99 lines
2.4 KiB
Go
99 lines
2.4 KiB
Go
|
// +build linux
|
||
|
|
|
||
|
|
package perf
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"strconv"
|
||
|
|
"strings"
|
||
|
|
"unsafe"
|
||
|
|
|
||
|
|
"golang.org/x/sys/unix"
|
||
|
|
)
|
||
|
|
|
||
|
|
const (
|
||
|
|
// PERF_TYPE_TRACEPOINT is a kernel tracepoint.
|
||
|
|
PERF_TYPE_TRACEPOINT = 2
|
||
|
|
)
|
||
|
|
|
||
|
|
// AvailableEvents returns the list of available events.
|
||
|
|
func AvailableEvents() (map[string][]string, error) {
|
||
|
|
events := map[string][]string{}
|
||
|
|
rawEvents, err := fileToStrings(TracingDir + "/available_events")
|
||
|
|
// Events are colon delimited by type so parse the type and add sub
|
||
|
|
// events appropriately.
|
||
|
|
if err != nil {
|
||
|
|
return events, err
|
||
|
|
}
|
||
|
|
for _, rawEvent := range rawEvents {
|
||
|
|
splits := strings.Split(rawEvent, ":")
|
||
|
|
if len(splits) <= 1 {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
eventTypeEvents, found := events[splits[0]]
|
||
|
|
if found {
|
||
|
|
events[splits[0]] = append(eventTypeEvents, splits[1])
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
events[splits[0]] = []string{splits[1]}
|
||
|
|
}
|
||
|
|
return events, err
|
||
|
|
}
|
||
|
|
|
||
|
|
// AvailableTracers returns the list of available tracers.
|
||
|
|
func AvailableTracers() ([]string, error) {
|
||
|
|
return fileToStrings(TracingDir + "/available_tracers")
|
||
|
|
}
|
||
|
|
|
||
|
|
// CurrentTracer returns the current tracer.
|
||
|
|
func CurrentTracer() (string, error) {
|
||
|
|
res, err := fileToStrings(TracingDir + "/current_tracer")
|
||
|
|
return res[0], err
|
||
|
|
}
|
||
|
|
|
||
|
|
// getTracepointConfig is used to get the configuration for a trace event.
|
||
|
|
func getTracepointConfig(kind, event string) (uint64, error) {
|
||
|
|
res, err := fileToStrings(TracingDir + fmt.Sprintf("/events/%s/%s/id", kind, event))
|
||
|
|
if err != nil {
|
||
|
|
return 0, err
|
||
|
|
}
|
||
|
|
return strconv.ParseUint(res[0], 10, 64)
|
||
|
|
}
|
||
|
|
|
||
|
|
// ProfileTracepoint is used to profile a kernel tracepoint event. Events can
|
||
|
|
// be listed with `perf list` for Tracepoint Events or in the
|
||
|
|
// /sys/kernel/debug/tracing/events directory with the kind being the directory
|
||
|
|
// and the event being the subdirectory.
|
||
|
|
func ProfileTracepoint(kind, event string, pid, cpu int, opts ...int) (BPFProfiler, error) {
|
||
|
|
config, err := getTracepointConfig(kind, event)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
eventAttr := &unix.PerfEventAttr{
|
||
|
|
Type: PERF_TYPE_TRACEPOINT,
|
||
|
|
Config: config,
|
||
|
|
Size: uint32(unsafe.Sizeof(unix.PerfEventAttr{})),
|
||
|
|
Bits: unix.PerfBitDisabled | unix.PerfBitExcludeHv,
|
||
|
|
Read_format: unix.PERF_FORMAT_TOTAL_TIME_RUNNING | unix.PERF_FORMAT_TOTAL_TIME_ENABLED,
|
||
|
|
Sample_type: PERF_SAMPLE_IDENTIFIER,
|
||
|
|
}
|
||
|
|
var eventOps int
|
||
|
|
if len(opts) > 0 {
|
||
|
|
eventOps = opts[0]
|
||
|
|
}
|
||
|
|
fd, err := unix.PerfEventOpen(
|
||
|
|
eventAttr,
|
||
|
|
pid,
|
||
|
|
cpu,
|
||
|
|
-1,
|
||
|
|
eventOps,
|
||
|
|
)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
return &profiler{
|
||
|
|
fd: fd,
|
||
|
|
}, nil
|
||
|
|
}
|