X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FDS.pm;h=970061fd55f1c44c77d51084d7d9891aeb3f48f3;hb=8775167475d8bfc25d532b777147a8b1ef1cd99b;hp=b16b189629ff16d459bc7c79bb0155e43d9642ea;hpb=a3c054cbbf2a51be121b3237c5d223acc5c8a2f4;p=public-inbox.git diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm index b16b1896..970061fd 100644 --- a/lib/PublicInbox/DS.pm +++ b/lib/PublicInbox/DS.pm @@ -3,20 +3,20 @@ # # This license differs from the rest of public-inbox # -# This is a fork of the (for now) unmaintained Danga::Socket 1.61. -# Unused features will be removed, and updates will be made to take -# advantage of newer kernels. +# This is a fork of the unmaintained Danga::Socket (1.61) with +# significant changes. See Documentation/technical/ds.txt in our +# source for details. # -# API changes to diverge from Danga::Socket will happen to better -# accomodate new features and improve scalability. Do not expect -# this to be a stable API like Danga::Socket. -# Bugs encountered (and likely fixed) are reported to -# bug-Danga-Socket@rt.cpan.org and visible at: +# Do not expect this to be a stable API like Danga::Socket, +# but it will evolve to suite our needs and to take advantage of +# newer Linux and *BSD features. +# Bugs encountered were reported to bug-Danga-Socket@rt.cpan.org, +# fixed in Danga::Socket 1.62 and visible at: # https://rt.cpan.org/Public/Dist/Display.html?Name=Danga-Socket package PublicInbox::DS; use strict; use bytes; -use POSIX (); +use POSIX qw(WNOHANG); use IO::Handle qw(); use Fcntl qw(SEEK_SET :DEFAULT); use Time::HiRes qw(clock_gettime CLOCK_MONOTONIC); @@ -24,31 +24,38 @@ use parent qw(Exporter); our @EXPORT_OK = qw(now msg_more); use warnings; use 5.010_001; +use Scalar::Util qw(blessed); use PublicInbox::Syscall qw(:epoll); +use PublicInbox::Tmpfile; use fields ('sock', # underlying socket 'rbuf', # scalarref, usually undef - 'wbuf', # arrayref of coderefs or GLOB refs + 'wbuf', # arrayref of coderefs or GLOB refs (autovivified) 'wbuf_off', # offset into first element of wbuf to start writing at ); -use Errno qw(EAGAIN EINVAL EEXIST); -use Carp qw(croak confess carp); -require File::Spec; +use Errno qw(EAGAIN EINVAL); +use Carp qw(confess carp); -my $nextq = []; # queue for next_tick +my $nextq; # queue for next_tick +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 our ( %DescriptorMap, # fd (num) -> PublicInbox::DS object $Epoll, # Global epoll fd (or DSKQXS ref) $_io, # IO::Handle for Epoll - @ToClose, # sockets to close when event loop is done $PostLoopCallback, # subref to call at the end of each loop, if defined (global) $LoopTimeout, # timeout of event loop in milliseconds $DoneInit, # if we've done the one-time module init yet @Timers, # timers + $in_loop, ); Reset(); @@ -64,7 +71,9 @@ Reset all state =cut sub Reset { %DescriptorMap = (); - @ToClose = (); + $wait_pids = $later_queue = undef; + $EXPMAP = {}; + $nextq = $ToClose = $reap_timer = $later_timer = $exp_timer = undef; $LoopTimeout = -1; # no timeout by default @Timers = (); @@ -89,20 +98,18 @@ sub SetLoopTimeout { return $LoopTimeout = $_[1] + 0; } -=head2 C<< CLASS->AddTimer( $seconds, $coderef ) >> +=head2 C<< PublicInbox::DS::add_timer( $seconds, $coderef ) >> Add a timer to occur $seconds from now. $seconds may be fractional, but timers are not guaranteed to fire at the exact time you ask for. -Returns a timer object which you can call C<< $timer->cancel >> on if you need to. - =cut -sub AddTimer { - my ($class, $secs, $coderef) = @_; +sub add_timer ($$) { + my ($secs, $coderef) = @_; my $fire_time = now() + $secs; - my $timer = bless [$fire_time, $coderef], "PublicInbox::DS::Timer"; + my $timer = [$fire_time, $coderef]; if (!