Commit Graph

684 Commits

Author SHA1 Message Date
Sebastiaan van Stijn 7fcfb3fad6 Merge pull request #3030 from kolyshkin/openat2-improve
libct/cg/OpenFile: fix/improve openat2 handling
2021-09-03 16:54:39 +02:00
Kir Kolyshkin d8da00355e *: add go-1.17+ go:build tags
Go 1.17 introduce this new (and better) way to specify build tags.
For more info, see https://golang.org/design/draft-gobuild.

As a way to seamlessly switch from old to new build tags, gofmt (and
gopls) from go 1.17 adds the new tags along with the old ones.

Later, when go < 1.17 is no longer supported, the old build tags
can be removed.

Now, as I started to use latest gopls (v0.7.1), it adds these tags
while I edit. Rather than to randomly add new build tags, I guess
it is better to do it once for all files.

Mind that previous commits removed some tags that were useless,
so this one only touches packages that can at least be built
on non-linux.

Brought to you by

        go1.17 fmt ./...

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-30 20:58:22 -07:00
Kir Kolyshkin 1b17ec95af libct/cg: rm "unsupported.go" files
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>
2021-08-30 20:56:35 -07:00
Kir Kolyshkin dbb9fc03ae libct/*: remove linux build tag from some pkgs
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>
2021-08-30 20:52:07 -07:00
Kir Kolyshkin 3c7db3827c Merge pull request #2883 from flouthoc/master
Add support for rdma cgroup introduced in Linux Kernel 4.11
2021-08-30 20:02:04 -07:00
Kir Kolyshkin 1b2adcfe56 libct/cg/v1: workaround CPU quota period set failure
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>
2021-08-26 13:11:22 -07:00
Sebastiaan van Stijn 8b59b768a9 Merge pull request #3182 from cyphar/revert-3159
Revert "libct/devices: change devices.Type to be a string"
2021-08-25 10:55:04 +02:00
Qiang Huang b4b797200e Merge pull request #3136 from kolyshkin/cg-d-c
libct/cg: rm dead code to improve clarity
2021-08-25 14:46:27 +08:00
Aleksa Sarai 09b80811f6 Revert "libct/devices: change devices.Type to be a string"
This reverts commit 814f3ae1d9. This
changed the on-disk state which breaks runc when it has to operate on
containers started with an older runc version. Working around this is
far more complicated than just reverting it.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
2021-08-25 14:11:32 +10:00
Kir Kolyshkin bbcf96f91f libct/cg/devices: stop using regex
Looking into data generated by setting

	GODEBUG="inittrace=1"

I have noticed this line:

init github.com/opencontainers/runc/libcontainer/cgroups/devices @1.2 ms, 0.020 ms clock, 10512 bytes, 133 allocs

This is the leader for both bytes and allocs among the packages from
this repo, and all of it is caused by a single regex:

> var devicesListRegexp = regexp.MustCompile(`^([abc])\s+(\d+|\*):(\d+|\*)\s+([rwm]+)$`)

It seems that the same parsing can be done without relying on
a regular expression, no decrease in readability, and 2x faster
(according to the benchmark added), and also makes runc start
slightly faster and leaner.

Before:
    BenchmarkParseLine-4   	  176240	      6768 ns/op	    6576 B/op	      64 allocs/op

After:
    BenchmarkParseLine-4   	  322441	      3535 ns/op	    5520 B/op	      53 allocs/op

[v2: single split with SplitFunc; fix a typo in error message]
[v3: rebase after 3159 merge; re-ran benchmarks (results are similar)]

Co-authored-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-23 17:04:09 -07:00
Kir Kolyshkin 34df203d13 Merge pull request #3159 from thaJeztah/norunes
libct/devices: change devices.Type to be a string
2021-08-23 16:58:34 -07:00
flouthoc b3d14488b5 Add support for rdma cgroup introduced in Linux Kernel 4.11
Signed-off-by: Aditya Rajan <flouthoc.git@gmail.com>
2021-08-23 12:25:33 +05:30
Kir Kolyshkin 9a095e44db libct/cg/sd/v1: add SkipFreezeOnSet knob
This is helpful to kubernetes in cases it knows for sure that the freeze
is not required (since it created the systemd unit with no device
restrictions).

