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Revert "Merge pull request 101888 from kolyshkin/update-runc-rc94"

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This reverts commit b1b06fe0a4, reversing
changes made to 382a33986b.
This commit is contained in:
Jordan Liggitt
2021-05-18 09:12:04 -04:00
parent 7ccd90e7d7
commit 4b45d0d921
336 changed files with 5393 additions and 17166 deletions
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58
vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs/freezer.go generated vendored
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@@ -12,7 +12,6 @@ import (
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
"github.com/opencontainers/runc/libcontainer/configs"
"github.com/sirupsen/logrus"
"golang.org/x/sys/unix"
)
@@ -27,62 +26,29 @@ func (s *FreezerGroup) Apply(path string, d *cgroupData) error {
return join(path, d.pid)
}
func (s *FreezerGroup) Set(path string, r *configs.Resources) (Err error) {
switch r.Freezer {
func (s *FreezerGroup) Set(path string, cgroup *configs.Cgroup) error {
switch cgroup.Resources.Freezer {
case configs.Frozen:
defer func() {
if Err != nil {
// Freezing failed, and it is bad and dangerous
// to leave the cgroup in FROZEN or FREEZING
// state, so (try to) thaw it back.
_ = fscommon.WriteFile(path, "freezer.state", string(configs.Thawed))
}
}()
// As per older kernel docs (freezer-subsystem.txt before
// kernel commit ef9fe980c6fcc1821), if FREEZING is seen,
// userspace should either retry or thaw. While current
// kernel cgroup v1 docs no longer mention a need to retry,
// even a recent kernel (v5.4, Ubuntu 20.04) can't reliably
// freeze a cgroup v1 while new processes keep appearing in it
// the kernel (tested on v5.4, Ubuntu 20.04) can't reliably
// freeze a cgroup while new processes keep appearing in it
// (either via fork/clone or by writing new PIDs to
// cgroup.procs).
//
// The numbers below are empirically chosen to have a decent
// chance to succeed in various scenarios ("runc pause/unpause
// with parallel runc exec" and "bare freeze/unfreeze on a very
// slow system"), tested on RHEL7 and Ubuntu 20.04 kernels.
// The number of retries below is chosen to have a decent
// chance to succeed even in the worst case scenario (runc
// pause/unpause with parallel runc exec).
//
// Adding any amount of sleep in between retries did not
// increase the chances of successful freeze in "pause/unpause
// with parallel exec" reproducer. OTOH, adding an occasional
// sleep helped for the case where the system is extremely slow
// (CentOS 7 VM on GHA CI).
//
// Alas, this is still a game of chances, since the real fix
// belong to the kernel (cgroup v2 do not have this bug).
// increase the chances of successful freeze.
for i := 0; i < 1000; i++ {
if i%50 == 49 {
// Occasional thaw and sleep improves
// the chances to succeed in freezing
// in case new processes keep appearing
// in the cgroup.
_ = fscommon.WriteFile(path, "freezer.state", string(configs.Thawed))
time.Sleep(10 * time.Millisecond)
}
if err := fscommon.WriteFile(path, "freezer.state", string(configs.Frozen)); err != nil {
return err
}
if i%25 == 24 {
// Occasional short sleep before reading
// the state back also improves the chances to
// succeed in freezing in case of a very slow
// system.
time.Sleep(10 * time.Microsecond)
}
state, err := fscommon.ReadFile(path, "freezer.state")
if err != nil {
return err
@@ -92,9 +58,6 @@ func (s *FreezerGroup) Set(path string, r *configs.Resources) (Err error) {
case "FREEZING":
continue
case string(configs.Frozen):
if i > 1 {
logrus.Debugf("frozen after %d retries", i)
}
return nil
default:
// should never happen
@@ -102,13 +65,16 @@ func (s *FreezerGroup) Set(path string, r *configs.Resources) (Err error) {
}
}
// Despite our best efforts, it got stuck in FREEZING.
// Leaving it in this state is bad and dangerous, so
// let's (try to) thaw it back and error out.
_ = fscommon.WriteFile(path, "freezer.state", string(configs.Thawed))
return errors.New("unable to freeze")
case configs.Thawed:
return fscommon.WriteFile(path, "freezer.state", string(configs.Thawed))
case configs.Undefined:
return nil
default:
return fmt.Errorf("Invalid argument '%s' to freezer.state", string(r.Freezer))
return fmt.Errorf("Invalid argument '%s' to freezer.state", string(cgroup.Resources.Freezer))
}
}