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-rw-r--r--vendor/github.com/prometheus/procfs/schedstat.go118
1 files changed, 118 insertions, 0 deletions
diff --git a/vendor/github.com/prometheus/procfs/schedstat.go b/vendor/github.com/prometheus/procfs/schedstat.go
new file mode 100644
index 000000000..a4c4089ac
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/schedstat.go
@@ -0,0 +1,118 @@
+// Copyright 2019 The Prometheus 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 procfs
+
+import (
+ "bufio"
+ "errors"
+ "os"
+ "regexp"
+ "strconv"
+)
+
+var (
+ cpuLineRE = regexp.MustCompile(`cpu(\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+) (\d+)`)
+ procLineRE = regexp.MustCompile(`(\d+) (\d+) (\d+)`)
+)
+
+// Schedstat contains scheduler statistics from /proc/schedstat
+//
+// See
+// https://www.kernel.org/doc/Documentation/scheduler/sched-stats.txt
+// for a detailed description of what these numbers mean.
+//
+// Note the current kernel documentation claims some of the time units are in
+// jiffies when they are actually in nanoseconds since 2.6.23 with the
+// introduction of CFS. A fix to the documentation is pending. See
+// https://lore.kernel.org/patchwork/project/lkml/list/?series=403473
+type Schedstat struct {
+ CPUs []*SchedstatCPU
+}
+
+// SchedstatCPU contains the values from one "cpu<N>" line
+type SchedstatCPU struct {
+ CPUNum string
+
+ RunningNanoseconds uint64
+ WaitingNanoseconds uint64
+ RunTimeslices uint64
+}
+
+// ProcSchedstat contains the values from /proc/<pid>/schedstat
+type ProcSchedstat struct {
+ RunningNanoseconds uint64
+ WaitingNanoseconds uint64
+ RunTimeslices uint64
+}
+
+// Schedstat reads data from /proc/schedstat
+func (fs FS) Schedstat() (*Schedstat, error) {
+ file, err := os.Open(fs.proc.Path("schedstat"))
+ if err != nil {
+ return nil, err
+ }
+ defer file.Close()
+
+ stats := &Schedstat{}
+ scanner := bufio.NewScanner(file)
+
+ for scanner.Scan() {
+ match := cpuLineRE.FindStringSubmatch(scanner.Text())
+ if match != nil {
+ cpu := &SchedstatCPU{}
+ cpu.CPUNum = match[1]
+
+ cpu.RunningNanoseconds, err = strconv.ParseUint(match[8], 10, 64)
+ if err != nil {
+ continue
+ }
+
+ cpu.WaitingNanoseconds, err = strconv.ParseUint(match[9], 10, 64)
+ if err != nil {
+ continue
+ }
+
+ cpu.RunTimeslices, err = strconv.ParseUint(match[10], 10, 64)
+ if err != nil {
+ continue
+ }
+
+ stats.CPUs = append(stats.CPUs, cpu)
+ }
+ }
+
+ return stats, nil
+}
+
+func parseProcSchedstat(contents string) (stats ProcSchedstat, err error) {
+ match := procLineRE.FindStringSubmatch(contents)
+
+ if match != nil {
+ stats.RunningNanoseconds, err = strconv.ParseUint(match[1], 10, 64)
+ if err != nil {
+ return
+ }
+
+ stats.WaitingNanoseconds, err = strconv.ParseUint(match[2], 10, 64)
+ if err != nil {
+ return
+ }
+
+ stats.RunTimeslices, err = strconv.ParseUint(match[3], 10, 64)
+ return
+ }
+
+ err = errors.New("could not parse schedstat")
+ return
+}