As the code is trivial, no tests are required.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-18 12:43:55 -07:00
Kir Kolyshkin fec49f2a6c libct/cg/sd/v1: add freezeBeforeSet unit test
Add a test for freezeBeforeSet, checking various scenarios including
those that were failing before the fix in the previous commit.

[v2: add more cases, add a check before creating a unit.]

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-18 12:43:55 -07:00
Odin Ugedal 41043673b7 libct/cg/sd/v1: Fix unnecessary freeze/thaw
This fixes the behavior intended to avoid freezing containers/control
groups without it being necessary. This is important for end users of
libcontainer who rely on the behavior of no freeze.

The previous implementation would always get error trying to get
DevicePolicy from the Unit via dbus, since the Unit interface doesn't
contain DevicePolicy.

Signed-off-by: Odin Ugedal <odin@uged.al>
2021-08-18 12:43:36 -07:00
Kir Kolyshkin 75761bccf7 Fix codespell warnings, add codespell to ci
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>
2021-08-17 16:12:35 -07:00
Sebastiaan van Stijn 814f3ae1d9 libct/devices: change devices.Type to be a string
Possibly there was a specific reason to use a rune for this, but I noticed
that there's various parts in the code that has to convert values from a
string to this type. Using a string as type for this can simplify some of
that code.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2021-08-13 00:55:22 +02:00
Kir Kolyshkin bd50e7c420 libct/cg/OpenFile: check cgroupFd on error
opencontainers/runc issue 3026 describes a scenario in which OpenFile
failed to open a legitimate existing cgroupfs file. Added debug
(similar to what this commit does) shown that cgroupFd is no longer
opened to "/sys/fs/cgroup", but to "/" (it's not clear what caused it,
and the source code is not available, but they might be using the same
process on the both sides of the container/chroot/pivot_root/mntns
boundary, or remounting /sys/fs/cgroup).

Consider such use incorrect, but give a helpful hint as two what is
going on by wrapping the error in a more useful message.

NB: this can potentially be fixed by reopening the cgroupFd once we
detected that it's screwed, and retrying openat2. Alas I do not have
a test case for this, so left this as a TODO suggestion.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-11 17:00:05 -07:00
Kir Kolyshkin c2d9668cc5 libct/cg/OpenFile: fix openat2 vs top cgroup dir
Fix reading cgroup files from the top cgroup directory, i.e.
/sys/fs/cgroup.

The code was working for for any subdirectory of /sys/fs/cgroup, but
for dir="/sys/fs/cgroup" a fallback (open and fstatfs) was used, because
of the way the function worked with the dir argument.

Fix those cases, and add unit tests to make sure they work. While at it,
make the rules for dir and name components more relaxed, and add test
cases for this, too.

While at it, improve OpenFile documentation, and remove a duplicated
doc comment for openFile.

Without these fixes, the unit test fails the following cases:

    file_test.go:67: case {path:/sys/fs/cgroup name:cgroup.controllers}: fallback
    file_test.go:67: case {path:/sys/fs/cgroup/ name:cgroup.controllers}: openat2 /sys/fs/cgroup//cgroup.controllers: invalid cross-device link
    file_test.go:67: case {path:/sys/fs/cgroup/ name:/cgroup.controllers}: openat2 /sys/fs/cgroup///cgroup.controllers: invalid cross-device link
    file_test.go:67: case {path:/ name:/sys/fs/cgroup/cgroup.controllers}: fallback
    file_test.go:67: case {path:/ name:sys/fs/cgroup/cgroup.controllers}: fallback
    file_test.go:67: case {path:/sys/fs/cgroup/cgroup.controllers name:}: openat2 /sys/fs/cgroup/cgroup.controllers/: not a directory

Here "fallback" means openat2-based implementation fails, and the fallback code
is used (and works).

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-09 11:17:05 -07:00
Kir Kolyshkin 1cbfe23464 libct/cg: rm dead code
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>
2021-08-08 13:03:51 -07:00
Kir Kolyshkin d0c3bc44e7 libct/cg: GetAllPids: optimize for go 1.16+
filepath.WalkDir function, introduced in Go 1.16, doesn't do stat(2)
on every entry, and is therefore somewhat faster (see below).

Since we have to support Go 1.15, keep the old version for backward
compatibility.

