-# Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
+# Copyright (C) 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_io_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_io_do when your work can be done on any idle worker
package PublicInbox::IPC;
use strict;
use v5.10.1;
-use Carp qw(confess croak);
-use PublicInbox::Sigfd;
+use parent qw(Exporter);
+use Carp qw(croak);
+use PublicInbox::DS qw(awaitpid);
+use PublicInbox::Spawn;
+use PublicInbox::OnDestroy;
+use PublicInbox::WQWorker;
+use Socket qw(AF_UNIX MSG_EOR SOCK_STREAM);
+my $MY_MAX_ARG_STRLEN = 4096 * 33; # extra 4K for serialization
+my $SEQPACKET = eval { Socket::SOCK_SEQPACKET() }; # portable enough?
+our @EXPORT_OK = qw(ipc_freeze ipc_thaw);
my ($enc, $dec);
# ->imports at BEGIN turns sereal_*_with_object into custom ops on 5.14+
# and eliminate method call overhead
};
if ($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));
- $enc = 1;
- } // warn("Storable (part of Perl) missing: $@\n");
+ require Storable;
+ *ipc_freeze = \&Storable::freeze;
+ *ipc_thaw = \&Storable::thaw;
}
+my $recv_cmd = PublicInbox::Spawn->can('recv_cmd4');
+our $send_cmd = PublicInbox::Spawn->can('send_cmd4') // do {
+ require PublicInbox::CmdIPC4;
+ $recv_cmd //= PublicInbox::CmdIPC4->can('recv_cmd4');
+ PublicInbox::CmdIPC4->can('send_cmd4');
+} // do {
+ require PublicInbox::Syscall;
+ $recv_cmd //= PublicInbox::Syscall->can('recv_cmd4');
+ PublicInbox::Syscall->can('send_cmd4');
+};
+
sub _get_rec ($) {
my ($r) = @_;
defined(my $len = <$r>) or return;
chop($len) eq "\n" or croak "no LF byte in $len";
defined(my $n = read($r, my $buf, $len)) or croak "read error: $!";
$n == $len or croak "short read: $n != $len";
- thaw($buf);
+ ipc_thaw($buf);
}
sub _send_rec ($$) {
my ($w, $ref) = @_;
- my $buf = freeze($ref);
+ my $buf = ipc_freeze($ref);
print $w length($buf), "\n", $buf or croak "print: $!";
}
# this is the overwhelmingly likely case
if (!defined($wantarray)) {
eval { $self->$sub(@args) };
- eval { warn "$$ die: $@ (from nowait $sub)\n" } if $@;
+ warn "$$ die: $@ (from nowait $sub)\n" if $@;
} elsif ($wantarray) {
my @ret = eval { $self->$sub(@args) };
ipc_return($w_res, \@ret, $@);
# starts a worker if Sereal or Storable is installed
sub ipc_worker_spawn {
- my ($self, $ident, $oldset) = @_;
- return unless $enc; # no Sereal or Storable
+ my ($self, $ident, $oldset, $fields) = @_;
return if ($self->{-ipc_ppid} // -1) == $$; # 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::Sigfd::block_signals();
- my $parent = $$;
- $self->ipc_atfork_parent;
- defined(my $pid = fork) or die "fork: $!";
+ my $sigset = $oldset // PublicInbox::DS::block_signals();
+ $self->ipc_atfork_prepare;
+ my $seed = rand(0xffffffff);
+ my $pid = fork // die "fork: $!";
if ($pid == 0) {
+ srand($seed);
+ eval { Net::SSLeay::randomize() };
eval { PublicInbox::DS->Reset };
- $self->{-ipc_parent_pid} = $parent;
+ delete @$self{qw(-wq_s1 -wq_s2 -wq_workers -wq_ppid)};
$w_req = $r_res = undef;
$w_res->autoflush(1);
$SIG{$_} = 'IGNORE' for (qw(TERM INT QUIT));
local $0 = $ident;
- PublicInbox::Sigfd::sig_setmask($oldset);
- my $on_destroy = $self->ipc_atfork_child;
- eval { ipc_worker_loop($self, $r_req, $w_res) };
- die "worker $ident PID:$$ died: $@\n" if $@;
- exit;
+ # ensure we properly exit even if warn() dies:
+ my $end = PublicInbox::OnDestroy->new($$, sub { exit(!!$@) });
+ eval {
+ $fields //= {};
+ local @$self{keys %$fields} = values(%$fields);
+ my $on_destroy = $self->ipc_atfork_child;
+ local @SIG{keys %SIG} = values %SIG;
+ PublicInbox::DS::sig_setmask($sigset);
+ ipc_worker_loop($self, $r_req, $w_res);
+ };
+ warn "worker $ident PID:$$ died: $@\n" if $@;
+ undef $end; # trigger exit
}
- PublicInbox::Sigfd::sig_setmask($sigset) unless $oldset;
+ PublicInbox::DS::sig_setmask($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} = $$;
