, 1, 2};
+ warn "wq_do: $@" if $@ && ref($@) ne 'PublicInbox::SIGPIPE';
+ delete @$self{0..$#$ios}; # don't close
+ }
+}
+
+sub _wq_worker_start ($$) {
+ my ($self, $oldset) = @_;
+ my $pid = fork // die "fork: $!";
+ if ($pid == 0) {
+ eval { PublicInbox::DS->Reset };
+ delete @$self{qw(-wq_s1 -wq_workers -wq_ppid)};
+ $SIG{$_} = 'IGNORE' for (qw(PIPE TTOU TTIN));
+ $SIG{$_} = 'DEFAULT' for (qw(TERM QUIT INT CHLD));
+ local $0 = $self->{-wq_ident};
+ PublicInbox::DS::sig_setmask($oldset);
+ # ensure we properly exit even if warn() dies:
+ my $end = PublicInbox::OnDestroy->new($$, sub { exit(!!$@) });
+ my $on_destroy = $self->ipc_atfork_child;
+ eval { wq_worker_loop($self) };
+ warn "worker $self->{-wq_ident} PID:$$ died: $@" if $@;
+ undef $on_destroy;
+ undef $end; # trigger exit
+ } else {
+ $self->{-wq_workers}->{$pid} = \undef;
}
}
sub wq_workers_start {
my ($self, $ident, $nr_workers, $oldset) = @_;
($enc && $send_cmd && $recv_cmd && defined($SEQPACKET)) or return;
- return if $self->{-wq_seq}; # idempotent
- my ($s1, $s2);
- socketpair($s1, $s2, AF_UNIX, $SEQPACKET, 0) or die "socketpair: $!";
- my $sigset = $oldset // PublicInbox::DS::block_signals();
- $self->ipc_atfork_parent;
+ return if $self->{-wq_s1}; # idempotent
+ $self->{-wq_s1} = $self->{-wq_s2} = undef;
+ socketpair($self->{-wq_s1}, $self->{-wq_s2}, AF_UNIX, $SEQPACKET, 0) or
+ die "socketpair: $!";
+ $self->ipc_atfork_prepare;
$nr_workers //= 4;
+ $nr_workers = $WQ_MAX_WORKERS if $nr_workers > $WQ_MAX_WORKERS;
+ my $sigset = $oldset // PublicInbox::DS::block_signals();
$self->{-wq_workers} = {};
- for my $i (0..($nr_workers - 1)) {
- defined(my $pid = fork) or die "fork: $!";
- if ($pid == 0) {
- eval { PublicInbox::DS->Reset };
- $s1 = undef;
- $SIG{$_} = 'IGNORE' for (qw(TERM INT QUIT));
- local $0 = $ident."[$i]";
- PublicInbox::DS::sig_setmask($oldset);
- my $on_destroy = $self->ipc_atfork_child;
- eval { wq_worker_loop($self, $s2) };
- die "worker $ident PID:$$ died: $@\n" if $@;
- exit;
- } else {
- $self->{-wq_workers}->{$pid} = $i;
- }
- }
+ $self->{-wq_ident} = $ident;
+ _wq_worker_start($self, $sigset) for (1..$nr_workers);
PublicInbox::DS::sig_setmask($sigset) unless $oldset;
- $s2 = undef;
- $self->{-wq_seq} = $s1;
$self->{-wq_ppid} = $$;
}
+sub wq_worker_incr { # SIGTTIN handler
+ my ($self, $oldset) = @_;
+ $self->{-wq_s2} or return;
+ return if wq_workers($self) >= $WQ_MAX_WORKERS;
+ $self->ipc_atfork_prepare;
+ my $sigset = $oldset // PublicInbox::DS::block_signals();
+ _wq_worker_start($self, $sigset);
+ PublicInbox::DS::sig_setmask($sigset) unless $oldset;
+}
+
+sub wq_exit { # wakes up wq_worker_decr_wait
+ send($_[0]->{-wq_s2}, $$, 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) = @_;
- delete $self->{-wq_seq} or return;
- my $ppid = delete $self->{-wq_ppid} // die 'BUG: no wq_ppid';
+ delete @$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 != $$; # can't reap siblings or parents
+ return (keys %$workers) if wantarray; # caller will reap
for my $pid (keys %$workers) {
dwaitpid($pid, \&ipc_worker_reap, $self);
}
}
+sub wq_kill {
+ my ($self, $sig) = @_;
+ my $workers = $self->{-wq_workers} or return;
+ kill($sig // 'TERM', keys %$workers);
+}
+
+sub WQ_MAX_WORKERS { $WQ_MAX_WORKERS }
+
+sub DESTROY {
+ my ($self) = @_;
+ my $ppid = $self->{-wq_ppid};
+ wq_kill($self) if $ppid && $ppid == $$;
+ wq_close($self);
+ ipc_worker_stop($self);
+}
+
+# Sereal doesn't have dclone
+sub deep_clone { thaw(freeze($_[-1])) }
+
1;