Revert "[rwmutex] Added new tests"

This reverts commit 8c0112889f.

Remove flaky tests.
This commit is contained in:
Fedor Korotkiy 2021-04-25 16:50:53 +03:00
parent 93127eb98d
commit eaf94562f0

View file

@ -2,12 +2,9 @@ package rwmutex
import (
"fmt"
"math/rand"
"runtime"
"sync"
"sync/atomic"
"testing"
"time"
)
func parallelReader(m *RWMutex, clocked, cunlock, cdone chan bool) {
@ -117,163 +114,3 @@ func TestRWMutex(t *testing.T) {
HammerRWMutex(10, 10, n)
HammerRWMutex(10, 5, n)
}
type CriticalSection struct {
mu sync.Mutex
readersCount, writersCount int
}
func (cs *CriticalSection) AddToVariable(value *int, count int) {
cs.mu.Lock()
*value += count
cs.mu.Unlock()
}
func (cs *CriticalSection) Reader(t *testing.T, duration time.Duration) {
cs.AddToVariable(&cs.readersCount, 1)
cs.Check(t)
time.Sleep(duration) // do some work
cs.AddToVariable(&cs.readersCount, -1)
}
func (cs *CriticalSection) Writer(t *testing.T, duration time.Duration) {
cs.AddToVariable(&cs.writersCount, 1)
cs.Check(t)
time.Sleep(duration) // do some work
cs.AddToVariable(&cs.writersCount, -1)
}
func (cs *CriticalSection) Check(t *testing.T) {
cs.mu.Lock()
defer cs.mu.Unlock()
if cs.writersCount > 1 {
t.Errorf("To much writers: %d", cs.writersCount)
}
if cs.writersCount == 1 && cs.readersCount > 0 {
t.Errorf("We have %d readers and %d writers", cs.readersCount, cs.writersCount)
}
}
func TestAFewReaders(t *testing.T) {
var wg sync.WaitGroup
readersCount := 100
rwm := New()
cs := new(CriticalSection)
ch := make(chan struct{})
wg.Add(readersCount)
for i := 0; i < readersCount; i++ {
go func() {
rwm.RLock()
cs.Reader(t, 20*time.Millisecond)
rwm.RUnlock()
defer wg.Done()
}()
}
go func() {
wg.Wait()
ch <- struct{}{}
}()
select {
case <-ch: //ok
case <-time.After(25 * time.Millisecond):
t.Error("too slow, your readers are blocked")
}
}
func TestAFewWriters(t *testing.T) {
var wg sync.WaitGroup
writersCount := 10
rwm := New()
cs := new(CriticalSection)
wg.Add(writersCount)
for i := 0; i < writersCount; i++ {
go func() {
rwm.Lock()
cs.Writer(t, 10*time.Millisecond)
rwm.Unlock()
defer wg.Done()
}()
}
wg.Wait()
}
func TestWriterAfterReaders(t *testing.T) {
var wg sync.WaitGroup
rwm := New()
cs := new(CriticalSection)
readersCount := 10
wg.Add(readersCount + 1)
for i := 0; i < readersCount; i++ {
go func() {
rwm.RLock()
cs.Reader(t, 100*time.Millisecond)
rwm.RUnlock()
defer wg.Done()
}()
}
time.Sleep(10 * time.Millisecond)
go func() {
rwm.Lock()
cs.Writer(t, 10*time.Millisecond)
rwm.Unlock()
defer wg.Done()
}()
wg.Wait()
}
func TestReadersAfterWriters(t *testing.T) {
var wg sync.WaitGroup
rwm := New()
cs := new(CriticalSection)
RWCount := 10
wg.Add(2 * RWCount)
for i := 0; i < RWCount; i++ {
go func() {
rwm.Lock()
cs.Writer(t, 100*time.Millisecond)
rwm.Unlock()
defer wg.Done()
}()
}
time.Sleep(20 * time.Millisecond)
for i := 0; i < RWCount; i++ {
go func() {
rwm.RLock()
cs.Reader(t, 10*time.Millisecond)
rwm.RUnlock()
defer wg.Done()
}()
}
wg.Wait()
}
func TestRWStress(t *testing.T) {
var wg sync.WaitGroup
rwm := New()
cs := new(CriticalSection)
RWCount := 20
for j := 0; j < 100; j++ {
wg.Add(2 * RWCount)
for i := 0; i < RWCount; i++ {
go func() {
time.Sleep(time.Duration(rand.Intn(5)) * time.Millisecond) // some delay
rwm.Lock()
cs.Writer(t, time.Millisecond)
rwm.Unlock()
defer wg.Done()
}()
go func() {
time.Sleep(time.Duration(rand.Intn(5)) * time.Millisecond) // some delay
rwm.RLock()
cs.Reader(t, time.Millisecond)
rwm.RUnlock()
defer wg.Done()
}()
}
wg.Wait()
}
}