treewide: avoid getpid for more ownership checks

There are still some places where on_destroy isn't suitable,
This gets rid of getpid() calls in most of those cases to
reduce syscall costs and cleanup syscall trace output.

5 files changed, 28 insertions, 32 deletions

diff --git a/lib/PublicInbox/DSKQXS.pm b/lib/PublicInbox/DSKQXS.pm
index f84c196a..dc6621e4 100644
--- a/lib/PublicInbox/DSKQXS.pm
+++ b/lib/PublicInbox/DSKQXS.pm
@@ -15,6 +15,7 @@ use v5.12;
 use Symbol qw(gensym);
 use IO::KQueue;
 use Errno qw(EAGAIN);
+use PublicInbox::OnDestroy;
 use PublicInbox::Syscall qw(EPOLLONESHOT EPOLLIN EPOLLOUT EPOLLET);
 
 sub EV_DISPATCH () { 0x0080 }
@@ -37,7 +38,8 @@ sub kq_flag ($$) {
 
 sub new {
         my ($class) = @_;
-        bless { kq => IO::KQueue->new, owner_pid => $$ }, $class;
+        my $fgen = $PublicInbox::OnDestroy::fork_gen;
+        bless { kq => IO::KQueue->new, fgen => $fgen }, $class;
 }
 
 # returns a new instance which behaves like signalfd on Linux.
@@ -137,9 +139,8 @@ sub ep_wait {
 sub DESTROY {
         my ($self) = @_;
         my $kq = delete $self->{kq} or return;
-        if (delete($self->{owner_pid}) == $$) {
+        delete($self->{fgen}) == $PublicInbox::OnDestroy::fork_gen and
                 POSIX::close($$kq);
-        }
 }
 
 1;
diff --git a/lib/PublicInbox/Daemon.pm b/lib/PublicInbox/Daemon.pm
index 1cc0c9e6..ec76d6b8 100644
--- a/lib/PublicInbox/Daemon.pm
+++ b/lib/PublicInbox/Daemon.pm
@@ -352,8 +352,7 @@ EOF
         return unless defined $pid_file;
 
         write_pid($pid_file);
-        # for ->DESTROY:
-        bless { pid => $$, pid_file => \$pid_file }, __PACKAGE__;
+        on_destroy \&unlink_pid_file_safe_ish, \$pid_file;
 }
 
 sub has_busy_clients { # post_loop_do CB
@@ -476,7 +475,7 @@ sub upgrade { # $_[0] = signal name or number (unused)
                         warn "BUG: .oldbin suffix exists: $pid_file\n";
                         return;
                 }
-                unlink_pid_file_safe_ish($$, $pid_file);
+                unlink_pid_file_safe_ish(\$pid_file);
                 $pid_file .= '.oldbin';
                 write_pid($pid_file);
         }
@@ -509,23 +508,20 @@ sub upgrade_aborted {
 
         my $file = $pid_file;
         $file =~ s/\.oldbin\z// or die "BUG: no '.oldbin' suffix in $file";
-        unlink_pid_file_safe_ish($$, $pid_file);
+        unlink_pid_file_safe_ish(\$pid_file);
         $pid_file = $file;
         eval { write_pid($pid_file) };
         warn $@, "\n" if $@;
 }
 
-sub unlink_pid_file_safe_ish ($$) {
-        my ($unlink_pid, $file) = @_;
-        return unless defined $unlink_pid && $unlink_pid == $$;
+sub unlink_pid_file_safe_ish ($) {
+        my ($fref) = @_;
 
-        open my $fh, '<', $file or return;
+        open my $fh, '<', $$fref or return;
         local $/ = "\n";
         defined(my $read_pid = <$fh>) or return;
         chomp $read_pid;
-        if ($read_pid == $unlink_pid) {
-                Net::Server::Daemonize::unlink_pid_file($file);
-        }
+        Net::Server::Daemonize::unlink_pid_file($$fref) if $read_pid == $$;
 }
 
 sub master_quit ($) {
@@ -696,7 +692,7 @@ sub run {
         $nworker = 1;
         local (%XNETD, %POST_ACCEPT);
         daemon_prepare($default_listen);
-        my $for_destroy = daemonize();
+        my $unlink_on_leave = daemonize();
 
         # localize GCF2C for tests:
         local $PublicInbox::GitAsyncCat::GCF2C;
@@ -706,7 +702,7 @@ sub run {
         local %POST_ACCEPT;
 
         daemon_loop();
-        # ->DESTROY runs when $for_destroy goes out-of-scope
+        # $unlink_on_leave runs
 }
 
 sub write_pid ($) {
@@ -715,8 +711,4 @@ sub write_pid ($) {
         do_chown($path);
 }
 