+ awaitpid($pid, \&ipc_worker_reap, $self);
$self->{-ipc_pid} = $pid;
}
-sub ipc_worker_reap { # dwaitpid callback
- my ($self, $pid) = @_;
- warn "PID:$pid died with \$?=$?\n" if $?;
+sub ipc_worker_reap { # awaitpid callback
+ my ($pid, $self) = @_;
+ delete $self->{-wq_workers}->{$pid};
+ if (my $cb_args = $self->{-reap_do}) {
+ return $cb_args->[0]->($pid, $self, @$cb_args[1..$#$cb_args]);
+ }
+ return if !$?;
+ my $s = $? & 127;
+ # TERM(15) is our default exit signal, PIPE(13) is likely w/ pager
+ warn "$self->{-wq_ident} PID:$pid died \$?=$?\n" if $s != 15 && $s != 13
+}
+
+# register wait workers
+sub awaitpid_init {
+ my ($self, @cb_args) = @_;
+ $self->{-reap_do} = \@cb_args;
}
# for base class, override in sub classes
-sub ipc_atfork_parent {}
-sub ipc_atfork_child {}
+sub ipc_atfork_prepare {}
-# should only be called inside the worker process
-sub ipc_worker_exit {
- my (undef, $code) = @_;
- exit($code);
+sub wq_atexit_child {}
+
+sub ipc_atfork_child {
+ my ($self) = @_;
+ my $io = delete($self->{-ipc_atfork_child_close}) or return;
+ close($_) for @$io;
+ undef;
}
# idempotent, can be called regardless of whether worker is active or not
return; # idempotent
}
die 'no PID with IPC pipes' unless $pid;
- _send_rec($w_req, [ undef, 'ipc_worker_exit', 0 ]);
$w_req = $r_res = undef;
-
- # allow any sibling to send ipc_worker_exit, but siblings can't wait
- return if $$ != $ppid;
- 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);
- }
+ awaitpid($pid) if $$ == $ppid; # for non-event loop
}
# use this if we have multiple readers reading curl or "pigz -dc"
# and writing to the same store
sub ipc_lock_init {
my ($self, $f) = @_;
+ $f // die 'BUG: no filename given';
require PublicInbox::Lock;
$self->{-ipc_lock} //= bless { lock_path => $f }, 'PublicInbox::Lock'
}
+sub _wait_return ($$) {
+ my ($r_res, $sub) = @_;
+ my $ret = _get_rec($r_res) // die "no response on $sub";
+ die $$ret if ref($ret) eq 'PublicInbox::IPC::Die';
+ wantarray ? @$ret : $$ret;
+}
+
# call $self->$sub(@args), on a worker if ipc_worker_spawn was used
sub ipc_do {
my ($self, $sub, @args) = @_;
if (defined(wantarray)) {
my $r_res = $self->{-ipc_res} or die 'no ipc_res';
_send_rec($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;
+ _wait_return($r_res, $sub);
} else { # likely, fire-and-forget into pipe
_send_rec($w_req, [ undef , $sub, @args ]);
}
$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 // $MY_MAX_ARG_STRLEN);
+ return if scalar(@fds) && !defined($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 "$$ open(+<&=$fd) (FD:$nfd): $!";
+ }
+ }
+ while ($full_stream && $n < $len) {
+ my $r = sysread($s2, $buf, $len - $n, $n) // croak "read: $!";
+ croak "read EOF after $n/$len bytes" if $r == 0;
+ $n = length($buf);
+ }
+ # Sereal dies on truncated data, Storable returns undef
+ my $args = ipc_thaw($buf) // die "thaw error on buffer of size: $n";
+ undef $buf;
+ my $sub = shift @$args;
+ eval { $self->$sub(@$args) };
+ warn "$$ $0 wq_worker: $sub: $@" if $@;
+ delete @$self{0..($nfd-1)};
+ $n;
+}
+
+sub wq_worker_loop ($$) {
+ my ($self, $bcast2) = @_;
+ my $wqw = PublicInbox::WQWorker->new($self, $self->{-wq_s2});
+ PublicInbox::WQWorker->new($self, $bcast2) if $bcast2;
+ PublicInbox::DS->SetPostLoopCallback(sub { $wqw->{sock} });
+ PublicInbox::DS::event_loop();
+ PublicInbox::DS->Reset;
+}
+
+sub do_sock_stream { # via wq_io_do, for big requests
+ my ($self, $len) = @_;
+ recv_and_run($self, my $s2 = delete $self->{0}, $len, 1);
+}
+
+sub wq_broadcast {
+ my ($self, $sub, @args) = @_;
+ if (my $wkr = $self->{-wq_workers}) {
+ my $buf = ipc_freeze([$sub, @args]);
+ for my $bcast1 (values %$wkr) {
+ my $sock = $bcast1 // $self->{-wq_s1} // next;
+ send($sock, $buf, MSG_EOR) // croak "send: $!";
+ # XXX shouldn't have to deal with EMSGSIZE here...