@Timers || $fire_time >= $Timers[-1][0]) { push @Timers, $timer; @@ -170,13 +177,15 @@ sub FirstTimeEventLoop { sub now () { clock_gettime(CLOCK_MONOTONIC) } sub next_tick () { - my $q = $nextq; - $nextq = []; + my $q = $nextq or return; + $nextq = undef; for (@$q) { - if (ref($_) eq 'CODE') { - $_->(); - } else { + # we avoid "ref" on blessed refs to workaround a Perl 5.16.3 leak: + # https://rt.perl.org/Public/Bug/Display.html?id=114340 + if (blessed($_)) { $_->event_step; + } else { + $_->(); } } } @@ -185,7 +194,7 @@ sub next_tick () { sub RunTimers { next_tick(); - return ((@$nextq || @ToClose) ? 0 : $LoopTimeout) unless @Timers; + return (($nextq || $ToClose) ? 0 : $LoopTimeout) unless @Timers; my $now = now(); @@ -196,7 +205,7 @@ sub RunTimers { } # timers may enqueue into nextq: - return 0 if (@$nextq || @ToClose); + return 0 if ($nextq || $ToClose); return $LoopTimeout unless @Timers; @@ -215,8 +224,57 @@ sub RunTimers { return $timeout; } +# We can't use waitpid(-1) safely here since it can hit ``, system(), +# 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 = $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 @$wait_pids, $ary; # autovivifies @$wait_pids + } elsif ($cb) { + eval { $cb->($arg, $pid) }; + } + } + # 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) +sub enqueue_reap ($) { push @$nextq, \&reap_pids }; # autovivifies + +sub in_loop () { $in_loop } + +# Internal function: run the post-event callback, send read events +# for pushed-back data, and close pending connections. returns 1 +# if event loop should continue, or 0 to shut it all down. +sub PostEventLoop () { + # now we can close sockets that wanted to close during our event + # processing. (we didn't want to close them during the loop, as we + # didn't want fd numbers being reused and confused during the event + # 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{@$close_now}; + } + + # by default we keep running, unless a postloop callback cancels it + $PostLoopCallback ? $PostLoopCallback->(\%DescriptorMap) : 1; +} + sub EpollEventLoop { - while (1) { + local $in_loop = 1; + do { my @events; my $i; my $timeout = RunTimers(); @@ -230,8 +288,8 @@ sub EpollEventLoop { # in that event. $DescriptorMap{$events[$i]->[0]}->event_step; } - return unless PostEventLoop(); - } + } while (PostEventLoop()); + _run_later(); } =head2 C<< CLASS->SetPostLoopCallback( CODEREF ) >> @@ -252,28 +310,6 @@ sub SetPostLoopCallback { $PostLoopCallback = (defined $ref && ref $ref eq 'CODE') ? $ref : undef; } -# Internal function: run the post-event callback, send read events -# for pushed-back data, and close pending connections. returns 1 -# if event loop should continue, or 0 to shut it all down. -sub PostEventLoop { - # now we can close sockets that wanted to close during our event processing. - # (we didn't want to close them during the loop, as we didn't want fd numbers - # being reused and confused during the event loop) - delete($DescriptorMap{fileno($_)}) for @ToClose; - @ToClose = (); # let refcounting drop everything all at once - - # by default we keep running, unless a postloop callback (either per-object - # or global) cancels it - my $keep_running = 1; - - # now we're at the very end, call callback if defined - if (defined $PostLoopCallback) { - $keep_running &&= $PostLoopCallback->(\%DescriptorMap); - } - - return $keep_running; -} - ##################################################################### ### PublicInbox::DS-the-object code ##################################################################### @@ -297,9 +333,6 @@ sub new { $self->{sock} = $sock; my $fd = fileno($sock); - Carp::cluck("undef sock and/or fd in PublicInbox::DS->new. sock=" . ($sock || "") . ", fd=" . ($fd || "")) - unless $sock && $fd; - _InitPoller(); if (epoll_ctl($Epoll, EPOLL_CTL_ADD, $fd, $ev)) { @@ -309,11 +342,10 @@ sub new { } die "couldn't add epoll watch for $fd: $!