Add a quick benchmark, which shows approximately 3x improvement:

        $ go1.15.15 test -bench AllPid -run xxx .
	BenchmarkGetAllPids-4   	      48	  23528839 ns/op

        $ go version
        go version go1.16.6 linux/amd64
        $ go test -bench AllPid -run xxx .
	BenchmarkGetAllPids-4   	     147	   7700170 ns/op

(Unrelated but worth noting -- go 1.17rc2 is pushing it even further)

        $ go1.17rc2 test -bench AllPid -run xxx .
	BenchmarkGetAllPids-4   	     164	   6820994 ns/op

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-05 16:22:18 -07:00
Kir Kolyshkin 363468d0e4 libct/cg: improve GetAllPids and readProcsFile
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>
2021-08-05 16:22:11 -07:00
Kir Kolyshkin 504271a374 libct/cg: move GetAllPids out of utils.go
This is just moving the code around to ease the code review, no other
changes.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-08-05 16:00:03 -07:00
Kir Kolyshkin a91ce3062f libct/*_test.go: use t.TempDir
Replace ioutil.TempDir (mostly) with t.TempDir, which require no
explicit cleanup.

While at it, fix incorrect usage of os.ModePerm in libcontainer/intelrdt
test. This is supposed to be a mask, not mode bits.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-27 01:41:47 -07:00
Kir Kolyshkin f6a56f603c libct/cg/fs/*_test.go: use t.TempDir
This simplifies the code as no explicit cleanup is required.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-27 01:41:47 -07:00
Kir Kolyshkin 2d1645d2e5 libct/cg/fscommon: drop go 1.13 compatibility
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-27 01:41:47 -07:00
Kir Kolyshkin a71102624d libct/cg/sd: add TestPodSkipDevicesUpdate
TestPodSkipDevicesUpdate checks that updating a pod having SkipDevices: true
does not result in spurious "permission denied" errors in a container
running under the pod. The test is somewhat similar in nature to the
@test "update devices [minimal transition rules]" in tests/integration,
but uses a pod.

This tests the validity of freezeBeforeSet in v1.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-15 00:07:22 -07:00
Kir Kolyshkin 52dd96db6b libct/cg/sd: TestFreezePodCgroup: rm explicit freeze
This was initially added by commit 3e5c199708 because Set (with
r.Freezer = Frozen) was not able to freeze a container.

Now (see a few previous commits) Set can do the freeze, so the explicit
Freeze is no longer needed.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-15 00:07:19 -07:00
Kir Kolyshkin f2db87986c libct/cg/sd/v1: Set: avoid unnecessary freeze/thaw
Introduce freezeBeforeSet, which contains the logic of figuring out
whether we need to freeze/thaw around setting systemd unit properties.

In particular, if SkipDevices is set, and the current unit properties
allow all devices, there is no need to freeze and thaw, as systemd
won't write any device rules in this case.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-15 00:07:10 -07:00
Kir Kolyshkin 67cfd3d400 libct/cg/sd/v1: Set: don't overwrite r.Freezer
m.Freeze method changes m.cgroups.Resources.Freezer field, which should
not be done while we're temporarily freezing the cgroup in Set. If this
field is changed, and r == m.cgroups.Resources (as it often happens),
this results in inability to freeze the container using Set().

To fix, add and use a method which does not change r.Freezer field.

A test case for the bug will be added separately.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-14 23:42:35 -07:00
Aleksa Sarai 57e3c54182 cgroupv2: ebpf: ignore inaccessible existing programs
This is necessary in order for runc to be able to configure device
cgroups with --systemd-cgroup on distributions that have very strict
SELinux policies such as openSUSE MicroOS[1].

The core issue here is that systemd is adding its own BPF policy that
has an SELinux label such that runc cannot interact with it. In order to
work around this, we can just ignore the policy -- in theory this
behaviour is not correct but given that the most obvious case
(--systemd-cgroup) will still handle updates correctly, this logic is
reasonable.

