# container (via the command socket), reading and writing cgroup values, and
# handling cgroup v1 & v2 differences.
#
-# Note that the long term plan is to have resource manage functions intead of
+# Note that the long term plan is to have resource manage functions instead of
# dealing with cgroup files on the outside.
package PVE::LXC::CGroup;
use strict;
use warnings;
-use POSIX qw();
-
-use PVE::Tools qw(
- file_get_contents
- file_read_firstline
-);
-
use PVE::LXC::Command;
+use PVE::CGroup;
+use base('PVE::CGroup');
-# We don't want to do a command socket round trip for every cgroup read/write,
-# so any cgroup function needs to have the container's path cached, so this
-# package has to be instantiated.
-#
-# LXC keeps separate paths by controller (although they're normally all the
-# same, in our # case anyway), so we cache them by controller as well.
-sub new {
- my ($class, $vmid) = @_;
-
- my $self = { vmid => $vmid };
-
- return bless $self, $class;
-}
-
-my $CPUSET_BASE = undef;
-# Find the cpuset cgroup controller.
-#
-# This is a function, not a method!
-sub cpuset_controller_path() {
- if (!defined($CPUSET_BASE)) {
- my $CPUSET_PATHS = [
- # legacy cpuset cgroup:
- ['/sys/fs/cgroup/cpuset', 'cpuset.effective_cpus'],
- # pure cgroupv2 environment:
- ['/sys/fs/cgroup', 'cpuset.cpus.effective'],
- # hybrid, with cpuset moved to cgroupv2
- ['/sys/fs/cgroup/unified', 'cpuset.cpus.effective'],
- ];
-
- my ($result) = grep { -f "$_->[0]/$_->[1]" } @$CPUSET_PATHS;
- die "failed to find cpuset controller\n" if !defined($result);
-
- $CPUSET_BASE = $result->[0];
- }
-
- return $CPUSET_BASE;
-}
-
-my $CGROUP_MODE = undef;
-# Figure out which cgroup mode we're operating under:
-#
-# Returns 1 if cgroupv1 controllers exist (hybrid or legacy mode), and 2 in a
-# cgroupv2-only environment.
-#
-# This is a function, not a method!
-sub cgroup_mode() {
- if (!defined($CGROUP_MODE)) {
- my ($v1, $v2) = PVE::LXC::get_cgroup_subsystems();
- if (keys %$v1) {
- # hybrid or legacy mode
- $CGROUP_MODE = 1;
- } elsif ($v2) {
- $CGROUP_MODE = 2;
- }
- }
-
- die "unknown cgroup mode\n" if !defined($CGROUP_MODE);
- return $CGROUP_MODE;
-}
# Get a subdirectory (without the cgroup mount point) for a controller.
#
# (`cgroup.controllers` file) as list of controllers for the unified hierarchy,
# so this returns a result when a `controller` is provided even when using
# a pure cgroupv2 setup.
-my sub get_subdir {
+sub get_subdir {
my ($self, $controller, $limiting) = @_;
my $entry_name = $controller || 'unified';
return $path;
}
-# Get a path for a controller.
-#
-# `$controller` may be `undef`, see get_subdir above for details.
-sub get_path {
- my ($self, $controller) = @_;
-
- my $path = get_subdir($self, $controller)
- or return undef;
-
- # The main mount point we currenlty assume to be in a standard location.
- return "/sys/fs/cgroup/$path" if cgroup_mode() == 2;
- return "/sys/fs/cgroup/unified/$path" if !defined($controller);
- return "/sys/fs/cgroup/$controller/$path";
-}
-
-# Parse a 'Nested keyed' file:
-#
-# See kernel documentation `admin-guide/cgroup-v2.rst` 4.1.
-my sub parse_nested_keyed_file($) {
- my ($data) = @_;
- my $res = {};
- foreach my $line (split(/\n/, $data)) {
- my ($key, @values) = split(/\s+/, $line);
-
- my $d = ($res->{$key} = {});
-
- foreach my $value (@values) {
- if (my ($key, $value) = ($value =~ /^([^=]+)=(.*)$/)) {
- $d->{$key} = $value;
- } else {
- warn "bad key=value pair in nested keyed file\n";
- }
- }
- }
- return $res;
-}
-
-# Parse a 'Flat keyed' file:
-#
-# See kernel documentation `admin-guide/cgroup-v2.rst` 4.1.
