Since Go 1.19, godoc recognizes lists, code blocks, headings etc. It
also reformats the sources making it more apparent that these features
are used.
Fix a few places where it misinterpreted the formatting (such as
indented vs unindented), and format the result using the gofumpt
from HEAD, which already incorporates gofmt 1.19 changes.
Some more fixes (and enhancements) might be required.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
In case statfs("/sys/fs/cgroup/unified") fails with any error other
than ENOENT, current code panics. As IsCgroup2HybridMode is called from
libcontainer/cgroups/fs's init function, this means that any user of
libcontainer may panic during initialization, which is ugly.
Avoid panicking; instead, do not enable hybrid hierarchy support and
report the error (under debug level, not to confuse anyone).
Basically, replace the panic with "turn off hybrid mode support"
(which makes total sense since we were unable to statfs its root).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Instead of distinguishing between errors and warnings, let's treat all
errors as warnings, thus simplifying the code. This changes the
function behaviour for input like hugepages-BadNumberKb --
previously, the error from Atoi("BadNumber") was considered fatal,
now it's just another warnings.
2. Move the warning logging to HugePageSizes, thus simplifying the test
case, which no longer needs to read what logrus writes. Note that we
do not want to log all the warnings (as chances are very low we'll
get any, and if we do this means the code need to be updated), only
the first one.
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>
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>
No need to add a file name to the error messages, as errors from
OpenFile and (*os.File).Write both contain the file name already.
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>
Since every cgroup directory is guaranteed to have cgroup.procs file,
we don't have to do filename comparison in GetAllPids() and just read
cgroup.procs in every directory.
While at it, switch readProcsFile to use our own OpenFile.
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 should result in no change when the error is printed, but make the
errors returned unwrappable, meaning errors.As and errors.Is will work.
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>
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>
Moving these utilities to a separate package, so that consumers of this
package don't have to pull in the whole "system" package.
Looking at uses of these utilities (outside of runc itself);
`RunningInUserNS()` is used by [various external consumers][1],
so adding a "Deprecated" alias for this.
[1]: https://grep.app/search?current=2&q=.RunningInUserNS
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
if bfq is not loaded, then io.bfq.weight is not available. io.weight
should always be available and is the next best equivalent thing.
Signed-off-by: Daniel Dao <dqminh89@gmail.com>
bfq weight controller (i.e. io.bfq.weight if present) is still using the
same bfq weight scheme (i.e 1->1000, see [1].) Unfortunately the
documentation for this was wrong, and only fixed recently [2].
Therefore, if we map blkio weight to io.bfq.weight, there's no need to
do any conversion. Otherwise, we will try to write invalid value which
results in error such as:
```
time="2021-02-03T14:55:30Z" level=error msg="container_linux.go:367: starting container process caused: process_linux.go:495: container init caused: process_linux.go:458: setting cgroup config for procHooks process caused: failed to write \"7475\": write /sys/fs/cgroup/runc-cgroups-integration-test/test-cgroup/io.bfq.weight: numerical result out of range"
```
[1] https://github.com/torvalds/linux/blob/master/Documentation/block/bfq-iosched.rst
[2] https://github.com/torvalds/linux/commit/65752aef0a407e1ef17ec78a7fc31ba4e0b360f9
Signed-off-by: Daniel Dao <dqminh89@gmail.com>
> libcontainer/cgroups/utils.go:282:4: SA4006: this value of `paths` is never used (staticcheck)
> paths = make(map[string]string)
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This is a function to convert huge page sizes (obtained by reading
/sys/kernel/mm/hugepages directory entries) to strings user for hugetlb
cgroup controller resource files. Those strings are when used to get the
hugetlb resource statistics.
This function used external library, floating point numbers, and can
(theoretically) produce invalid values, since the kernel only uses KB,
MB, and GB suffixes.
Rewrite it to produce the same strings as used in the kernel (see [1]).
As a result, it's also faster, more future-proof (entries that do not
start with "hugepages-" and/or incorrect suffix are skipped), and does
more input sanity checks. As a side effect, libcontainer no longer
depends on docker/go-units.
While at it, add more test cases.
Before:
BenchmarkGetHugePageSize-8 187452 6265 ns/op
BenchmarkGetHugePageSizeImpl-8 396769 2998 ns/op
After:
BenchmarkGetHugePageSize-8 222898 4554 ns/op
BenchmarkGetHugePageSizeImpl-8 4738924 241 ns/op
NOTE on removing HugePageSizeUnitList -- this was added by commit
6f77e35da and was used by kubernetes code in [2], which was later
superceded by [3], so there are (hopefully) no external users.
If there are any, they should not be doing that.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/mm/hugetlb_cgroup.c?id=eff48ddeab782e35e58ccc8853f7386bbae9dec4#n574
[2] https://github.com/kubernetes/kubernetes/pull/78495
[3] https://github.com/kubernetes/kubernetes/pull/84154
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
ioutil.ReadFile does a stat() on every entry and returns a slice of
os.Stat structures. What we need here is just a file name.
