cgroup: use version returned from get_path()

Instead of deciding via `cgroup_mode()` use the version we
get from get_path().

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

diff --git a/src/PVE/LXC/CGroup.pm b/src/PVE/LXC/CGroup.pm
index 7f232033821e71613b98b35d4e4647bee7a73b0e..780b0e5f3fc100f82320131ca18171071c2fe2ff 100644 (file)
--- a/src/PVE/LXC/CGroup.pm
+++ b/src/PVE/LXC/CGroup.pm
@@ -269,26 +269,28 @@ sub get_io_stats {
        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} += $b;
-               }
+    # With cgroupv1 we have a 'blkio' controller, with cgroupv2 it's just 'io':
+    my ($path, $ver) = $self->get_any_path('io', 'blkio');
+    if (!defined($path)) {
+       # container not running
+       return undef;
+    } elsif ($ver == 2) {
+       # 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'))) {
+
+       return $res;
+    } elsif ($ver == 1) {
        # cgroupv1 environment:
        my $io = file_get_contents("$path/blkio.throttle.io_service_bytes_recursive");
        foreach my $line (split(/\n/, $io)) {
@@ -297,12 +299,14 @@ sub get_io_stats {
                $res->{diskwrite} += $bytes if $type eq 'Write';
            }
        }
+
+       return $res;
     } else {
-       # container not running
-       return undef;
+       die "bad cgroup version: $ver\n";
     }
 
-    return $res;
+    # container not running
+    return undef;
 }
 
 # Read utime and stime for this container from the cpuacct cgroup.
@@ -315,21 +319,20 @@ sub get_cpu_stat {
        stime => 0,
     };
 
-    if (cgroup_mode() == 2) {
-       if (defined(my $path = $self->get_path('cpu'))) {
-           my $data = eval { file_get_contents("$path/cpu.stat") };
+    my ($path, $ver) = $self->get_any_path('cpuacct', 'cpu');
+    if (!defined($path)) {
+       # container not running
+       return undef;
+    } elsif ($ver == 2) {
+       my $data = eval { file_get_contents("$path/cpu.stat") };
 
-           # or no io controller available:
-           return undef if !defined($data);
+       # or no io controller available:
+       return undef if !defined($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'))) {
+       $data = parse_flat_keyed_file($data);
+       $res->{utime} = int($data->{user_usec} / 1000);
+       $res->{stime} = int($data->{system_usec} / 1000);
+    } elsif ($ver == 1) {
        # cgroupv1 environment:
        my $clock_ticks = POSIX::sysconf(&POSIX::_SC_CLK_TCK);
        my $clk_to_usec = 1000 / $clock_ticks;
@@ -338,8 +341,7 @@ sub get_cpu_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;
+       die "bad cgroup version: $ver\n";
     }
 
     return $res;
@@ -354,23 +356,22 @@ sub get_memory_stat {
        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");
+    my ($path, $ver) = $self->get_path('memory');
+    if (!defined($path)) {
+       # container most likely isn't running
+       return undef;
+    } elsif ($ver == 2) {
+       my $mem = file_get_contents("$path/memory.current");
+       my $swap = file_get_contents("$path/memory.swap.current");
 
-           chomp ($mem, $swap);
+       chomp ($mem, $swap);
 
-           # FIXME: For the cgv1 equivalent of `total_cache` we may need to sum up
-           # the values in `memory.stat`...
+       # 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'))) {
+       $res->{mem} = $mem;
+       $res->{swap} = $swap;
+    } elsif ($ver == 1) {
        # cgroupv1 environment:
        my $stat = parse_flat_keyed_file(file_get_contents("$path/memory.stat"));
        my $mem = file_get_contents("$path/memory.usage_in_bytes");
@@ -380,8 +381,7 @@ sub get_memory_stat {
        $res->{mem} = $mem - $stat->{total_cache};
        $res->{swap} = $memsw - $mem;
     } else {
-       # container most likely isn't running
-       return undef;
+       die "bad cgroup version: $ver\n";
     }
 
     return $res;
@@ -393,15 +393,15 @@ sub get_memory_stat {
 sub change_memory_limit {
     my ($self, $mem_bytes, $swap_bytes) = @_;
 
