[VOL-4291] Rw-core updates for gRPC migration

Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/prometheus/procfs/mountstats.go b/vendor/github.com/prometheus/procfs/mountstats.go
index 35b2ef3..f7a828b 100644
--- a/vendor/github.com/prometheus/procfs/mountstats.go
+++ b/vendor/github.com/prometheus/procfs/mountstats.go
@@ -186,6 +186,8 @@
 	CumulativeTotalResponseMilliseconds uint64
 	// Duration from when a request was enqueued to when it was completely handled.
 	CumulativeTotalRequestMilliseconds uint64
+	// The count of operations that complete with tk_status < 0.  These statuses usually indicate error conditions.
+	Errors uint64
 }
 
 // A NFSTransportStats contains statistics for the NFS mount RPC requests and
@@ -336,12 +338,12 @@
 		if len(ss) == 0 {
 			break
 		}
-		if len(ss) < 2 {
-			return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
-		}
 
 		switch ss[0] {
 		case fieldOpts:
+			if len(ss) < 2 {
+				return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
+			}
 			if stats.Opts == nil {
 				stats.Opts = map[string]string{}
 			}
@@ -354,6 +356,9 @@
 				}
 			}
 		case fieldAge:
+			if len(ss) < 2 {
+				return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
+			}
 			// Age integer is in seconds
 			d, err := time.ParseDuration(ss[1] + "s")
 			if err != nil {
@@ -362,6 +367,9 @@
 
 			stats.Age = d
 		case fieldBytes:
+			if len(ss) < 2 {
+				return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
+			}
 			bstats, err := parseNFSBytesStats(ss[1:])
 			if err != nil {
 				return nil, err
@@ -369,6 +377,9 @@
 
 			stats.Bytes = *bstats
 		case fieldEvents:
+			if len(ss) < 2 {
+				return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
+			}
 			estats, err := parseNFSEventsStats(ss[1:])
 			if err != nil {
 				return nil, err
@@ -494,8 +505,8 @@
 // line is reached.
 func parseNFSOperationStats(s *bufio.Scanner) ([]NFSOperationStats, error) {
 	const (
-		// Number of expected fields in each per-operation statistics set
-		numFields = 9
+		// Minimum number of expected fields in each per-operation statistics set
+		minFields = 9
 	)
 
 	var ops []NFSOperationStats
@@ -508,12 +519,12 @@
 			break
 		}
 
-		if len(ss) != numFields {
+		if len(ss) < minFields {
 			return nil, fmt.Errorf("invalid NFS per-operations stats: %v", ss)
 		}
 
 		// Skip string operation name for integers
-		ns := make([]uint64, 0, numFields-1)
+		ns := make([]uint64, 0, minFields-1)
 		for _, st := range ss[1:] {
 			n, err := strconv.ParseUint(st, 10, 64)
 			if err != nil {
@@ -523,7 +534,7 @@
 			ns = append(ns, n)
 		}
 
-		ops = append(ops, NFSOperationStats{
+		opStats := NFSOperationStats{
 			Operation:                           strings.TrimSuffix(ss[0], ":"),
 			Requests:                            ns[0],
 			Transmissions:                       ns[1],
@@ -533,7 +544,13 @@
 			CumulativeQueueMilliseconds:         ns[5],
 			CumulativeTotalResponseMilliseconds: ns[6],
 			CumulativeTotalRequestMilliseconds:  ns[7],
-		})
+		}
+
+		if len(ns) > 8 {
+			opStats.Errors = ns[8]
+		}
+
+		ops = append(ops, opStats)
 	}
 
 	return ops, s.Err()