This change both simplifies and speeds up the code a bit.
Before:
BenchmarkGetHugePageSize-8 115213 9400 ns/op
After:
BenchmarkGetHugePageSize-8 190326 6187 ns/op
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Using os.RemoveAll has the following two issues:
1. it tries to remove all files, which does not make sense for cgroups;
2. it tries rm(2) which fails to directories, and then rmdir(2).
Let's reuse our RemovePath instead, and add warnings and errors logging.
PS I am somewhat hesitant to remove the weird checking my means of stat,
as it might break something. Unfortunately, neither commit 6feb7bda04
nor the PR it contains [1] do not explain what kind of weird errors were
seen from os.RemoveAll. Most probably our code won't return any bogus
errors, but let's keep the old code to be on the safe side.
[1] https://github.com/docker-archive/libcontainer/pull/308
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
RemovePaths() deletes elements from the paths map for paths that has
been successfully removed.
Although, it does not empty the map itself (which is needed that AFAIK
Go garbage collector does not shrink the map), but all its callers do.
Move this operation from callers to RemovePaths.
No functional change, except the old map should be garbage collected now.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Not sure why but the errors from scanner were ignored. Such errors
can happen if open(2) has succeeded but the subsequent read(2) fails.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
In most project, "utils" is a big mess, and this is not an exception.
Try to clean it up a bit by moving cgroup v1 specific code to a separate
source file.
There are no code changes in this commit, just moving it from one file
to another.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This function is cgroupv1-specific, is only used once, and its name
is very close to the name of another function, FindCgroupMountpoint.
Inline it into the (only) caller.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This function is only called from cgroupv1 code, so there is no need
for it to implement cgroupv2 stuff.
Make it v1-specific, and panic if it is called from v2 code (since this
is an internal function, the panic would mean incorrect runc code).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
It's bad and wrong to use these functions for any cgroupv2 code,
and there are no existing users (in runc, at least).
Make them return an error in such case.
Also, remove the cgroupv2-specific handling from
findCgroupMountpointAndRootFromReader().
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This function should not really be used for cgroupv2 code.
Currently it is used in kubernetes code, so we can't remove
the v2 case yet.
Add a TODO item to remove v2 code once kubernetes is converted
to not use it, and separate out v1 code.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This function is not used and were never used in any cgroupv2 code.
To have it stay that way, let it return error in case it's called
for v2.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This (and the converting function) is only used by one of the four
cgroup drivers. The other three do some checking and conversion in
place, so let the fs2 do the same.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
... and mem+swap is not explicitly set otherwise.
This ensures compatibility with cgroupv1 controller which interprets
things this way.
With this fixed, we can finally enable swap tests for cgroupv2.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The function GetClosestMountpointAncestor is not very efficient,
does not really belong to cgroup package, and is only used once
(from fs/cpuset.go).
Remove it, replacing with the implementation based on moby/sys/mountinfo
parser.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This function is not very efficient, does not really belong to cgroup
package, and is only used once (from fs/cpuset.go).
Prepare to remove it by replacing with the implementation based on
the parser from github.com/moby/sys/mountinfo parser.
This commit is here to make sure the proposed replacement passes the
unit test.
Funny, but the unit test need to be slightly modified since it
supplies the wrong mountinfo (space as the first character, empty line
at the end).
Validated by
$ go test -v -run Ance
=== RUN TestGetClosestMountpointAncestor
--- PASS: TestGetClosestMountpointAncestor (0.00s)
PASS
ok github.com/opencontainers/runc/libcontainer/cgroups 0.002s
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
In cgroup v2, when memory and memorySwap set to the same value which is greater than zero,
runc should write zero in `memory.swap.max` to disable swap.
Signed-off-by: lifubang <lifubang@acmcoder.com>
The resources.MemorySwap field from OCI is memory+swap, while cgroupv2
has a separate swap limit, so subtract memory from the limit (and make
sure values are set and sane).
Make sure to set MemorySwapMax for systemd, too. Since systemd does not
have MemorySwapMax for cgroupv1, it is only needed for v2 driver.
[v2: return -1 on any negative value, add unit test]
[v3: treat any negative value other than -1 as error]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Make use of errors.Is() and errors.As() where appropriate to check
the underlying error. The biggest motivation is to simplify the code.
The feature requires go 1.13 but since merging #2256 we are already
not supporting go 1.12 (which is an unsupported release anyway).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Using errors.Unwrap() is not the best thing to do, since it returns
nil in case of an error which was not wrapped. More to say,
errors package provides more elegant ways to check for underlying
errors, such as errors.As() and errors.Is().
This reverts commit f8e138855d, reversing
changes made to 6ca9d8e6da.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Kir Kolyshkin