Adding SR-IOV capability discovery to node-feature-discovery (#49)

* Adding SR-IOV capability discovery to node-feature-discovery

* SR-IOV capability discovery in NFD : code update after PR review
- using hostnetwork instead of volume mount in file node-feature-discovery-job.json.template
- iterating through network interfaces that are "up" in sources.go
- inserting logs in sources.go
- change in feature source name from "netid" to "network" in sources.go, README.md and main.go

*  Added code for labels sriov=true (sriov_totalvfs > 0) and sriov-configured=true (sriov_numvfs > 0)

* Code Refactored: Added Network package and network.go

README.md

@@ -41,7 +41,7 @@ node-feature-discovery.
   -h --help                   Show this screen.
   --version                   Output version and exit.
   --sources=<sources>         Comma separated list of feature sources.
-                              [Default: cpuid,rdt,pstate]
+                              [Default: cpuid,rdt,pstate,network]
   --no-publish                Do not publish discovered features to the
                               cluster-local Kubernetes API server.
   --label-whitelist=<pattern> Regular expression to filter label names to
@@ -57,6 +57,7 @@ The current set of feature sources are the following:
 - [CPUID][cpuid] for x86 CPU details
 - [Intel Resource Director Technology][intel-rdt]
 - [Intel P-State driver][intel-pstate]
+- Network
 