+ }
+ } else {
+ eval { $self->$sub(@args) };
+ warn "wq_broadcast: $@" if $@;
+ }
+}
+
+sub stream_in_full ($$$) {
+ my ($s1, $fds, $buf) = @_;
+ socketpair(my $r, my $w, AF_UNIX, SOCK_STREAM, 0) or
+ croak "socketpair: $!";
+ my $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 += $x;
+ }
+}
+
+sub wq_io_do { # always async
+ my ($self, $sub, $ios, @args) = @_;
+ if (my $s1 = $self->{-wq_s1}) { # run in worker
+ my $fds = [ map { fileno($_) } @$ios ];
+ my $buf = ipc_freeze([$sub, @args]);
+ if (length($buf) > $MY_MAX_ARG_STRLEN) {
+ stream_in_full($s1, $fds, $buf);
+ } else {
+ my $n = $send_cmd->($s1, $fds, $buf, MSG_EOR);
+ return if defined($n); # likely
+ $!{ETOOMANYREFS} and
+ croak "sendmsg: $! (check RLIMIT_NOFILE)";
+ $!{EMSGSIZE} ? stream_in_full($s1, $fds, $buf) :
+ croak("sendmsg: $!");
+ }
+ } else {
+ @$self{0..$#$ios} = @$ios;
+ eval { $self->$sub(@args) };
+ warn "wq_io_do: $@" if $@;
+ delete @$self{0..$#$ios}; # don't close
+ }
+}
+
+sub wq_sync_run {
+ my ($self, $wantarray, $sub, @args) = @_;
+ if ($wantarray) {
+ my @ret = eval { $self->$sub(@args) };
+ ipc_return($self->{0}, \@ret, $@);
+ } else { # '' => wantscalar
+ my $ret = eval { $self->$sub(@args) };
+ ipc_return($self->{0}, \$ret, $@);
+ }
+}
+
+sub wq_do {
+ my ($self, $sub, @args) = @_;
+ if (defined(wantarray)) {
+ pipe(my ($r, $w)) or die "pipe: $!";
+ wq_io_do($self, 'wq_sync_run', [ $w ], wantarray, $sub, @args);
+ undef $w;
+ _wait_return($r, $sub);
+ } else {
+ wq_io_do($self, $sub, [], @args);
+ }
+}
+
+sub prepare_nonblock {
+ ($_[0]->{-wq_s1} // die 'BUG: no {-wq_s1}')->blocking(0);
+ $_[0]->{-reap_do} or die 'BUG: {-reap_do} needed for nonblock';
+ require PublicInbox::WQBlocked;
+}
+
+sub wq_nonblock_do { # always async
+ my ($self, $sub, @args) = @_;
+ my $buf = ipc_freeze([$sub, @args]);
+ if ($self->{wqb}) { # saturated once, assume saturated forever
+ $self->{wqb}->flush_send($buf);
+ } else {
+ $send_cmd->($self->{-wq_s1}, [], $buf, MSG_EOR) //
+ ($!{EAGAIN} ? PublicInbox::WQBlocked->new($self, $buf)
+ : croak("sendmsg: $!"));
+ }
+}
+
+sub _wq_worker_start ($$$$) {
+ my ($self, $oldset, $fields, $one) = @_;
+ my ($bcast1, $bcast2);
+ $one or socketpair($bcast1, $bcast2, AF_UNIX, $SEQPACKET, 0) or
+ die "socketpair: $!";
+ my $seed = rand(0xffffffff);
+ my $pid = fork // die "fork: $!";
+ if ($pid == 0) {
+ srand($seed);
+ eval { Net::SSLeay::randomize() };
+ undef $bcast1;
+ eval { PublicInbox::DS->Reset };
+ delete @$self{qw(-wq_s1 -wq_ppid)};
+ $self->{-wq_worker_nr} =
+ keys %{delete($self->{-wq_workers}) // {}};
+ $SIG{$_} = 'DEFAULT' for (qw(TTOU TTIN TERM QUIT INT CHLD));
