e2e:rps: print device path with wrong mask

In case the test failed, we asserts only the desired and actual mask,
but we are not specifing the device on which the RPS mask was bad.

This patch adds the full device path as part of the error message.

Signed-off-by: Talor Itzhak <titzhak@redhat.com>

test/e2e/performanceprofile/functests/1_performance/performance.go

@@ -375,15 +375,17 @@ var _ = Describe("[rfe_id:27368][performance]", Ordered, func() {
 					"-prune", "-o",
 					"-type", "f",
 					"-name", "rps_cpus",
+					"-printf", "%p ",
 					"-exec", "cat", "{}", ";",
 				}
-				devsRPS, err := nodes.ExecCommandOnNode(cmd, &node)
+				devsRPSContent, err := nodes.ExecCommandOnNode(cmd, &node)
 				Expect(err).ToNot(HaveOccurred(), "failed to exec command %q on node %q", cmd, node.Name)
-				for _, devRPS := range strings.Split(devsRPS, "\n") {
-					rpsCPUs, err = components.CPUMaskToCPUSet(devRPS)
+				devsRPSMap := makeDevRPSMap(devsRPSContent)
+				for path, mask := range devsRPSMap {
+					rpsCPUs, err = components.CPUMaskToCPUSet(mask)
 					Expect(err).ToNot(HaveOccurred())
 					Expect(rpsCPUs.Equals(expectedRPSCPUs)).To(BeTrue(),
-						"a host device rps mask is different from the reserved CPUs; have %q want %q", devRPS, expectedRPSCPUsMask)
+						"a host virtual device: %q rps mask is different from the reserved CPUs; have %q want %q", path, mask, expectedRPSCPUsMask)
 				}
 
 				By("verify RPS mask on physical network devices")
@@ -392,15 +394,17 @@ var _ = Describe("[rfe_id:27368][performance]", Ordered, func() {
 					"-regex", "/rootfs/sys/devices/pci.*",
 					"-type", "f",
 					"-name", "rps_cpus",
+					"-printf", "%p ",
 					"-exec", "cat", "{}", ";",
 				}
-				devsRPS, err = nodes.ExecCommandOnNode(cmd, &node)
+				devsRPSContent, err = nodes.ExecCommandOnNode(cmd, &node)
 				Expect(err).ToNot(HaveOccurred(), "failed to exec command %q on node %q", cmd, node.Name)
 
-				for _, devRPS := range strings.Split(devsRPS, "\n") {
-					rpsCPUs, err = components.CPUMaskToCPUSet(devRPS)
+				devsRPSMap = makeDevRPSMap(devsRPSContent)
+				for path, mask := range devsRPSMap {
+					rpsCPUs, err = components.CPUMaskToCPUSet(mask)
 					Expect(err).ToNot(HaveOccurred())
-					Expect(rpsCPUs.Equals(expectedPhysRPSCPUs)).To(BeTrue(), "a host device rps mask is different than expected; have %q want %q", devRPS, expectedPhyRPSCPUsMask)
+					Expect(rpsCPUs.Equals(expectedPhysRPSCPUs)).To(BeTrue(), "a host physical device: %q rps mask is different than expected; have %q want %q", path, mask, expectedPhyRPSCPUsMask)
 				}
 			}
 		})
@@ -1424,3 +1428,16 @@ func validateTunedActiveProfile(wrknodes []corev1.Node) {
 			fmt.Sprintf("active_profile is not set to %s. %v", activeProfileName, err))
 	}
 }
+
+// makeDevRPSMap converts the find command output where each line has the following pattern:
+// '/rootfs/sys/devices/virtual/net/<dev-id>/queues/rx-<queue-number>/rps_cpus <rps-mask>'
+// into a map of devices with their corresponding rps mask
+func makeDevRPSMap(content string) map[string]string {
+	devRPSMap := make(map[string]string)
+	for _, line := range strings.Split(content, "\n") {
+		s := strings.Split(line, " ")
+		path, mask := s[0], s[1]
+		devRPSMap[path] = mask
+	}
+	return devRPSMap
+}