This commit separates the functionality of setting cgroup device
rules out of libct/cgroups to libct/cgroups/devices package. This
package, if imported, sets the function variables in libct/cgroups and
libct/cgroups/systemd, so that a cgroup manager can use those to manage
devices. If those function variables are nil (when libct/cgroups/devices
are not imported), a cgroup manager returns the ErrDevicesUnsupported
in case any device rules are set in Resources.
It also consolidates the code from libct/cgroups/ebpf and
libct/cgroups/ebpf/devicefilter into libct/cgroups/devices.
Moved some tests in libct/cg/sd that require device management to
libct/sd/devices.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
I have noticed that libct/cg/fs allocates 8K during init on every runc
execution:
> init github.com/opencontainers/runc/libcontainer/cgroups/fs @1.5 ms, 0.028 ms clock, 8512 bytes, 13 allocs
Apparently this is caused by global HugePageSizes variable init, which
is only used from GetStats (i.e. it is never used by runc itself).
Remove it, and use HugePageSizes() directly instead. Make it init-once,
so that GetStats (which, I guess, is periodically called by kubernetes)
does not re-read huge page sizes over and over.
This also removes 12 allocs and 8K from libct/cg/fs init section:
> $ time GODEBUG=inittrace=1 ./runc --help 2>&1 | grep cgroups/fs
> init github.com/opencontainers/runc/libcontainer/cgroups/fs @1.5 ms, 0.003 ms clock, 16 bytes, 1 allocs
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Since GetHugePageSize do not have any external users (checked by
sourcegraph), and no internal user ever uses its second return value
(the error), let's drop it.
2. Rename GetHugePageSize -> HugePageSizes (drop the Get prefix as per
Go guidelines, add suffix since we return many sizes).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Users would like to have the possibility to skip checks for their
tests the same way they are skipped within the tests in runc.
Not exposing this variable makes it very hard to test components
that use this library. To avoid copying-and-pasting the code
into outside projects this variable sould be exposed to the users.
Signed-off-by: Itamar Holder <iholder@redhat.com>
Currently the parent process of the container is moved to the right
cgroup v2 tree when systemd is using a hybrid model (last line with 0::):
$ runc --systemd-cgroup run myid
/ # cat /proc/self/cgroup
12:cpuset:/system.slice/runc-myid.scope
11:blkio:/system.slice/runc-myid.scope
10:devices:/system.slice/runc-myid.scope
9:hugetlb:/system.slice/runc-myid.scope
8:memory:/system.slice/runc-myid.scope
7:rdma:/
6:perf_event:/system.slice/runc-myid.scope
5:net_cls,net_prio:/system.slice/runc-myid.scope
4:freezer:/system.slice/runc-myid.scope
3:pids:/system.slice/runc-myid.scope
2:cpu,cpuacct:/system.slice/runc-myid.scope
1:name=systemd:/system.slice/runc-myid.scope
0::/system.slice/runc-myid.scope
However, if a second process is executed in the same container, it is
not moved to the right cgroup v2 tree:
$ runc exec myid /bin/sh -c 'cat /proc/self/cgroup'
12:cpuset:/system.slice/runc-myid.scope
11:blkio:/system.slice/runc-myid.scope
10:devices:/system.slice/runc-myid.scope
9:hugetlb:/system.slice/runc-myid.scope
8:memory:/system.slice/runc-myid.scope
7:rdma:/
6:perf_event:/system.slice/runc-myid.scope
5:net_cls,net_prio:/system.slice/runc-myid.scope
4:freezer:/system.slice/runc-myid.scope
3:pids:/system.slice/runc-myid.scope
2:cpu,cpuacct:/system.slice/runc-myid.scope
1:name=systemd:/system.slice/runc-myid.scope
0::/user.slice/user-1000.slice/session-8.scope
This commit makes that processes executed with exec are placed into the
right cgroup v2 tree. The implementation checks if systemd is using a
hybrid mode (by checking if cgroups v2 is mounted in
/sys/fs/cgroup/unified), if yes, the path of the cgroup v2 slice for
this container is saved into the cgroup path list.