 ### Feature labels
 
@@ -77,7 +78,8 @@ the only label value published for features is the string `"true"`._
   "node.alpha.kubernetes-incubator.io/node-feature-discovery.version": "v0.1.0",
   "node.alpha.kubernetes-incubator.io/nfd-cpuid-<feature-name>": "true",
   "node.alpha.kubernetes-incubator.io/nfd-rdt-<feature-name>": "true",
-  "node.alpha.kubernetes-incubator.io/nfd-pstate-<feature-name>": "true"
+  "node.alpha.kubernetes-incubator.io/nfd-pstate-<feature-name>": "true",
+  "node.alpha.kubernetes-incubator.io/nfd-network-<feature-name>": "true"
 }
 ```
 
@@ -110,6 +112,12 @@ such as restricting discovered features with the --label-whitelist option._
 | SSE4.2         | Streaming SIMD Extensions 4.2 (SSE4.2)
 | SGX            | Software Guard Extensions (SGX)
 
+### Network Features
+
+| Feature name   | Description                                                                         |
+| :------------: | :---------------------------------------------------------------------------------: |
+| [SRIOV][sriov] | Single Root Input/Output Virtualization (SR-IOV) enabled Network Interface Card
+
 ## Getting started
 ### System requirements
 
@@ -129,7 +137,7 @@ repo that demonstrates how to deploy the job to unlabeled nodes.
 
 The discovery script will launch a job on each unlabeled node in the
 cluster. When the job runs, it contacts the Kubernetes API server to add labels
-to the node to advertise hardware features (initially, from `cpuid`, RDT and p-state).
+to the node to advertise hardware features (initially, from `cpuid`, RDT, p-state and network).
 
 [![asciicast](https://asciinema.org/a/11wir751y89617oemwnsgli4a.png)](https://asciinema.org/a/11wir751y89617oemwnsgli4a)
 
@@ -226,6 +234,7 @@ A demo on the benefits of using node feature discovery can be found in [demo](de
 [cpuid]: http://man7.org/linux/man-pages/man4/cpuid.4.html
 [intel-rdt]: http://www.intel.com/content/www/us/en/architecture-and-technology/resource-director-technology.html
 [intel-pstate]: https://www.kernel.org/doc/Documentation/cpu-freq/intel-pstate.txt
+[sriov]: http://www.intel.com/content/www/us/en/pci-express/pci-sig-sr-iov-primer-sr-iov-technology-paper.html
 [docker-down]: https://docs.docker.com/engine/installation
 [golang-down]: https://golang.org/dl
 [gcc-down]: https://gcc.gnu.org

main.go

@@ -10,6 +10,7 @@ import (
 	"github.com/kubernetes-incubator/node-feature-discovery/source"
 	"github.com/kubernetes-incubator/node-feature-discovery/source/cpuid"
 	"github.com/kubernetes-incubator/node-feature-discovery/source/fake"
+	"github.com/kubernetes-incubator/node-feature-discovery/source/network"
 	"github.com/kubernetes-incubator/node-feature-discovery/source/panic_fake"
 	"github.com/kubernetes-incubator/node-feature-discovery/source/pstate"
 	"github.com/kubernetes-incubator/node-feature-discovery/source/rdt"
@@ -110,7 +111,7 @@ func argsParse(argv []string) (noPublish bool, sourcesArg []string, whiteListArg
   -h --help                   Show this screen.
   --version                   Output version and exit.
   --sources=<sources>         Comma separated list of feature sources.
-                              [Default: cpuid,rdt,pstate]
+                              [Default: cpuid,rdt,pstate,network]
   --no-publish                Do not publish discovered features to the
                               cluster-local Kubernetes API server.
   --label-whitelist=<pattern> Regular expression to filter label names to
@@ -145,6 +146,7 @@ func configureParameters(sourcesArg []string, whiteListArg string) (sources []so
 		cpuid.Source{},
 		rdt.Source{},
 		pstate.Source{},
+		network.Source{},
 		fake.Source{},
 		panic_fake.Source{},
 	}

node-feature-discovery-job.json.template

@@ -17,6 +17,7 @@
         }
       },
       "spec": {
+	"hostNetwork": true,
         "containers": [
           {
             "env": [
@@ -41,7 +42,7 @@
             "name": "node-feature-discovery",
             "ports": [
               {
-                "containerPort": 2233,
+                "containerPort": 7156,
                 "hostPort": 7156
               }
             ]

source/network/network.go

@@ -0,0 +1,83 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package network
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"strconv"
+	"strings"
+	"github.com/golang/glog"
+)
+
+// Source implements FeatureSource.
+type Source struct{}
+
+func (s Source) Name() string { return "network" }
+
+// returns feature names sriov-configured and sriov if SR-IOV capable NICs are present and/or SR-IOV virtual functions are configured on the node
+func (s Source) Discover() ([]string, error) {
+	features := []string{}
+	netInterfaces, err := net.Interfaces()
+	if err != nil {
+		return nil, fmt.Errorf("can't obtain the network interfaces details: %s", err.Error())
+	}
+	// iterating through network interfaces to obtain their respective number of virtual functions
+	for _, netInterface := range netInterfaces {
+		if strings.Contains(netInterface.Flags.String(), "up") && !strings.Contains(netInterface.Flags.String(), "loopback") {
+			totalVfsPath := "/sys/class/net/" + netInterface.Name + "/device/sriov_totalvfs"
+			totalBytes, err := ioutil.ReadFile(totalVfsPath)
+			if err != nil {
+				glog.Errorf("SR-IOV not supported for network interface: %s: %v", netInterface.Name, err)
+				continue
+			}
+			total := bytes.TrimSpace(totalBytes)
+			t, err := strconv.Atoi(string(total))
+			if err != nil {
+				glog.Errorf("Error in obtaining maximum supported number of virtual functions for network interface: %s: %v", netInterface.Name, err)
+				continue
+			}
+			if t > 0 {
+				glog.Infof("SR-IOV capability is detected on the network interface: %s", netInterface.Name)
+				glog.Infof("%d maximum supported number of virtual functions on network interface: %s", t, netInterface.Name)
+				features = append(features, "sriov")
+				numVfsPath := "/sys/class/net/" + netInterface.Name + "/device/sriov_numvfs"
+				numBytes, err := ioutil.ReadFile(numVfsPath)
+				if err != nil {
+					glog.Errorf("SR-IOV not configured for network interface: %s: %s", netInterface.Name, err)
+					continue
+				}
+				num := bytes.TrimSpace(numBytes)
+				n, err := strconv.Atoi(string(num))
+				if err != nil {
+					glog.Errorf("Error in obtaining the configured number of virtual functions for network interface: %s: %v", netInterface.Name, err)
+					continue
+				}
+				if n > 0 {
+					glog.Infof("%d virtual functions configured on network interface: %s", n, netInterface.Name)
+					features = append(features, "sriov-configured")
+					break
+				} else if n == 0 {
+					glog.Errorf("SR-IOV not configured on network interface: %s", netInterface.Name)
+				}
+			}
+		}
+	}
+	return features, nil
+}