Add perf exporter (#1274)

Signed-off-by: Daniel Hodges <hodges.daniel.scott@gmail.com>

vendor/github.com/hodgesds/perf-utils/hardware_profiler.go

@@ -0,0 +1,157 @@
+// +build linux
+
+package perf
+
+import (
+	"go.uber.org/multierr"
+	"golang.org/x/sys/unix"
+)
+
+type hardwareProfiler struct {
+	// map of perf counter type to file descriptor
+	profilers map[int]Profiler
+}
+
+// NewHardwareProfiler returns a new hardware profiler.
+func NewHardwareProfiler(pid, cpu int, opts ...int) HardwareProfiler {
+	profilers := map[int]Profiler{}
+
+	cpuCycleProfiler, err := NewCPUCycleProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_CPU_CYCLES] = cpuCycleProfiler
+	}
+
+	instrProfiler, err := NewInstrProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_INSTRUCTIONS] = instrProfiler
+	}
+
+	cacheRefProfiler, err := NewCacheRefProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_CACHE_REFERENCES] = cacheRefProfiler
+	}
+
+	cacheMissesProfiler, err := NewCacheMissesProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_CACHE_MISSES] = cacheMissesProfiler
+	}
+
+	branchInstrProfiler, err := NewBranchInstrProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = branchInstrProfiler
+	}
+
+	branchMissesProfiler, err := NewBranchMissesProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_BRANCH_MISSES] = branchMissesProfiler
+	}
+
+	busCyclesProfiler, err := NewBusCyclesProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_BUS_CYCLES] = busCyclesProfiler
+	}
+
+	stalledCyclesFrontProfiler, err := NewStalledCyclesFrontProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = stalledCyclesFrontProfiler
+	}
+
+	stalledCyclesBackProfiler, err := NewStalledCyclesBackProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = stalledCyclesBackProfiler
+	}
+
+	refCPUCyclesProfiler, err := NewRefCPUCyclesProfiler(pid, cpu, opts...)
+	if err == nil {
+		profilers[unix.PERF_COUNT_HW_REF_CPU_CYCLES] = refCPUCyclesProfiler
+	}
+
+	return &hardwareProfiler{
+		profilers: profilers,
+	}
+}
+
+// Start is used to start the HardwareProfiler.
+func (p *hardwareProfiler) Start() error {
+	if len(p.profilers) == 0 {
+		return ErrNoProfiler
+	}
+	var err error
+	for _, profiler := range p.profilers {
+		err = multierr.Append(err, profiler.Start())
+	}
+	return err
+}
+
+// Reset is used to reset the HardwareProfiler.
+func (p *hardwareProfiler) Reset() error {
+	var err error
+	for _, profiler := range p.profilers {
+		err = multierr.Append(err, profiler.Reset())
+	}
+	return err
+}
+
+// Stop is used to reset the HardwareProfiler.
+func (p *hardwareProfiler) Stop() error {
+	var err error
+	for _, profiler := range p.profilers {
+		err = multierr.Append(err, profiler.Stop())
+	}
+	return err
+}
+
+// Close is used to reset the HardwareProfiler.
+func (p *hardwareProfiler) Close() error {
+	var err error
+	for _, profiler := range p.profilers {
+		err = multierr.Append(err, profiler.Close())
+	}
+	return err
+}
+
+// Profile is used to read the HardwareProfiler HardwareProfile it returns an
+// error only if all profiles fail.
+func (p *hardwareProfiler) Profile() (*HardwareProfile, error) {
+	var err error
+	hwProfile := &HardwareProfile{}
+	for profilerType, profiler := range p.profilers {
+		profileVal, err2 := profiler.Profile()
+		err = multierr.Append(err, err2)
+		if err2 == nil {
+			if hwProfile.TimeEnabled == nil {
+				hwProfile.TimeEnabled = &profileVal.TimeEnabled
+			}
+			if hwProfile.TimeRunning == nil {
+				hwProfile.TimeRunning = &profileVal.TimeRunning
+			}
+			switch profilerType {
+			case unix.PERF_COUNT_HW_CPU_CYCLES:
+				hwProfile.CPUCycles = &profileVal.Value
+			case unix.PERF_COUNT_HW_INSTRUCTIONS:
+				hwProfile.Instructions = &profileVal.Value
+			case unix.PERF_COUNT_HW_CACHE_REFERENCES:
+				hwProfile.CacheRefs = &profileVal.Value
+			case unix.PERF_COUNT_HW_CACHE_MISSES:
+				hwProfile.CacheMisses = &profileVal.Value
+			case unix.PERF_COUNT_HW_BRANCH_INSTRUCTIONS:
+				hwProfile.BranchInstr = &profileVal.Value
+			case unix.PERF_COUNT_HW_BRANCH_MISSES:
+				hwProfile.BranchMisses = &profileVal.Value
+			case unix.PERF_COUNT_HW_BUS_CYCLES:
+				hwProfile.BusCycles = &profileVal.Value
+			case unix.PERF_COUNT_HW_STALLED_CYCLES_FRONTEND:
+				hwProfile.StalledCyclesFrontend = &profileVal.Value
+			case unix.PERF_COUNT_HW_STALLED_CYCLES_BACKEND:
+				hwProfile.StalledCyclesBackend = &profileVal.Value
+			case unix.PERF_COUNT_HW_REF_CPU_CYCLES:
+				hwProfile.RefCPUCycles = &profileVal.Value
+			}
+		}
+	}
+	if len(multierr.Errors(err)) == len(p.profilers) {
+		return nil, err
+	}
+
+	return hwProfile, nil
+}