-sub DESTROY {
-        unlink_pid_file_safe_ish($_[0]->{pid}, ${$_[0]->{pid_file}});
-}
-
 1;
diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index af12f141..aea389e8 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -210,14 +210,14 @@ sub cat_async_retry ($$) {
 sub gcf_inflight ($) {
         my ($self) = @_;
         # FIXME: the first {sock} check can succeed but Perl can complain
-        # about calling ->owner_pid on an undefined value.  Not sure why or
-        # how this happens but t/imapd.t can complain about it, sometimes.
+        # about an undefined value.  Not sure why or how this happens but
+        # t/imapd.t can complain about it, sometimes.
         if ($self->{sock}) {
-                if (eval { $self->{sock}->owner_pid == $$ }) {
+                if (eval { $self->{sock}->can_reap }) {
                         return $self->{inflight};
                 } elsif ($@) {
                         no warnings 'uninitialized';
-                        warn "E: $self sock=$self->{sock}: owner_pid failed: ".
+                        warn "E: $self sock=$self->{sock}: can_reap failed: ".
                                 "$@ (continuing...)";
                 }
                 delete @$self{qw(sock inflight)};
diff --git a/lib/PublicInbox/IO.pm b/lib/PublicInbox/IO.pm
index 5654f3b0..02057600 100644
--- a/lib/PublicInbox/IO.pm
+++ b/lib/PublicInbox/IO.pm
@@ -10,6 +10,7 @@ our @EXPORT_OK = qw(poll_in read_all try_cat write_file);
 use Carp qw(croak);
 use IO::Poll qw(POLLIN);
 use Errno qw(EINTR EAGAIN);
+use PublicInbox::OnDestroy;
 # don't autodie in top-level for Perl 5.16.3 (and maybe newer versions)
 # we have our own ->close, so we scope autodie into each sub
 
@@ -23,7 +24,8 @@ sub attach_pid {
         my ($io, $pid, @cb_arg) = @_;
         bless $io, __PACKAGE__;
         # we share $err (and not $self) with awaitpid to avoid a ref cycle
-        ${*$io}{pi_io_reap} = [ $$, $pid, \(my $err) ];
+        ${*$io}{pi_io_reap} = [ $PublicInbox::OnDestroy::fork_gen,
+                                $pid, \(my $err) ];
         awaitpid($pid, \&waitcb, \$err, @cb_arg);
         $io;
 }
@@ -33,9 +35,9 @@ sub attached_pid {
         ${${*$io}{pi_io_reap} // []}[1];
 }
 
-sub owner_pid {
+sub can_reap {
         my ($io) = @_;
-        ${${*$io}{pi_io_reap} // [-1]}[0];
+        ${${*$io}{pi_io_reap} // [-1]}[0] == $PublicInbox::OnDestroy::fork_gen;
 }
 
 # caller cares about error result if they call close explicitly
@@ -44,7 +46,7 @@ sub close {
         my ($io) = @_;
         my $ret = $io->SUPER::close;
         my $reap = delete ${*$io}{pi_io_reap};
-        return $ret unless $reap && $reap->[0] == $$;
+        return $ret if ($reap->[0] // -1) != $PublicInbox::OnDestroy::fork_gen;
         if (defined ${$reap->[2]}) { # reap_pids already reaped asynchronously
                 $? = ${$reap->[2]};
         } else { # wait synchronously
@@ -56,7 +58,7 @@ sub close {
 sub DESTROY {
         my ($io) = @_;
         my $reap = delete ${*$io}{pi_io_reap};
-        if ($reap && $reap->[0] == $$) {
+        if (($reap->[0] // -1) == $PublicInbox::OnDestroy::fork_gen) {
                 $io->SUPER::close;
                 awaitpid($reap->[1]);
         }
diff --git a/lib/PublicInbox/LeiALE.pm b/lib/PublicInbox/LeiALE.pm
index 528de22c..ce03f5b4 100644
--- a/lib/PublicInbox/LeiALE.pm
+++ b/lib/PublicInbox/LeiALE.pm
@@ -11,6 +11,7 @@ use parent qw(PublicInbox::LeiSearch PublicInbox::Lock);
 use PublicInbox::Git;
 use autodie qw(close open rename seek truncate);
 use PublicInbox::Import;
+use PublicInbox::OnDestroy;
 use PublicInbox::LeiXSearch;
 use Fcntl qw(SEEK_SET);
 
@@ -41,11 +42,11 @@ sub over {} # undef for xoids_for
 
 sub overs_all { # for xoids_for (called only in lei workers?)
         my ($self) = @_;
-        my $pid = $$;
-        if (($self->{owner_pid} // $pid) != $pid) {
+        my $fgen = $PublicInbox::OnDestroy::fork_gen ;
+        if (($self->{fgen} // $fgen) != $fgen) {
                 delete($_->{over}) for @{$self->{ibxish}};
         }
-        $self->{owner_pid} = $pid;
+        $self->{fgen} = $fgen;
         grep(defined, map { $_->over } @{$self->{ibxish}});
 }