The fs group driver has a similar issue, in this case none of the runc
run or runc exec commands put the process in the right cgroups v2. This
commit also fixes that.
Having the processes of the container in its own cgroup v2 is useful
for any BPF programs that rely on bpf_get_current_cgroup_id(), like
https://github.com/kinvolk/inspektor-gadget/ for instance.
[@kolyshkin: rebased]
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
It is assumed that m.config is not nil, so these checks are redundant
(in case it is nil, NewManager panics and this code is unreachable).
Note that cgroups/manager.New checks that config is not nil.
Remove them.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This is already documented but I guess more explanations (in particular,
why the path is being removed from paths) won't hurt.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Separate path initialization logic from Apply to initPaths,
and call initPaths from NewManager, so:
- we can error out early (in NewManager rather than Apply);
- always have m.paths available (e.g. in Destroy or Exists).
- do not unnecessarily call subsysPath from Apply in case
the paths were already provided.
2. Add a check for non-nil cgroups.Resources to NewManager,
since initPaths, as well as some controller's Apply methods,
need it.
3. Move cgroups.Resources.Unified check from Apply to NewManager,
so we can error out early (same check exists in Set).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Make Rootless and Systemd flags part of config.Cgroups.
2. Make all cgroup managers (not just fs2) return error (so it can do
more initialization -- added by the following commits).
3. Replace complicated cgroup manager instantiation in factory_linux
by a single (and simple) libcontainer/cgroups/manager.New() function.
4. getUnifiedPath is simplified to check that only a single path is
supplied (rather than checking that other paths, if supplied,
are the same).
[v2: can't -> cannot]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Dismantle and remove struct cgroupData. It contained three unrelated
entities (cgroup paths, pid, and resources), and made the code
harder to read. Most importantly, though, it is not needed.
Now, subsystems' Apply methods take path, resources, and pid.
To a reviewer -- the core of the changes is in fs.go and paths.go,
the rest of it is adapting to the new signatures and related test
changes.
2. Dismantle and remove struct cgroupTestUtil. This is a followup
to the previous item -- since cgroupData is gone, there is nothing
to hold in cgroupTestUtil. The change itself is very small (see
util_test.go), but this patch is big because of it -- mostly
because we had to replace helper.cgroup.Resources with
&config.Resources{}.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
In case c.Path is set, c.Name and c.Parent are not used, and so
calls to utils.CleanPath are entirely unnecessary. Move them to
inside of the "if" statement body.
Get rid of the intermediate cgPath variable, it is not needed.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Now fs.go is not very readable as its public API functions are
intermixed with internal stuff about getting cgroup paths.
Move that out to paths.go, without changing any code.
Same for the tests -- move paths-related tests to paths_test.go.
This commit is separate to make the review easier.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
These are not needed as these packages (libcontainer/cgroups,
libcontainer/cgroups/fs, and libcontainer/cgroups/systemd) can
not be built under non-linux anyway (for various reasons).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Only some libcontainer packages can be built on non-linux platforms
(not that it make sense, but at least go build succeeds). Let's call
these "good" packages.
For all other packages (i.e. ones that fail to build with GOOS other
than linux), it does not make sense to have linux build tag (as they
are broken already, and thus are not and can not be used on anything
other than Linux).
Remove linux build tag for all non-"good" packages.
This was mostly done by the following script, with just a few manual
fixes on top.
function list_good_pkgs() {
for pkg in $(find . -type d -print); do
GOOS=freebsd go build $pkg 2>/dev/null \
&& GOOS=solaris go build $pkg 2>/dev/null \
&& echo $pkg
done | sed -e 's|^./||' | tr '\n' '|' | sed -e 's/|$//'
}
function remove_tag() {
sed -i -e '\|^// +build linux$|d' $1
go fmt $1
}
SKIP="^("$(list_good_pkgs)")"
for f in $(git ls-files . | grep .go$); do
if echo $f | grep -qE "$SKIP"; then
echo skip $f
continue
fi
echo proc $f
remove_tag $f
done
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
As reported in issue 3084, sometimes setting CPU quota period fails
when a new period is lower and a parent cgroup has CPU quota limit set.
