Merge pull request #18697 from jfrazelle/pids-cgroup

Add PIDs cgroup support to Docker
Upstream-commit: dd32445ecc6b706e8681dcc9d80c42c9b6cbf6cd
Component: engine

components/engine/integration-cli/docker_cli_run_unix_test.go

@@ -968,3 +968,15 @@ func (s *DockerSuite) TestRunDeviceSymlink(c *check.C) {
 	c.Assert(err, check.NotNil)
 	c.Assert(strings.Trim(out, "\r\n"), checker.Contains, "not a device node", check.Commentf("expected output 'not a device node'"))
 }
+
+// TestRunPidsLimit makes sure the pids cgroup is set with --pids-limit
+func (s *DockerSuite) TestRunPidsLimit(c *check.C) {
+	testRequires(c, pidsLimit)
+
+	file := "/sys/fs/cgroup/pids/pids.max"
+	out, _ := dockerCmd(c, "run", "--name", "skittles", "--pids-limit", "2", "busybox", "cat", file)
+	c.Assert(strings.TrimSpace(out), checker.Equals, "2")
+
+	out = inspectField(c, "skittles", "HostConfig.PidsLimit")
+	c.Assert(out, checker.Equals, "2", check.Commentf("setting the pids limit failed"))
+}

components/engine/integration-cli/requirements_unix.go

@@ -33,6 +33,12 @@ var (
 		},
 		"Test requires Oom control enabled.",
 	}
+	pidsLimit = testRequirement{
+		func() bool {
+			return SysInfo.PidsLimit
+		},
+		"Test requires pids limit enabled.",
+	}
 	kernelMemorySupport = testRequirement{
 		func() bool {
 			return SysInfo.KernelMemory