ds: use object-oriented API for epoll

This allows us to cut down on imports and reduce code.
This also makes it easier (in the next commit) to provide an option
to disable epoll/kqueue when saving an FD is valued over scalability.

1 files changed, 14 insertions, 26 deletions

diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm
index d6e3d10e..9300ac77 100644
--- a/lib/PublicInbox/DS.pm
+++ b/lib/PublicInbox/DS.pm
@@ -28,7 +28,8 @@ use POSIX qw(WNOHANG sigprocmask SIG_SETMASK SIG_UNBLOCK);
 use Fcntl qw(SEEK_SET :DEFAULT O_APPEND);
 use Time::HiRes qw(clock_gettime CLOCK_MONOTONIC);
 use Scalar::Util qw(blessed);
-use PublicInbox::Syscall qw(:epoll %SIGNUM);
+use PublicInbox::Syscall qw(%SIGNUM
+        EPOLLIN EPOLLOUT EPOLLONESHOT EPOLLEXCLUSIVE);
 use PublicInbox::Tmpfile;
 use Errno qw(EAGAIN EINVAL ECHILD EINTR);
 use Carp qw(carp croak);
@@ -41,8 +42,7 @@ my $reap_armed;
 my $ToClose; # sockets to close when event loop is done
 our (
      %DescriptorMap,             # fd (num) -> PublicInbox::DS object
-     $Epoll,                     # Global epoll fd (or DSKQXS ref)
-     $ep_io,                     # IO::Handle for Epoll
+     $Epoll,  # global Epoll, DSPoll, or DSKQXS ref
 
      @post_loop_do,              # subref + args to call at the end of each loop
 
@@ -75,7 +75,6 @@ sub Reset {
                 my @q = delete @Stack{keys %Stack};
                 for my $q (@q) { @$q = () }
                 $AWAIT_PIDS = $nextq = $ToClose = undef;
-                $ep_io = undef; # closes real $Epoll FD
                 $Epoll = undef; # may call DSKQXS::DESTROY
         } while (@Timers || keys(%Stack) || $nextq || $AWAIT_PIDS ||
                 $ToClose || keys(%DescriptorMap) ||
@@ -126,21 +125,13 @@ sub add_uniq_timer { # ($name, $secs, $coderef, @args) = @_;
 
 # caller sets return value to $Epoll
 sub _InitPoller () {
-        if (defined $PublicInbox::Syscall::SYS_epoll_create)  {
-                my $fd = epoll_create();
-                die "epoll_create: $!" if $fd < 0;
-                open($ep_io, '+<&=', $fd) or return;
-                fcntl($ep_io, F_SETFD, FD_CLOEXEC);
-                $fd;
-        } else {
-                my $cls;
-                for (qw(DSKQXS DSPoll)) {
-                        $cls = "PublicInbox::$_";
-                        last if eval "require $cls";
-                }
-                $cls->import(qw(epoll_ctl epoll_wait));
-                $cls->new;
+        my @try = ($^O eq 'linux' ? 'Epoll' : 'DSKQXS');
+        my $cls;
+        for (@try, 'DSPoll') {
+                $cls = "PublicInbox::$_";
+                last if eval "require $cls";
         }
+        $cls->new;
 }
 
 sub now () { clock_gettime(CLOCK_MONOTONIC) }
@@ -307,7 +298,7 @@ sub event_loop (;$$) {
                 my $timeout = RunTimers();
 
                 # get up to 1000 events
-                epoll_wait($Epoll, 1000, $timeout, \@events);
+                $Epoll->ep_wait(1000, $timeout, \@events);
                 for my $fd (@events) {
                         # it's possible epoll_wait returned many events,
                         # including some at the end that ones in the front
@@ -345,7 +336,7 @@ sub new {
 
     $Epoll //= _InitPoller();
 retry:
-    if (epoll_ctl($Epoll, EPOLL_CTL_ADD, $fd, $ev)) {
+    if ($Epoll->ep_add($sock, $ev)) {
         if ($! == EINVAL && ($ev & EPOLLEXCLUSIVE)) {
             $ev &= ~EPOLLEXCLUSIVE;
             goto retry;
@@ -399,9 +390,7 @@ sub close {
 
     # if we're using epoll, we have to remove this from our epoll fd so we stop getting
     # notifications about it
-    my $fd = fileno($sock);
-    epoll_ctl($Epoll, EPOLL_CTL_DEL, $fd, 0) and
-        croak("EPOLL_CTL_DEL($self/$sock): $!");
+    $Epoll->ep_del($sock) and croak("EPOLL_CTL_DEL($self/$sock): $!");
 
     # we explicitly don't delete from DescriptorMap here until we
     # actually close the socket, as we might be in the middle of
@@ -619,9 +608,8 @@ sub msg_more ($$) {
 }
 
 sub epwait ($$) {
-    my ($sock, $ev) = @_;
-    epoll_ctl($Epoll, EPOLL_CTL_MOD, fileno($sock), $ev) and
-        croak("EPOLL_CTL_MOD($sock): $!");
+        my ($io, $ev) = @_;
+        $Epoll->ep_mod($io, $ev) and croak("EPOLL_CTL_MOD($io): $!");
 }
 
 # return true if complete, false if incomplete (or failure)