-my sub parse_flat_keyed_file($) {
- my ($data) = @_;
- my $res = {};
- foreach my $line (split(/\n/, $data)) {
- if (my ($key, $value) = ($line =~ /^(\S+)\s+(.*)$/)) {
- $res->{$key} = $value;
- } else {
- warn "bad 'key value' pair in flat keyed file\n";
- }
- }
- return $res;
-}
-
-# Parse out 'diskread' and 'diskwrite' values from I/O stats for this container.
-sub get_io_stats {
- my ($self) = @_;
-
- my $res = {
- diskread => 0,
- diskwrite => 0,
- };
-
- if (cgroup_mode() == 2) {
- if (defined(my $path = $self->get_path('io'))) {
- # cgroupv2 environment, io controller enabled
- my $io_stat = file_get_contents("$path/io.stat");
-
- my $data = parse_nested_keyed_file($io_stat);
- foreach my $dev (keys %$data) {
- my $dev = $data->{$dev};
- if (my $b = $dev->{rbytes}) {
- $res->{diskread} += $b;
- }
- if (my $b = $dev->{wbytes}) {
- $res->{diskread} += $b;
- }
- }
- } else {
- # io controller not enabled or container not running
- return undef;
- }
- } elsif (defined(my $path = $self->get_path('blkio'))) {
- # cgroupv1 environment:
- my $io = file_get_contents("$path/blkio.throttle.io_service_bytes_recursive");
- foreach my $line (split(/\n/, $io)) {
- if (my ($type, $bytes) = ($line =~ /^\d+:\d+\s+(Read|Write)\s+(\d+)$/)) {
- $res->{diskread} += $bytes if $type eq 'Read';
- $res->{diskwrite} += $bytes if $type eq 'Write';
- }
- }
- } else {
- # container not running
- return undef;
- }
-
- return $res;
-}
-
-# Read utime and stime for this container from the cpuacct cgroup.
-# Values are in milliseconds!
-sub get_cpu_stat {
- my ($self) = @_;
-
- my $res = {
- utime => 0,
- stime => 0,
- };
-
- if (cgroup_mode() == 2) {
- if (defined(my $path = $self->get_path('cpu'))) {
- my $data = eval { file_get_contents("$path/cpu.stat") };
-
- # or no io controller available:
- return undef if !defined($data);
-
- $data = parse_flat_keyed_file($data);
- $res->{utime} = int($data->{user_usec} / 1000);
- $res->{stime} = int($data->{system_usec} / 1000);
- } else {
- # memory controller not enabled or container not running
- return undef;
- }
- } elsif (defined(my $path = $self->get_path('cpuacct'))) {
- # cgroupv1 environment:
- my $clock_ticks = POSIX::sysconf(&POSIX::_SC_CLK_TCK);
- my $clk_to_usec = 1000 / $clock_ticks;
-
- my $data = parse_flat_keyed_file(file_get_contents("$path/cpuacct.stat"));
- $res->{utime} = int($data->{user} * $clk_to_usec);
- $res->{stime} = int($data->{system} * $clk_to_usec);
- } else {
- # container most likely isn't running
- return undef;
- }
-
- return $res;
-}
-
-# Parse some memory data from `memory.stat`
-sub get_memory_stat {
- my ($self) = @_;
-
- my $res = {
- mem => 0,
- swap => 0,
- };
-
- if (cgroup_mode() == 2) {
- if (defined(my $path = $self->get_path('memory'))) {
- my $mem = file_get_contents("$path/memory.current");
- my $swap = file_get_contents("$path/memory.swap.current");
-
- chomp ($mem, $swap);
-
- # FIXME: For the cgv1 equivalent of `total_cache` we may need to sum up
- # the values in `memory.stat`...
-
- $res->{mem} = $mem;
- $res->{swap} = $swap;
- } else {
- # memory controller not enabled or container not running
- return undef;
- }
- } elsif (defined(my $path = $self->get_path('memory'))) {
- # cgroupv1 environment:
- my $stat = parse_flat_keyed_file(file_get_contents("$path/memory.stat"));
- my $mem = file_get_contents("$path/memory.usage_in_bytes");
- my $memsw = file_get_contents("$path/memory.memsw.usage_in_bytes");
- chomp ($mem, $memsw);
-
- $res->{mem} = $mem - $stat->{total_cache};
- $res->{swap} = $memsw - $mem;
- } else {
- # container most likely isn't running
- return undef;
- }
-
- return $res;
-}
-
1;
projects / pve-container.git / blobdiff