-    if (cgroup_mode() == 2) {
-       if (defined(my $path = $self->get_path('memory'))) {
-           PVE::ProcFSTools::write_proc_entry("$path/memory.swap.max", $swap_bytes)
-               if defined($swap_bytes);
-           PVE::ProcFSTools::write_proc_entry("$path/memory.max", $mem_bytes)
-               if defined($mem_bytes);
-           return 1;
-       }
-    } elsif (defined(my $path = $self->get_path('memory'))) {
+    my ($path, $ver) = $self->get_path('memory');
+    if (!defined($path)) {
+       die "trying to change memory cgroup values: container not running\n";
+    } elsif ($ver == 2) {
+       PVE::ProcFSTools::write_proc_entry("$path/memory.swap.max", $swap_bytes)
+           if defined($swap_bytes);
+       PVE::ProcFSTools::write_proc_entry("$path/memory.max", $mem_bytes)
+           if defined($mem_bytes);
+    } elsif ($ver == 1) {
        # With cgroupv1 we cannot control memory and swap limits separately.
        # This also means that since the two values aren't independent, we need to handle
        # growing and shrinking separately.
@@ -426,10 +426,12 @@ sub change_memory_limit {
            PVE::ProcFSTools::write_proc_entry($path_mem, $mem_bytes);
            PVE::ProcFSTools::write_proc_entry($path_memsw, $memsw_bytes);
        }
-       return 1;
+    } else {
+       die "bad cgroup version: $ver\n";
     }
 
-    die "trying to change memory cgroup values: container not running\n";
+    # return a truth value
+    return 1;
 }
 
 # Change the cpu quota for a container.
@@ -440,28 +442,30 @@ sub change_cpu_quota {
 
     die "quota without period not allowed\n" if !defined($period) && defined($quota);
 
-    if (cgroup_mode() == 2) {
-       if (defined(my $path = $self->get_path('cpu'))) {
-           # cgroupv2 environment, an undefined (unlimited) quota is defined as "max"
-           # in this interface:
-           $quota //= 'max'; # unlimited
-           if (defined($quota)) {
-               PVE::ProcFSTools::write_proc_entry("$path/cpu.max", "$quota $period");
-           } else {
-               # we're allowed to only write the quota:
-               PVE::ProcFSTools::write_proc_entry("$path/cpu.max", 'max');
-           }
-           return 1;
+    my ($path, $ver) = $self->get_path('memory');
+    if (!defined($path)) {
+       die "trying to change cpu quota cgroup values: container not running\n";
+    } elsif ($ver == 2) {
+       # cgroupv2 environment, an undefined (unlimited) quota is defined as "max"
+       # in this interface:
+       $quota //= 'max'; # unlimited
+       if (defined($quota)) {
+           PVE::ProcFSTools::write_proc_entry("$path/cpu.max", "$quota $period");
+       } else {
+           # we're allowed to only write the quota:
+           PVE::ProcFSTools::write_proc_entry("$path/cpu.max", 'max');
        }
-    } elsif (defined(my $path = $self->get_path('cpu'))) {
+    } elsif ($ver == 1) {
        $quota //= -1; # unlimited
        $period //= -1;
        PVE::ProcFSTools::write_proc_entry("$path/cpu.cfs_period_us", $period);
        PVE::ProcFSTools::write_proc_entry("$path/cpu.cfs_quota_us", $quota);
-       return 1;
+    } else {
+       die "bad cgroup version: $ver\n";
     }
 
-    die "trying to change cpu quota cgroup values: container not running\n";
+    # return a truth value
+    return 1;
 }
 
 # Change the cpu "shares" for a container.
@@ -480,22 +484,23 @@ sub change_cpu_quota {
 sub change_cpu_shares {
     my ($self, $shares, $cgroupv1_default) = @_;
 
-    if (cgroup_mode() == 2) {
-       if (defined(my $path = $self->get_path('cpu'))) {
-           # the cgroupv2 documentation defines the default to 100
-           $shares //= 100;
-           die "cpu weight (shares) must be in range [1, 10000]\n" if $shares < 1 || $shares > 10000;
-           PVE::ProcFSTools::write_proc_entry("$path/cpu.weight", $shares);
-           return 1;
-       }
+    my ($path, $ver) = $self->get_path('memory');
+    if (!defined($path)) {
+       die "trying to change cpu shares/weight cgroup values: container not running\n";
+    } elsif ($ver == 2) {
+       # the cgroupv2 documentation defines the default to 100
+       $shares //= 100;
+       die "cpu weight (shares) must be in range [1, 10000]\n" if $shares < 1 || $shares > 10000;
+       PVE::ProcFSTools::write_proc_entry("$path/cpu.weight", $shares);
     } elsif (defined(my $path = $self->get_path('cpu'))) {
        $shares //= 100;
        PVE::ProcFSTools::write_proc_entry("$path/cpu.shares", $shares // $cgroupv1_default);
-       return 1;
+    } else {
+       die "bad cgroup version: $ver\n";
     }
 
-    # container most likely isn't running
-    die "trying to change cpu shares/weight cgroup values: container not running\n";
+    # return a truth value
+    return 1;
 }
 
 1;