This happens as in cgroup v1 the quota and the period can not be set
together (this is fixed in v2), and since the period is being set first,
new_limit = old_quota/new_period may be higher than the parent cgroup
limit.
The fix is to retry setting the period after the quota, to cover all
possible scenarios.
Add a test case to cover a regression caused by an earlier version of
this patch (ignoring a failure of setting invalid period when quota is
not set).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The two exceptions I had to add to codespellrc are:
- CLOS (used by intelrtd);
- creat (syscall name used in tests/integration/testdata/seccomp_*.json).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This was initially added by commits 41d9d26513 and 4a8f0b4db4,
apparently to implement docker run --cgroup container:ID, which was
never merged. Therefore, this code is not and was never used.
It needs to be removed mainly because having it makes it much harder to
understand how cgroup manager works (because with this in place we have
not one or two but three sets of cgroup paths to think about).
Note if the paths are known and there is a need to add a PID to existing
cgroup, cgroup manager is not needed at all -- something like
cgroups.WriteCgroupProc or cgroups.EnterPid is sufficient (and the
latter is what runc exec uses in (*setnsProcess).start).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
If a control group is frozen, all its descendants will report FROZEN
in freezer.state cgroup file.
OTOH cgroup v2 cgroup.freeze is not reporting the cgroup as frozen
unless it is frozen directly (i.e. not via an ancestor).
Fix the discrepancy between v1 and v2 drivers behavior by
looking into freezer.self_freezing cgroup file, which, according
to kernel documentation, will show 1 iff the cgroup was frozen directly.
Co-authored-by: Kir Kolyshkin <kolyshkin@gmail.com>
Signed-off-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Errors from unix.* are always bare and thus can be used directly.
Add //nolint:errorlint annotation to ignore errors such as these:
libcontainer/system/xattrs_linux.go:18:7: comparing with == will fail on wrapped errors. Use errors.Is to check for a specific error (errorlint)
case errno == unix.ERANGE:
^
libcontainer/container_linux.go:1259:9: comparing with != will fail on wrapped errors. Use errors.Is to check for a specific error (errorlint)
if e != unix.EINVAL {
^
libcontainer/rootfs_linux.go:919:7: comparing with != will fail on wrapped errors. Use errors.Is to check for a specific error (errorlint)
if err != unix.EINVAL && err != unix.EPERM {
^
libcontainer/rootfs_linux.go:1002:4: switch on an error will fail on wrapped errors. Use errors.Is to check for specific errors (errorlint)
switch err {
^
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This builds on top of recently introduced fscommon.ParseError.
Errors returned from parsers (mostly ones used by GetStats()) are all
different, and many are incomplete. For example, in many cases errors
from strconv.ParseUint are returned as is, meaning there is no context
telling which file we were reading. Similarly, errors from
fscommon.ParseKeyValue should be wrapped to add more context.
Same is true for scanner.Err().
One special case that repeats a few times is "malformed line: xxx".
Add and use a helper for that to simplify things.
OTOH, errors from fscommon.GetCgroup* do have enough context and there
is no need to wrap them.
Fix all the above.
While at it, add a missing scanner.Err() check.
[v2: use parseError not ParseError]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Do not wrap errors returned from fscommon.GetCgroupParamUint -- those
errors already have enough context.
2. Instead of parsing "max" ourselves, use GetCgroupParamUint which does
it, and then convert MaxUint64 to 0 (we do it historically since
commit 087b953dc5, and while using MaxUint64 as is seems fine,
there may be some existing users who rely on the old behavior).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The error from fscommon.GetCgroup* already contains the file name and so
on, so there's no need to wrap it.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
For per-device weight, you can set weight and/or leaf weight.
The problem is, with the recent fix to use BFQ on cgroup v1,
if per-device weights are set, the code tries to set device
weight to blkio.bfq.weight, and the leaf weight to
blkio.leaf_weight_device. The latter file does not exist on
kernels v5.0, meaning one can not set any per-device weights
at all.
