Added support for CPUInfo for ARM on Linux kernels 3.8+

Fixes issue #294

Signed-off-by: kadern0 <kaderno@gmail.com>

Author: kadern0

cpuinfo.go

@@ -190,15 +190,26 @@ func parseCPUInfoARM(info []byte) ([]CPUInfo, error) {
 	scanner := bufio.NewScanner(bytes.NewReader(info))
 
 	firstLine := firstNonEmptyLine(scanner)
-	if !strings.HasPrefix(firstLine, "Processor") || !strings.Contains(firstLine, ":") {
+	match, _ := regexp.MatchString("^[Pp]rocessor", firstLine)
+	if !match || !strings.Contains(firstLine, ":") {
 		return nil, errors.New("invalid cpuinfo file: " + firstLine)
 	}
 	field := strings.SplitN(firstLine, ": ", 2)
-	commonCPUInfo := CPUInfo{VendorID: field[1]}
-
 	cpuinfo := []CPUInfo{}
-	i := -1
 	featuresLine := ""
+	commonCPUInfo := CPUInfo{}
+	i := 0
+	if field[0] == "Processor " {
+		commonCPUInfo = CPUInfo{VendorID: field[1]}
+		i = -1
+	} else {
+		v, err := strconv.ParseUint(field[1], 0, 32)
+		if err != nil {
+			return nil, err
+		}
+		firstcpu := CPUInfo{Processor: uint(v)}
+		cpuinfo = []CPUInfo{firstcpu}
+	}
 
 	for scanner.Scan() {
 		line := scanner.Text()
@@ -223,13 +234,16 @@ func parseCPUInfoARM(info []byte) ([]CPUInfo, error) {
 			cpuinfo[i].BogoMips = v
 		case "Features":
 			featuresLine = line
+		case "model name":
+			cpuinfo[i].ModelName = field[1]
 		}
 	}
 	fields := strings.SplitN(featuresLine, ": ", 2)
 	for i := range cpuinfo {
 		cpuinfo[i].Flags = strings.Fields(fields[1])
 	}
 	return cpuinfo, nil
+
 }
 
 func parseCPUInfoS390X(info []byte) ([]CPUInfo, error) {

cpuinfo_test.go

@@ -18,7 +18,7 @@ package procfs
 import "testing"
 
 const (
-	cpuinfoArm7 = `
+	cpuinfoArm7Legacy = `
 Processor : ARMv7 Processor rev 5 (v7l)
 processor : 0
 BogoMIPS : 2400.00
@@ -37,6 +37,51 @@ Hardware : sun8i
 Revision : 0000
 Serial : 5400503583203c3c040e`
 
+	cpuinfoArm7 = `
+processor : 0
+model name : ARMv7 Processor rev 3 (v7l)
+BogoMIPS : 108.00
+Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32
+CPU implementer : 0x41
+CPU architecture: 7
+CPU variant : 0x0
+CPU part : 0xd08
+CPU revision : 3
+
+processor : 1
+model name : ARMv7 Processor rev 3 (v7l)
+BogoMIPS : 108.00
+Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32
+CPU implementer : 0x41
+CPU architecture: 7
+CPU variant : 0x0
+CPU part : 0xd08
+CPU revision : 3
+
+processor : 2
+model name : ARMv7 Processor rev 3 (v7l)
+BogoMIPS : 108.00
+Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32
+CPU implementer : 0x41
+CPU architecture: 7
+CPU variant : 0x0
+CPU part : 0xd08
+CPU revision : 3
+
+processor : 3
+model name : ARMv7 Processor rev 3 (v7l)
+BogoMIPS : 108.00
+Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32
+CPU implementer : 0x41
+CPU architecture: 7
+CPU variant : 0x0
+CPU part : 0xd08
+CPU revision : 3
+
+Hardware : BCM2835
+Revision : c03111
+`
+
 	cpuinfoS390x = `
 vendor_id       : IBM/S390
 # processors    : 4
@@ -153,8 +198,8 @@ func TestCPUInfoX86(t *testing.T) {
 	}
 }
 
-func TestCPUInfoParseARM(t *testing.T) {
-	cpuinfo, err := parseCPUInfoARM([]byte(cpuinfoArm7))
+func TestCPUInfoParseARMLegacy(t *testing.T) {
+	cpuinfo, err := parseCPUInfoARM([]byte(cpuinfoArm7Legacy))
 	if err != nil || cpuinfo == nil {
 		t.Fatalf("unable to parse arm cpu info: %v", err)
 	}
@@ -169,6 +214,22 @@ func TestCPUInfoParseARM(t *testing.T) {
 	}
 }
 
+func TestCPUInfoParseARM(t *testing.T) {
+	cpuinfo, err := parseCPUInfoARM([]byte(cpuinfoArm7))
+	if err != nil || cpuinfo == nil {
+		t.Fatalf("unable to parse arm cpu info: %v", err)
+	}
+	if want, have := 4, len(cpuinfo); want != have {
+		t.Errorf("want number of processors %v, have %v", want, have)
+	}
+	if want, have := "ARMv7 Processor rev 3 (v7l)", cpuinfo[0].ModelName; want != have {
+		t.Errorf("want vendor %v, have %v", want, have)
+	}
+	if want, have := "thumb", cpuinfo[1].Flags[1]; want != have {
+		t.Errorf("want flag %v, have %v", want, have)
+	}
+}
+
 func TestCPUInfoParseS390X(t *testing.T) {
 	cpuinfo, err := parseCPUInfoS390X([]byte(cpuinfoS390x))
 	if err != nil || cpuinfo == nil {