e2e: topomgr: early check to detect VFs, not PFs

The e2e_node topology_manager check have a early, quick check
to rule out systems without sriov device, thus skipping the tests.

The first version of the ckeck detected PFs, (Physical Functions),
under the assumption that VFs (Virtual Functions) were already been
created. This works because, obviously, you can't have VFs without PFs.

However, it's a little safer and easier to understand if we check
firectly for VFs, bailing out from systems which don't provide them.

Nothing changes for properly configured test systems.

Signed-off-by: Francesco Romani <[email protected]>

Author: ffromani

test/e2e_node/topology_manager_test.go

@@ -83,7 +83,7 @@ func detectCoresPerSocket() int {
 }
 
 func detectSRIOVDevices() int {
-	outData, err := exec.Command("/bin/sh", "-c", "ls /sys/bus/pci/devices/*/sriov_totalvfs | wc -w").Output()
+	outData, err := exec.Command("/bin/sh", "-c", "ls /sys/bus/pci/devices/*/physfn | wc -w").Output()
 	framework.ExpectNoError(err)
 
 	devCount, err := strconv.Atoi(strings.TrimSpace(string(outData)))
@@ -728,7 +728,7 @@ func runTopologyManagerTests(f *framework.Framework) {
 			e2eskipper.Skipf("this test is meant to run on a system with at least 4 cores per socket")
 		}
 		if sriovdevCount == 0 {
-			e2eskipper.Skipf("this test is meant to run on a system with at least one SRIOV device")
+			e2eskipper.Skipf("this test is meant to run on a system with at least one configured VF from SRIOV device")
 		}
 
 		configMap := getSRIOVDevicePluginConfigMap(framework.TestContext.SriovdpConfigMapFile)