forked from ccfos/huatuo
97 lines
2.4 KiB
Go
97 lines
2.4 KiB
Go
// Copyright 2025 The HuaTuo 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.
|
|
|
|
//go:build !didi
|
|
|
|
package bpf
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"encoding/binary"
|
|
"fmt"
|
|
"os"
|
|
"time"
|
|
|
|
"huatuo-bamai/pkg/types"
|
|
|
|
"github.com/cilium/ebpf"
|
|
"github.com/cilium/ebpf/perf"
|
|
"github.com/pkg/errors"
|
|
)
|
|
|
|
// perfEventReader reads the eBPF perf_event_array.
|
|
type perfEventReader struct {
|
|
ctx context.Context
|
|
rd *perf.Reader
|
|
cancelCtx context.CancelFunc
|
|
}
|
|
|
|
// _ is a type assertion
|
|
var _ PerfEventReader = (*perfEventReader)(nil)
|
|
|
|
// newPerfEventReader creates a new perfEventReader.
|
|
func newPerfEventReader(ctx context.Context, array *ebpf.Map, perCPUBuffer int) (PerfEventReader, error) {
|
|
rd, err := perf.NewReader(array, perCPUBuffer)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("can't create the perf event reader: %w", err)
|
|
}
|
|
|
|
readerCtx, cancel := context.WithCancel(ctx)
|
|
return &perfEventReader{ctx: readerCtx, rd: rd, cancelCtx: cancel}, nil
|
|
}
|
|
|
|
// Close the perfEventReader.
|
|
func (r *perfEventReader) Close() error {
|
|
r.cancelCtx()
|
|
r.rd.Close()
|
|
|
|
return nil
|
|
}
|
|
|
|
// ReadInto reads the eBPF perf_event into pdata.
|
|
func (r *perfEventReader) ReadInto(pdata any) error {
|
|
for {
|
|
select {
|
|
case <-r.ctx.Done():
|
|
return types.ErrExitByCancelCtx
|
|
default:
|
|
// set the poll deadline 100ms
|
|
r.rd.SetDeadline(time.Now().Add(100 * time.Millisecond))
|
|
|
|
// read the event
|
|
record, err := r.rd.Read()
|
|
if err != nil {
|
|
if errors.Is(err, perf.ErrClosed) { // Close
|
|
return fmt.Errorf("perfEventReader is closed: %w", types.ErrExitByCancelCtx)
|
|
} else if errors.Is(err, os.ErrDeadlineExceeded) { // poll deadline
|
|
continue
|
|
}
|
|
return fmt.Errorf("failed to read the event: %w", err)
|
|
}
|
|
|
|
if record.LostSamples != 0 {
|
|
continue
|
|
}
|
|
|
|
// parse the event
|
|
if err := binary.Read(bytes.NewBuffer(record.RawSample), binary.NativeEndian, pdata); err != nil {
|
|
return fmt.Errorf("failed to parse the event: %w", err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
}
|
|
}
|