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018fb8e6d9
ForceGosched() performs bad when GOMAXPROCS>1. When GOMAXPROCS=1, it
could promise that other goroutines run long enough
because it always yield the processor to other goroutines. But it cannot
yield processor to goroutine running on other processors. So when
GOMAXPROCS>1, the yield may finish when goroutine on the other
processor just runs for little time.
Here is a test to confirm the case:
```
package main
import (
"fmt"
"runtime"
"testing"
)
func ForceGosched() {
// possibility enough to sched up to 10 go routines.
for i := 0; i < 10000; i++ {
runtime.Gosched()
}
}
var d int
func loop(c chan struct{}) {
for {
select {
case <-c:
for i := 0; i < 1000; i++ {
fmt.Sprintf("come to time %d", i)
}
d++
}
}
}
func TestLoop(t *testing.T) {
c := make(chan struct{}, 1)
go loop(c)
c <- struct{}{}
ForceGosched()
if d != 1 {
t.Fatal("d is not incremented")
}
}
```
`go test -v -race` runs well, but `GOMAXPROCS=2 go test -v -race` fails.
Change the functionality to waiting for schedule to happen.
47 lines
1.1 KiB
Go
47 lines
1.1 KiB
Go
// Copyright 2015 CoreOS, Inc.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package testutil
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import (
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"net/url"
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"testing"
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"time"
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)
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// TODO: improve this when we are able to know the schedule or status of target go-routine.
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func WaitSchedule() {
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time.Sleep(3 * time.Millisecond)
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}
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func MustNewURLs(t *testing.T, urls []string) []url.URL {
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if urls == nil {
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return nil
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}
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var us []url.URL
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for _, url := range urls {
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u := MustNewURL(t, url)
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us = append(us, *u)
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}
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return us
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}
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func MustNewURL(t *testing.T, s string) *url.URL {
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u, err := url.Parse(s)
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if err != nil {
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t.Fatalf("parse %v error: %v", s, err)
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}
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return u
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}
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