validation: add different test cases for blkio cgroup tests

Test if blkio cgroups tests work corectly, with different rate values.
Also test it with empty weight values in the input json file.

Signed-off-by: Dongsu Park <[email protected]>

Author: Dongsu Park

validation/linux_cgroups_blkio.go

@@ -1,36 +1,72 @@
 package main
 
 import (
+	"fmt"
+	"runtime"
+
 	"github.com/mndrix/tap-go"
 	"github.com/opencontainers/runtime-tools/cgroups"
 	"github.com/opencontainers/runtime-tools/validation/util"
 )
 
-func main() {
+func testBlkioCgroups(rate uint64, isEmpty bool) error {
 	var weight uint16 = 500
 	var leafWeight uint16 = 300
-	var major, minor int64 = 8, 0
-	var rate uint64 = 102400
+
+	// It's assumed that a device /dev/sda (8:0) exists on the test system.
+	// The minor number must be always 0, as it's only allowed to set blkio
+	// weights to a whole block device /dev/sda, not to partitions like sda1.
+	var major int64 = 8
+	var minor int64
 
 	t := tap.New()
 	t.Header(0)
 	defer t.AutoPlan()
 
 	g, err := util.GetDefaultGenerator()
 	if err != nil {
-		util.Fatal(err)
+		return err
 	}
+
 	g.SetLinuxCgroupsPath(cgroups.AbsCgroupPath)
-	g.SetLinuxResourcesBlockIOWeight(weight)
-	g.SetLinuxResourcesBlockIOLeafWeight(leafWeight)
+
+	if !isEmpty {
+		g.SetLinuxResourcesBlockIOWeight(weight)
+		g.SetLinuxResourcesBlockIOLeafWeight(leafWeight)
+	}
+
 	g.AddLinuxResourcesBlockIOWeightDevice(major, minor, weight)
 	g.AddLinuxResourcesBlockIOLeafWeightDevice(major, minor, leafWeight)
 	g.AddLinuxResourcesBlockIOThrottleReadBpsDevice(major, minor, rate)
 	g.AddLinuxResourcesBlockIOThrottleWriteBpsDevice(major, minor, rate)
 	g.AddLinuxResourcesBlockIOThrottleReadIOPSDevice(major, minor, rate)
 	g.AddLinuxResourcesBlockIOThrottleWriteIOPSDevice(major, minor, rate)
+
 	err = util.RuntimeOutsideValidate(g, t, util.ValidateLinuxResourcesBlockIO)
 	if err != nil {
-		util.Fatal(err)
+		return err
+	}
+	return nil
+}
+
+func main() {
+	if "linux" != runtime.GOOS {
+		util.Fatal(fmt.Errorf("linux-specific cgroup test"))
+	}
+
+	cases := []struct {
+		rate    uint64
+		isEmpty bool
+	}{
+		{102400, false},
+		{204800, false},
+		{102400, true},
+		{204800, true},
+	}
+
+	for _, c := range cases {
+		if err := testBlkioCgroups(c.rate, c.isEmpty); err != nil {
+			util.Fatal(err)
+		}
 	}
 }