blob: 1e15ae2c3b55028865132b2c77f66ec7d519e52e [file] [log] [blame]
// +build linux
package libcontainer
import (
"encoding/binary"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"testing"
"time"
"golang.org/x/sys/unix"
)
type notifyFunc func(paths map[string]string) (<-chan struct{}, error)
func testMemoryNotification(t *testing.T, evName string, notify notifyFunc, targ string) {
memoryPath, err := ioutil.TempDir("", "testmemnotification-"+evName)
if err != nil {
t.Fatal(err)
}
evFile := filepath.Join(memoryPath, evName)
eventPath := filepath.Join(memoryPath, "cgroup.event_control")
if err := ioutil.WriteFile(evFile, []byte{}, 0700); err != nil {
t.Fatal(err)
}
if err := ioutil.WriteFile(eventPath, []byte{}, 0700); err != nil {
t.Fatal(err)
}
paths := map[string]string{
"memory": memoryPath,
}
ch, err := notify(paths)
if err != nil {
t.Fatal("expected no error, got:", err)
}
data, err := ioutil.ReadFile(eventPath)
if err != nil {
t.Fatal("couldn't read event control file:", err)
}
var eventFd, evFd int
var arg string
if targ != "" {
_, err = fmt.Sscanf(string(data), "%d %d %s", &eventFd, &evFd, &arg)
} else {
_, err = fmt.Sscanf(string(data), "%d %d", &eventFd, &evFd)
}
if err != nil || arg != targ {
t.Fatalf("invalid control data %q: %s", data, err)
}
// dup the eventfd
efd, err := unix.Dup(eventFd)
if err != nil {
t.Fatal("unable to dup eventfd:", err)
}
defer unix.Close(efd)
buf := make([]byte, 8)
binary.LittleEndian.PutUint64(buf, 1)
if _, err := unix.Write(efd, buf); err != nil {
t.Fatal("unable to write to eventfd:", err)
}
select {
case <-ch:
case <-time.After(100 * time.Millisecond):
t.Fatal("no notification on channel after 100ms")
}
// simulate what happens when a cgroup is destroyed by cleaning up and then
// writing to the eventfd.
if err := os.RemoveAll(memoryPath); err != nil {
t.Fatal(err)
}
if _, err := unix.Write(efd, buf); err != nil {
t.Fatal("unable to write to eventfd:", err)
}
// give things a moment to shut down
select {
case _, ok := <-ch:
if ok {
t.Fatal("expected no notification to be triggered")
}
case <-time.After(100 * time.Millisecond):
t.Fatal("channel not closed after 100ms")
}
if _, _, err := unix.Syscall(unix.SYS_FCNTL, uintptr(evFd), unix.F_GETFD, 0); err != unix.EBADF {
t.Errorf("expected event control to be closed, but received error %s", err.Error())
}
if _, _, err := unix.Syscall(unix.SYS_FCNTL, uintptr(eventFd), unix.F_GETFD, 0); err != unix.EBADF {
t.Errorf("expected event fd to be closed, but received error %s", err.Error())
}
}
func TestNotifyOnOOM(t *testing.T) {
f := func(paths map[string]string) (<-chan struct{}, error) {
return notifyOnOOM(paths)
}
testMemoryNotification(t, "memory.oom_control", f, "")
}
func TestNotifyMemoryPressure(t *testing.T) {
tests := map[PressureLevel]string{
LowPressure: "low",
MediumPressure: "medium",
CriticalPressure: "critical",
}
for level, arg := range tests {
f := func(paths map[string]string) (<-chan struct{}, error) {
return notifyMemoryPressure(paths, level)
}
testMemoryNotification(t, "memory.pressure_level", f, arg)
}
}