82 lines
2.2 KiB
Go
82 lines
2.2 KiB
Go
// Copyright 2020 The gVisor 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 goid
|
|
|
|
import (
|
|
"runtime"
|
|
"sync"
|
|
"testing"
|
|
"time"
|
|
)
|
|
|
|
func TestUniquenessAndConsistency(t *testing.T) {
|
|
const (
|
|
numGoroutines = 5000
|
|
|
|
// maxID is not an intrinsic property of goroutine IDs; it is only a
|
|
// property of how the Go runtime currently assigns them. Future
|
|
// changes to the Go runtime may require that maxID be raised, or that
|
|
// assertions regarding it be removed entirely.
|
|
maxID = numGoroutines + 1000
|
|
)
|
|
|
|
var (
|
|
goidsMu sync.Mutex
|
|
goids = make(map[int64]struct{})
|
|
checkedWG sync.WaitGroup
|
|
exitCh = make(chan struct{})
|
|
)
|
|
for i := 0; i < numGoroutines; i++ {
|
|
checkedWG.Add(1)
|
|
go func() {
|
|
id := Get()
|
|
if id > maxID {
|
|
t.Errorf("observed unexpectedly large goroutine ID %d", id)
|
|
}
|
|
goidsMu.Lock()
|
|
if _, dup := goids[id]; dup {
|
|
t.Errorf("observed duplicate goroutine ID %d", id)
|
|
}
|
|
goids[id] = struct{}{}
|
|
goidsMu.Unlock()
|
|
checkedWG.Done()
|
|
for {
|
|
if curID := Get(); curID != id {
|
|
t.Errorf("goroutine ID changed from %d to %d", id, curID)
|
|
// Don't spam logs by repeating the check; wait quietly for
|
|
// the test to finish.
|
|
<-exitCh
|
|
return
|
|
}
|
|
// Check if the test is over.
|
|
select {
|
|
case <-exitCh:
|
|
return
|
|
default:
|
|
}
|
|
// Yield to other goroutines, and possibly migrate to another P.
|
|
runtime.Gosched()
|
|
}
|
|
}()
|
|
}
|
|
// Wait for all goroutines to perform uniqueness checks.
|
|
checkedWG.Wait()
|
|
// Wait for an additional second to allow goroutines to spin checking for
|
|
// ID consistency.
|
|
time.Sleep(time.Second)
|
|
// Request that all goroutines exit.
|
|
close(exitCh)
|
|
}
|