\n"; } - Carp::cluck("PublicInbox::DS::new blowing away existing descriptor map for fd=$fd ($DescriptorMap{$fd})") - if $DescriptorMap{$fd}; + confess("DescriptorMap{$fd} defined ($DescriptorMap{$fd})") + if defined($DescriptorMap{$fd}); $DescriptorMap{$fd} = $self; - return $self; } @@ -321,7 +353,7 @@ sub new { ### I N S T A N C E M E T H O D S ##################################################################### -sub requeue ($) { push @$nextq, $_[0] } +sub requeue ($) { push @$nextq, $_[0] } # autovivifies =head2 C<< $obj->close >> @@ -354,7 +386,7 @@ sub close { # defer closing the actual socket until the event loop is done # processing this round of events. (otherwise we might reuse fds) - push @ToClose, $sock; + push @$ToClose, $sock; # autovivifies $ToClose return 0; } @@ -458,15 +490,8 @@ sub drop { # PerlIO::mmap or PerlIO::scalar if needed sub tmpio ($$$) { my ($self, $bref, $off) = @_; - my $fh; # open(my $fh, '+>>', undef) doesn't set O_APPEND - do { - my $fn = File::Spec->tmpdir . '/wbuf-' . rand; - if (sysopen($fh, $fn, O_RDWR|O_CREAT|O_EXCL|O_APPEND, 0600)) { # likely - unlink($fn) or return drop($self, "unlink($fn) $!"); - } elsif ($! != EEXIST) { # EMFILE/ENFILE/ENOSPC/ENOMEM - return drop($self, "open: $!"); - } - } until (defined $fh); + my $fh = tmpfile('wbuf', $self->{sock}, 1) or + return drop($self, "tmpfile $!"); $fh->autoflush(1); my $len = bytes::length($$bref) - $off; $fh->write($$bref, $len, $off) or return drop($self, "write ($len): $!"); @@ -530,7 +555,7 @@ sub write { # wbuf may be an empty array if we're being called inside # ->flush_write via CODE bref: - push @{$self->{wbuf} ||= []}, $tmpio; + push @{$self->{wbuf}}, $tmpio; # autovivifies return 0; } } @@ -540,15 +565,17 @@ use constant MSG_MORE => ($^O eq 'linux') ? 0x8000 : 0; sub msg_more ($$) { my $self = $_[0]; my $sock = $self->{sock} or return 1; + my $wbuf = $self->{wbuf}; - if (MSG_MORE && !$self->{wbuf} && ref($sock) ne 'IO::Socket::SSL') { + if (MSG_MORE && (!defined($wbuf) || !scalar(@$wbuf)) && + ref($sock) ne 'IO::Socket::SSL') { my $n = send($sock, $_[1], MSG_MORE); if (defined $n) { my $nlen = bytes::length($_[1]) - $n; return 1 if $nlen == 0; # all done! # queue up the unwritten substring: my $tmpio = tmpio($self, \($_[1]), $n) or return 0; - $self->{wbuf} = [ $tmpio ]; + push @{$self->{wbuf}}, $tmpio; # autovivifies epwait($sock, EPOLLOUT|EPOLLONESHOT); return 0; } @@ -571,7 +598,7 @@ sub accept_tls_step ($) { return 1 if $sock->accept_SSL; return $self->close if $! != EAGAIN; epwait($sock, PublicInbox::TLS::epollbit() | EPOLLONESHOT); - unshift @{$self->{wbuf} ||= []}, \&accept_tls_step; + unshift(@{$self->{wbuf}}, \&accept_tls_step); # autovivifies 0; } @@ -582,7 +609,7 @@ sub shutdn_tls_step ($) { return $self->close if $sock->stop_SSL(SSL_fast_shutdown => 1); return $self->close if $! != EAGAIN; epwait($sock, PublicInbox::TLS::epollbit() | EPOLLONESHOT); - unshift @{$self->{wbuf} ||= []}, \&shutdn_tls_step; + unshift(@{$self->{wbuf}}, \&shutdn_tls_step); # autovivifies 0; } @@ -597,10 +624,56 @@ sub shutdn ($) { $self->close; } } -package PublicInbox::DS::Timer; -# [$abs_float_firetime, $coderef]; -sub cancel { - $_[0][1] = undef; + +# must be called with eval, PublicInbox::DS may not be loaded (see t/qspawn.t) +sub dwaitpid ($$$) { + 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); +} + +sub _run_later () { + my $run = $later_queue or return; + $later_timer = $later_queue = undef; + $_->() for @$run; +} + +sub 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, $idle_at) = each %$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(); + $exp_timer //= later(\&expire_old); +} + +sub not_idle_long { + my ($self, $now) = @_; + my $sock = $self->{sock} or return; + my $idle_at = $EXPMAP->{fileno($sock)} or return; + ($idle_at + $EXPTIME) > $now; } 1;