+ local $0 = $one ? $self->{-wq_ident} :
+ "$self->{-wq_ident} $self->{-wq_worker_nr}";
+ # ensure we properly exit even if warn() dies:
+ my $end = PublicInbox::OnDestroy->new($$, sub { exit(!!$@) });
+ eval {
+ $fields //= {};
+ local @$self{keys %$fields} = values(%$fields);
+ my $on_destroy = $self->ipc_atfork_child;
+ local @SIG{keys %SIG} = values %SIG;
+ PublicInbox::DS::sig_setmask($oldset);
+ wq_worker_loop($self, $bcast2);
+ };
+ warn "worker $self->{-wq_ident} PID:$$ died: $@" if $@;
+ undef $end; # trigger exit
+ } else {
+ $self->{-wq_workers}->{$pid} = $bcast1;
+ awaitpid($pid, \&ipc_worker_reap, $self);
+ }
+}
+
+# starts workqueue workers if Sereal or Storable is installed
+sub wq_workers_start {
+ my ($self, $ident, $nr_workers, $oldset, $fields) = @_;
+ ($send_cmd && $recv_cmd && defined($SEQPACKET)) or return;
+ return if $self->{-wq_s1}; # idempotent
+ $self->{-wq_s1} = $self->{-wq_s2} = undef;
+ socketpair($self->{-wq_s1}, $self->{-wq_s2}, AF_UNIX, $SEQPACKET, 0) or
+ die "socketpair: $!";
+ $self->ipc_atfork_prepare;
+ $nr_workers //= $self->{-wq_nr_workers}; # was set earlier
+ my $sigset = $oldset // PublicInbox::DS::block_signals();
+ $self->{-wq_workers} = {};
+ $self->{-wq_ident} = $ident;
+ my $one = $nr_workers == 1;
+ $self->{-wq_nr_workers} = $nr_workers;
+ _wq_worker_start($self, $sigset, $fields, $one) for (1..$nr_workers);
+ PublicInbox::DS::sig_setmask($sigset) unless $oldset;
+ $self->{-wq_ppid} = $$;
+}
+
+sub wq_close {
+ my ($self) = @_;
+ if (my $wqb = delete $self->{wqb}) {
+ $self->{-reap_do} or die 'BUG: {-reap_do} unset';
+ $wqb->enq_close;
+ }
+ delete @$self{qw(-wq_s1 -wq_s2)} or return;
+ return if $self->{-reap_do};
+ awaitpid($_) for keys %{$self->{-wq_workers}};
+}
+
+sub wq_kill {
+ my ($self, $sig) = @_;
+ kill($sig // 'TERM', keys %{$self->{-wq_workers}});
+}
+
+sub DESTROY {
+ my ($self) = @_;
+ my $ppid = $self->{-wq_ppid};
+ wq_kill($self) if $ppid && $ppid == $$;
+ wq_close($self);
+ ipc_worker_stop($self);
+}
+
+sub detect_nproc () {
+ # _SC_NPROCESSORS_ONLN = 84 on both Linux glibc and musl
+ return POSIX::sysconf(84) if $^O eq 'linux';
+ return POSIX::sysconf(58) if $^O eq 'freebsd';
+ # TODO: more OSes
+
+ # getconf(1) is POSIX, but *NPROCESSORS* vars are not
+ for (qw(_NPROCESSORS_ONLN NPROCESSORS_ONLN)) {
+ `getconf $_ 2>/dev/null` =~ /^(\d+)$/ and return $1;
+ }
+ for my $nproc (qw(nproc gnproc)) { # GNU coreutils nproc
+ `$nproc 2>/dev/null` =~ /^(\d+)$/ and return $1;
+ }
+
+ # should we bother with `sysctl hw.ncpu`? Those only give
+ # us total processor count, not online processor count.
+ undef
+}
+
1;