The fix is to only set weights if they are non-zero (i.e. set).
The test case will come in a following commit.
Fixes: 6339d8a0dd
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This is a better place as cgroups itself is using these.
Should help with moving more stuff common in between fs and fs2 to
fscommon.
Looks big, but this is just moving the code around:
fscommon/{fscommon,open}.go -> cgroups/file.go
fscommon/fscommon_test.go -> cgroups/file_test.go
and fixes for TestMode moved to a different package.
There's no functional change.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
- Update the blkio cgroup to support the BFQ I/O Scheduler, that has
replaced CFQ in the Linux kernel.
- BFQ is controlled through blkio.bfq.weight[_device] instead of
CFQ's blkio.weight[_device] in cgroups v1.
- BFQ does not support blkio.leaf_weight[_device], so that behavior
remains untouched.
- Do not change behavior on legacy CFQ systems.
- Enable using blkio weights on BFQ systems.
Signed-off-by: Antti Kervinen <antti.kervinen@intel.com>
These functions are called from multiple places,
and if t.Helper() is not used, the context is not clear.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
gofumpt (mvdan.cc/gofumpt) is a fork of gofmt with stricter rules.
Brought to you by
git ls-files \*.go | grep -v ^vendor/ | xargs gofumpt -s -w
Looking at the diff, all these changes make sense.
Also, replace gofmt with gofumpt in golangci.yml.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Most of these were false positives or cases where we want to ignore the
lint, but the change to the BPF generation is actually useful.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
I hate to keep adding those kludges, but lately TestFreeze (and
TestSystemdFreeze) from libcontainer/integration fails a lot. The
failure comes and goes, and is probably this is caused by a slow host
allocated for the test, and a slow VM on top of it.
To remediate, add a small sleep on every 25th iteration in between
asking the kernel to freeze and checking its status.
In the worst case scenario (failure to freeze), this adds about 0.4 ms
(40 x 10 us) to the duration of the call.
It is hard to measure how this affects CI as GHA plays a roulette when
allocating a node to run the test on, but it seems to help. With
additional debug info, I saw somewhat frequent "frozen after 24 retries"
or "frozen after 49 retries", meaning it succeeded right after the added
sleep.
While at it, rewrite/improve the comments.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
A cgroup manager's Set method sets cgroup resources, but historically
it was accepting configs.Cgroups.
Refactor it to accept resources only. This is an improvement from the
API point of view, as the method can not change cgroup configuration
(such as path to the cgroup etc), it can only set (modify) its
resources/limits.
This also lays the foundation for complicated resource updates, as now
Set has two sets of resources -- the one that was previously specified
during cgroup manager creation (or the previous Set), and the one passed
in the argument, so it could deduce the difference between these. This
is a long term goal though.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Commit 88e8350de2, among the other things, replaced filepath.Join with
securejoin.SecureJoin for both reads and writes to cgroupfs.
Commits e76ac1c054 and 31f0f5b7e0 switched more code to use
fscommon.ReadFile (and thus securejoin). Commit 0228226e6d introduced
fscommon.OpenFile (which uses securejoin as the fallback if openat2(2)
is not available, which is the case for older kernels), and commit
c95e69007c switched most of cgroup/fs[2] code to use it.
As a result, fs.GetStats() method became noticeable slower, mostly due
to securejoin calling os.Lstat and filepath.Clean.
Using securejoin as a security measure for cgroupfs files is
not well justified, as cgroupfs do not contain symlinks, and none of the
code using it have uncleaned paths. In particular, fs/fs2/systemd
managers do check and sanitize their paths.
This commit modifies the code to not use securejoin. Instead, it checks
that the opened file is indeed on cgroupfs.
Using BenchmarkGetStats on a CentOS 8 VM, I see the following
improvement:
Before:
> BenchmarkGetStats-8 8376 625135 ns/op
After:
> BenchmarkGetStats-8 12226 485015 ns/op
An intermediate version, with no fstatfs to check fstype:
> BenchmarkGetStats-8 13162 452281 ns/op
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Kir Kolyshkin