Author: arkurth
Date: Wed Feb 1 18:28:36 2017
New Revision: 1781295
URL: http://svn.apache.org/viewvc?rev=1781295&view=rev
Log:
VCL-924
Determined running lsof command on management node is unsafe and commented out
code. It was only used for vcld.log informational purposes do determine which
process owned a lock on a file. The lsof command occasionally sends ALRM
signals which may cause vcld processes to behave badly.
Modified:
vcl/trunk/managementnode/lib/VCL/Module/Semaphore.pm
Modified: vcl/trunk/managementnode/lib/VCL/Module/Semaphore.pm
URL:
http://svn.apache.org/viewvc/vcl/trunk/managementnode/lib/VCL/Module/Semaphore.pm?rev=1781295&r1=1781294&r2=1781295&view=diff
==============================================================================
--- vcl/trunk/managementnode/lib/VCL/Module/Semaphore.pm (original)
+++ vcl/trunk/managementnode/lib/VCL/Module/Semaphore.pm Wed Feb 1 18:28:36
2017
@@ -58,14 +58,13 @@ use 5.008000;
use strict;
use warnings;
use diagnostics;
+
use English qw( -no_match_vars );
use IO::File;
-use Fcntl qw(:DEFAULT :flock);
+use Fcntl qw(:flock);
use VCL::utils;
-no warnings 'redefine';
-
##############################################################################
=head1 CLASS VARIABLES
@@ -196,86 +195,89 @@ sub open_lockfile {
return;
}
- # Determine which process is locking the file
- my @locking_pids = $self->get_lockfile_owning_pid($file_path);
- if (@locking_pids) {
- if (grep { $_ eq $PID } @locking_pids) {
- # The current process already has an exclusive lock on
the file
- # This could happen if open_lockfile is called more
than once for the same file in the same scope
- notify($ERRORS{'WARNING'}, 0, "file is already locked
by this process: @locking_pids");
- return;
- }
- else {
- # Attempt to retrieve the names of the locking
process(es)
- my ($ps_exit_status, $ps_output) = run_command("ps -o
pid=,cmd= @locking_pids", 1);
- if (defined($ps_output) && !grep(/(ps:)/, @$ps_output))
{
- notify($ERRORS{'DEBUG'}, 0, "file is locked by
another process: @locking_pids\n" . join("\n", @$ps_output));
- }
- else {
- notify($ERRORS{'DEBUG'}, 0, "file is locked by
another process: @locking_pids");
- }
- return;
- }
- }
- else {
- notify($ERRORS{'DEBUG'}, 0, "unable to determine PIDs of
processes which prevented an exclusive lock to be obtained on $file_path, lock
may have been released before lsof command was executed");
- }
+ # Don't use get_lockfile_owning_pid or anything that uses lsof on the
management node
+ # Not safe - seems to send ALRM some time after command seems to have
run
+ ## Determine which process is locking the file
+ #my @locking_pids = $self->get_lockfile_owning_pid($file_path);
+ #if (@locking_pids) {
+ # if (grep { $_ eq $PID } @locking_pids) {
+ # # The current process already has an exclusive lock on
the file
+ # # This could happen if open_lockfile is called more
than once for the same file in the same scope
+ # notify($ERRORS{'WARNING'}, 0, "file is already locked
by this process: @locking_pids");
+ # return;
+ # }
+ # else {
+ # # Attempt to retrieve the names of the locking
process(es)
+ # my ($ps_exit_status, $ps_output) = run_command("ps -o
pid=,cmd= @locking_pids", 1);
+ # if (defined($ps_output) && !grep(/(ps:)/, @$ps_output))
{
+ # notify($ERRORS{'DEBUG'}, 0, "file is locked by
another process: @locking_pids\n" . join("\n", @$ps_output));
+ # }
+ # else {
+ # notify($ERRORS{'DEBUG'}, 0, "file is locked by
another process: @locking_pids");
+ # }
+ # return;
+ # }
+ #}
+ #else {
+ # notify($ERRORS{'DEBUG'}, 0, "unable to determine PIDs of
processes which prevented an exclusive lock to be obtained on $file_path, lock
may have been released before lsof command was executed");
+ #}
return;
}
#/////////////////////////////////////////////////////////////////////////////
-
-=head2 get_lockfile_owning_pid
-
- Parameters : $file_path
- Returns : integer
- Description : Runs lsof to determine if a process has an exclusive lock on the
- lockfile.
