Ignore cpu realtime options on cgroups V2 systems

`--cpu-rt-period` and `--cpu-rt-runtime` options are only
supported on cgroups V2 systems.

Therefore, podman prints an warning message and ignores these
options when we use cgroups V2 systems.

Related to: containers#15666

Signed-off-by: Toshiki Sonoda <sonoda.toshiki@fujitsu.com>

pkg/specgen/generate/validate.go

@@ -82,7 +82,7 @@ func verifyContainerResourcesCgroupV1(s *specgen.SpecGenerator) ([]string, error
 		}
 	}
 
-	// CPU Checks
+	// CPU checks
 	if s.ResourceLimits.CPU != nil {
 		cpu := s.ResourceLimits.CPU
 		if cpu.Shares != nil && !sysInfo.CPUShares {
@@ -169,6 +169,7 @@ func verifyContainerResourcesCgroupV2(s *specgen.SpecGenerator) ([]string, error
 		return warnings, nil
 	}
 
+	// Memory checks
 	if s.ResourceLimits.Memory != nil && s.ResourceLimits.Memory.Swap != nil {
 		own, err := utils.GetOwnCgroup()
 		if err != nil {
@@ -198,6 +199,19 @@ func verifyContainerResourcesCgroupV2(s *specgen.SpecGenerator) ([]string, error
 			s.ResourceLimits.Memory.Swap = nil
 		}
 	}
+
+	// CPU checks
+	if s.ResourceLimits.CPU != nil {
+		cpu := s.ResourceLimits.CPU
+		if cpu.RealtimePeriod != nil {
+			warnings = append(warnings, "Realtime period not supported on cgroups V2 systems")
+			cpu.RealtimePeriod = nil
+		}
+		if cpu.RealtimeRuntime != nil {
+			warnings = append(warnings, "Realtime runtime not supported on cgroups V2 systems")
+			cpu.RealtimeRuntime = nil
+		}
+	}
 	return warnings, nil
 }
 

test/e2e/run_cpu_test.go

@@ -138,4 +138,20 @@ var _ = Describe("Podman run cpu", func() {
 		result.WaitWithDefaultTimeout()
 		Expect(result).To(ExitWithError())
 	})
+
+	It("podman run invalid cpu-rt-period with cgroupsv2", func() {
+		SkipIfCgroupV1("testing options that only work in cgroup v2")
+		result := podmanTest.Podman([]string{"run", "--rm", "--cpu-rt-period=5000", ALPINE, "ls"})
+		result.WaitWithDefaultTimeout()
+		Expect(result).Should(Exit(0))
+		Expect(result.ErrorToString()).To(ContainSubstring("Realtime period not supported on cgroups V2 systems"))
+	})
+
+	It("podman run invalid cpu-rt-runtime with cgroupsv2", func() {
+		SkipIfCgroupV1("testing options that only work in cgroup v2")
+		result := podmanTest.Podman([]string{"run", "--rm", "--cpu-rt-runtime=5000", ALPINE, "ls"})
+		result.WaitWithDefaultTimeout()
+		Expect(result).Should(Exit(0))
+		Expect(result.ErrorToString()).To(ContainSubstring("Realtime runtime not supported on cgroups V2 systems"))
+	})
 })