node: e2e: run deleteSync in parallel

speedup the cleanup after testcases deleting pods in separate
goroutines.
The post-test cleanup stage must be done carefully since pod require
exclusive allocation - so pods must take all the steps to properly
cleanup the tests to avoid to pollute the environment, but
this has a negative effect on test duration (take longer).

Hence, we add safe speedups like doing pod deletions in parallel.

Signed-off-by: Francesco Romani <fromani@redhat.com>

test/e2e_node/podresources_test.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"strings"
+	"sync"
 	"time"
 
 	v1 "k8s.io/api/core/v1"
@@ -140,12 +141,24 @@ func (tpd *testPodData) createPodsForTest(f *framework.Framework, podReqs []podD
 	}
 }
 
+/* deletePodsForTest clean up all the pods run for a testcase. Must ensure proper cleanup */
 func (tpd *testPodData) deletePodsForTest(f *framework.Framework) {
+	podNS := f.Namespace.Name
+	var wg sync.WaitGroup
 	for podName := range tpd.PodMap {
+		wg.Add(1)
+		go func(podName string) {
+			defer ginkgo.GinkgoRecover()
+			defer wg.Done()
+
 			deletePodSyncByName(f, podName)
+			waitForAllContainerRemoval(podName, podNS)
+		}(podName)
 	}
+	wg.Wait()
 }
 
+/* deletePod removes pod during a test. Should do a best-effort clean up */
 func (tpd *testPodData) deletePod(f *framework.Framework, podName string) {
 	_, ok := tpd.PodMap[podName]
 	if !ok {