trace: handle end-of-generation in flight recorder
CL 693398 introduced an end-of-generation signal, but the x/exp flight
recorder wasn't updated to handle it.
Luckily, we can do something trivial and just pass it through, since the
old way still works, so we don't need to add full support.
Fixes golang/go#75085.
Change-Id: I2aeb723dc727eb308004140d04ef3e4e1c1b66b9
Reviewed-on: https://go-review.googlesource.com/c/exp/+/697417
Auto-Submit: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
diff --git a/trace/flightrecorder.go b/trace/flightrecorder.go
index 5cc7bb6..17d5d57 100644
--- a/trace/flightrecorder.go
+++ b/trace/flightrecorder.go
@@ -151,6 +151,9 @@
if err != nil {
return len(p) - rd.Len(), err
}
+ if b.isEndOfGeneration() {
+ gen = r.active.gen
+ }
// Check if we're entering a new generation.
if r.active.gen != 0 && r.active.gen+1 == gen {
@@ -200,18 +203,20 @@
}
// Append the batch to the current generation.
- if r.active.gen == 0 {
- r.active.gen = gen
+ if !b.isEndOfGeneration() {
+ if r.active.gen == 0 {
+ r.active.gen = gen
+ }
+ if r.active.minTime == 0 || r.active.minTime > b.time {
+ r.active.minTime = b.time
+ }
+ r.active.size += 1
+ r.active.size += uvarintSize(gen)
+ r.active.size += uvarintSize(uint64(b.m))
+ r.active.size += uvarintSize(uint64(b.time))
+ r.active.size += uvarintSize(uint64(len(b.data)))
+ r.active.size += len(b.data)
}
- if r.active.minTime == 0 || r.active.minTime > b.time {
- r.active.minTime = b.time
- }
- r.active.size += 1
- r.active.size += uvarintSize(gen)
- r.active.size += uvarintSize(uint64(b.m))
- r.active.size += uvarintSize(uint64(b.time))
- r.active.size += uvarintSize(uint64(len(b.data)))
- r.active.size += len(b.data)
r.active.batches = append(r.active.batches, b)
return len(p) - rd.Len(), nil
@@ -322,23 +327,26 @@
// Write all the data.
for _, gen := range gens {
for _, batch := range gen.batches {
- // Rewrite the batch header event with four arguments: gen, M ID, timestamp, and data length.
- n, err := w.Write([]byte{byte(tracev2.EvEventBatch)})
- total += n
- if err != nil {
- return total, err
- }
- if err := writeUvarint(gen.gen); err != nil {
- return total, err
- }
- if err := writeUvarint(uint64(batch.m)); err != nil {
- return total, err
- }
- if err := writeUvarint(uint64(batch.time)); err != nil {
- return total, err
- }
- if err := writeUvarint(uint64(len(batch.data))); err != nil {
- return total, err
+ var n int
+ if !batch.isEndOfGeneration() {
+ // Rewrite the batch header event with four arguments: gen, M ID, timestamp, and data length.
+ n, err := w.Write([]byte{byte(tracev2.EvEventBatch)})
+ total += n
+ if err != nil {
+ return total, err
+ }
+ if err := writeUvarint(gen.gen); err != nil {
+ return total, err
+ }
+ if err := writeUvarint(uint64(batch.m)); err != nil {
+ return total, err
+ }
+ if err := writeUvarint(uint64(batch.time)); err != nil {
+ return total, err
+ }
+ if err := writeUvarint(uint64(len(batch.data))); err != nil {
+ return total, err
+ }
}
// Write batch data.