-
-=cut
-
-sub get_lockfile_owning_pid {
- my $self = shift;
- unless (ref($self) && $self->isa('VCL::Module')) {
- notify($ERRORS{'CRITICAL'}, 0, "subroutine was called as a
function, it must be called as a class method");
- return;
- }
-
- # Get the file path argument
- my ($file_path) = @_;
- if (!$file_path) {
- notify($ERRORS{'WARNING'}, 0, "file path argument was not
supplied");
- return;
- }
-
- # Run lsof to determine which process is locking the file
- my ($exit_status, $output) = $self->mn_os->execute("/usr/sbin/lsof -Fp
$file_path", 0, 10);
- if (!defined($output)) {
- notify($ERRORS{'WARNING'}, 0, "failed to run lsof command to
determine which process is locking the file: $file_path");
- return;
- }
- elsif (grep(/no such file/i, @$output)) {
- notify($ERRORS{'WARNING'}, 0, "lsof command reports that the
file does not exist: $file_path");
- return;
- }
-
- # Parse the lsof output to determine the PID
- my @locking_pids = map { /^p(\d+)/ } @$output;
- my $locking_pid_count = scalar(@locking_pids);
- if (@locking_pids) {
- notify($ERRORS{'DEBUG'}, 0, "$file_path is locked by process" .
($locking_pid_count == 1 ? '' : 'es') . ": @locking_pids");
- return @locking_pids;
- }
- elsif (grep(/\w/, @$output)) {
- notify($ERRORS{'WARNING'}, 0, "failed to determine owning PID
of lockfile: $file_path, unable to determine PIDs from lsof output\n:" .
join("\n", @$output));
- return;
- }
- else {
- notify($ERRORS{'DEBUG'}, 0, "file is not locked: $file_path");
- return ();
- }
-}
+#
+#=head2 get_lockfile_owning_pid
+#
+# Parameters : $file_path
+# Returns : integer
+# Description : Runs lsof to determine if a process has an exclusive lock on
the
+# lockfile.
+#
+#=cut
+#
+#sub get_lockfile_owning_pid {
+# my $self = shift;
+# unless (ref($self) && $self->isa('VCL::Module')) {
+# notify($ERRORS{'CRITICAL'}, 0, "subroutine was called as a
function, it must be called as a class method");
+# return;
+# }
+#
+# # Get the file path argument
+# my ($file_path) = @_;
+# if (!$file_path) {
+# notify($ERRORS{'WARNING'}, 0, "file path argument was not
supplied");
+# return;
+# }
+#
+# # Run lsof to determine which process is locking the file
+# #my ($exit_status, $output) = $self->mn_os->execute("/usr/sbin/lsof -S
2 -O -Fp $file_path", 1, 10);
+# my ($exit_status, $output) = $self->mn_os->execute("/usr/sbin/lsof -Fp
$file_path", 0, 10);
+# if (!defined($output)) {
+# notify($ERRORS{'WARNING'}, 0, "failed to run lsof command to
determine which process is locking the file: $file_path");
+# return;
+# }
+# elsif (grep(/no such file/i, @$output)) {
+# notify($ERRORS{'WARNING'}, 0, "lsof command reports that the
file does not exist: $file_path");
+# return;
+# }
+#
+# # Parse the lsof output to determine the PID
+# my @locking_pids = map { /^p(\d+)/ } @$output;
+# my $locking_pid_count = scalar(@locking_pids);
+# if (@locking_pids) {
+# notify($ERRORS{'DEBUG'}, 0, "$file_path is locked by process" .
($locking_pid_count == 1 ? '' : 'es') . ": @locking_pids");
+# return @locking_pids;
+# }
+# elsif (grep(/\w/, @$output)) {
+# notify($ERRORS{'WARNING'}, 0, "failed to determine owning PID
of lockfile: $file_path, unable to determine PIDs from lsof output\n:" .
join("\n", @$output));
+# return;
+# }
+# else {
+# notify($ERRORS{'DEBUG'}, 0, "file is not locked: $file_path");
+# return ();
+# }
+#}
#/////////////////////////////////////////////////////////////////////////////
@@ -314,6 +316,10 @@ sub release_lockfile {
notify($ERRORS{'WARNING'}, 0, "file is not opened: $file_path");
}
+ if (!flock($file_handle, LOCK_UN)) {
+ notify($ERRORS{'WARNING'}, 0, "failed to unlock file:
$file_path, reason: $!");
+ }
+
# Close the file
if (!close($file_handle)) {
notify($ERRORS{'WARNING'}, 0, "failed to close file:
$file_path, reason: $!");
