meminfo: add Percpu field (prometheus#588)

Signed-off-by: wangqing <[email protected]>
Co-authored-by: wangqing <[email protected]>

Author: wangqingfree

meminfo.go

@@ -126,6 +126,7 @@ type Meminfo struct {
 	VmallocUsed *uint64
 	// largest contiguous block of vmalloc area which is free
 	VmallocChunk      *uint64
+	Percpu            *uint64
 	HardwareCorrupted *uint64
 	AnonHugePages     *uint64
 	ShmemHugePages    *uint64
@@ -178,6 +179,7 @@ type Meminfo struct {
 	VmallocTotalBytes      *uint64
 	VmallocUsedBytes       *uint64
 	VmallocChunkBytes      *uint64
+	PercpuBytes            *uint64
 	HardwareCorruptedBytes *uint64
 	AnonHugePagesBytes     *uint64
 	ShmemHugePagesBytes    *uint64
@@ -339,6 +341,9 @@ func parseMemInfo(r io.Reader) (*Meminfo, error) {
 		case "VmallocChunk:":
 			m.VmallocChunk = &val
 			m.VmallocChunkBytes = &valBytes
+		case "Percpu:":
+			m.Percpu = &val
+			m.PercpuBytes = &valBytes
 		case "HardwareCorrupted:":
 			m.HardwareCorrupted = &val
 			m.HardwareCorruptedBytes = &valBytes

meminfo_test.go

@@ -53,6 +53,7 @@ func TestMeminfo(t *testing.T) {
 		VmallocTotal:      newuint64(34359738367),
 		VmallocUsed:       newuint64(36596),
 		VmallocChunk:      newuint64(34359637840),
+		Percpu:            newuint64(26176),
 		HardwareCorrupted: newuint64(0),
 		AnonHugePages:     newuint64(12288),
 		HugePagesTotal:    newuint64(0),
@@ -96,6 +97,7 @@ func TestMeminfo(t *testing.T) {
 		VmallocTotalBytes:      newuint64(35184372087808),
 		VmallocUsedBytes:       newuint64(37474304),
 		VmallocChunkBytes:      newuint64(35184269148160),
+		PercpuBytes:            newuint64(26804224),
 		HardwareCorruptedBytes: newuint64(0),
 		AnonHugePagesBytes:     newuint64(12582912),
 		HugepagesizeBytes:      newuint64(2097152),

testdata/fixtures.ttar

@@ -2317,7 +2317,7 @@ unused devices: <none>
 Mode: 644
 # ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 Path: fixtures/proc/meminfo
-Lines: 42
+Lines: 43
 MemTotal:       15666184 kB
 MemFree:          440324 kB
 Buffers:         1020128 kB
@@ -2351,6 +2351,7 @@ Committed_AS:     530844 kB
 VmallocTotal:   34359738367 kB
 VmallocUsed:       36596 kB
 VmallocChunk:   34359637840 kB
+Percpu:            26176 kB
 HardwareCorrupted:     0 kB
 AnonHugePages:     12288 kB
 HugePages_Total:       0