[1]: https://bugzilla.suse.com/show_bug.cgi?id=1182428

Fixes: d0f2c25f52 ("cgroup2: devices: replace all existing filters when attaching")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
2021-07-14 11:17:19 +10:00
Aleksa Sarai 2c01cec8ac merge branch 'pr-3067'
Odin Ugedal (2):
  libct/cg/sd: Don't freeze cgroup on cgroup v2 Set
  Update device update tests

LGTMs: kolyshkin mrunalp cyphar
Closes #3067
2021-07-13 12:59:29 +10:00
Mrunal Patel dc3236f957 Merge pull request #3070 from kolyshkin/unconvert
ci: enable unconvert linter, fix its warnings
2021-07-12 16:47:14 -04:00
Odin Ugedal 3e5c199708 libct/cg/sd: Add freezer tests
This test the issues fixed by the two preceding commits.

Co-Authored-By: Kir Kolyshkin <kolyshkin@gmail.com>
Signed-off-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-08 19:32:39 -07:00
Odin Ugedal 294c4866ea libct/cg/fs/freezer.GetState: report current cgroup state
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>
2021-07-08 19:32:08 -07:00
Odin Ugedal f33be7cc98 libct/cg/sd: Don't freeze cgroup on cgroup v2 Set
Since device updates in cgroup v2 are atomic for systemd, there is no
need to freeze the processes before running the updates.

Signed-off-by: Odin Ugedal <odin@uged.al>
2021-07-07 22:44:08 +02:00
Kir Kolyshkin be1d5f83c0 ci: enable unconvert linter, fix its warnings
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-07-07 10:42:48 -07:00
Kir Kolyshkin a7cfb23b88 *: stop using pkg/errors
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin b60e2edf75 libct/cg: stop using pkg/errors
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin a6cc36a836 libct/cg/ebpf: stop using pkg/errors
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin f137aaa2c8 libct/cg/devices: stop using pkg/errors
Use Go native errors wrapping.

Introduce wrapErr helper to minimise the patch size.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin 56e478046a *: ignore errorlint warnings about unix.* errors
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>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin f6a0899b7f *: use errors.As and errors.Is
Do this for all errors except one from unix.*.

This fixes a bunch of errorlint warnings, like these

libcontainer/generic_error.go:25:15: type assertion on error will fail on wrapped errors. Use errors.As to check for specific errors (errorlint)
	if le, ok := err.(Error); ok {
	             ^
libcontainer/factory_linux_test.go:145:14: type assertion on error will fail on wrapped errors. Use errors.As to check for specific errors (errorlint)
	lerr, ok := err.(Error)
	            ^
libcontainer/state_linux_test.go:28:11: type assertion on error will fail on wrapped errors. Use errors.As to check for specific errors (errorlint)
	_, ok := err.(*stateTransitionError)
	         ^
libcontainer/seccomp/patchbpf/enosys_linux.go:88:4: 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>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin adbac31d88 libct: fix errorlint warning about strconv.NumError
This one is tough as errorlint insists on using errors.Is, and the
latter is known to not work for Go 1.13 which we still support.

So, add a nolint annotation to suppress the warning, and a TODO to
address it later.

For intelrdt, we can do the same, but it is easier to reuse the very
same function from fscommon (note we can't use fscommon for other stuff
as it expects cgroupfs).

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin 7be93a66b9 *: fmt.Errorf: use %w when appropriate
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>
2021-06-22 16:09:47 -07:00
Kir Kolyshkin 825335b2b7 libct/cg/fs2: fix/unify parsing errors
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().

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 missing scanner.Err() checks.

[v2: use parseError, not ParseError]

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 12:00:54 -07:00
Kir Kolyshkin 5a186d390f libct/cg/fs: fix/unify parsing errors
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>
2021-06-22 11:59:54 -07:00
Kir Kolyshkin f813174d5e libct/cg/fscommon: introduce and use ParseError
1. Introduce ParseError type as a way to unify error messages related to
   file parsing. Use it from GetCgroup* functions.

2. Do not discard the error from strconv.Parse{Int,Uint} -- it contains
   the value being parsed, and the details about the error.

2. As the error above already contains the value, drop it from format.

[v2: use path.Join in Error]

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 11:52:26 -07:00
Kir Kolyshkin adcd3b4451 libct/cg/fs[2]: simplify getting pid stats
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>
2021-06-22 11:44:31 -07:00
Kir Kolyshkin 4e33094277 libct/cg/fs/stats_util_test: fix errors
1. No \n needed in t.Errorf/t.Fatalf.

2. Some cosmetic changes.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
2021-06-22 11:44:12 -07:00