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-rw-r--r--pkg/tmutex/tmutex_test.go257
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diff --git a/pkg/tmutex/tmutex_test.go b/pkg/tmutex/tmutex_test.go
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index ce34c7962..000000000
--- a/pkg/tmutex/tmutex_test.go
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@@ -1,257 +0,0 @@
-// Copyright 2018 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 tmutex
-
-import (
- "fmt"
- "runtime"
- "sync"
- "sync/atomic"
- "testing"
- "time"
-)
-
-func TestBasicLock(t *testing.T) {
- var m Mutex
- m.Init()
-
- m.Lock()
-
- // Try blocking lock the mutex from a different goroutine. This must
- // not block because the mutex is held.
- ch := make(chan struct{}, 1)
- go func() {
- m.Lock()
- ch <- struct{}{}
- m.Unlock()
- ch <- struct{}{}
- }()
-
- select {
- case <-ch:
- t.Fatalf("Lock succeeded on locked mutex")
- case <-time.After(100 * time.Millisecond):
- }
-
- // Unlock the mutex and make sure that the goroutine waiting on Lock()
- // unblocks and succeeds.
- m.Unlock()
-
- select {
- case <-ch:
- case <-time.After(100 * time.Millisecond):
- t.Fatalf("Lock failed to acquire unlocked mutex")
- }
-
- // Make sure we can lock and unlock again.
- m.Lock()
- m.Unlock()
-}
-
-func TestTryLock(t *testing.T) {
- var m Mutex
- m.Init()
-
- // Try to lock. It should succeed.
- if !m.TryLock() {
- t.Fatalf("TryLock failed on unlocked mutex")
- }
-
- // Try to lock again, it should now fail.
- if m.TryLock() {
- t.Fatalf("TryLock succeeded on locked mutex")
- }
-
- // Try blocking lock the mutex from a different goroutine. This must
- // not block because the mutex is held.
- ch := make(chan struct{}, 1)
- go func() {
- m.Lock()
- ch <- struct{}{}
- m.Unlock()
- }()
-
- select {
- case <-ch:
- t.Fatalf("Lock succeeded on locked mutex")
- case <-time.After(100 * time.Millisecond):
- }
-
- // Unlock the mutex and make sure that the goroutine waiting on Lock()
- // unblocks and succeeds.
- m.Unlock()
-
- select {
- case <-ch:
- case <-time.After(100 * time.Millisecond):
- t.Fatalf("Lock failed to acquire unlocked mutex")
- }
-}
-
-func TestMutualExclusion(t *testing.T) {
- var m Mutex
- m.Init()
-
- // Test mutual exclusion by running "gr" goroutines concurrently, and
- // have each one increment a counter "iters" times within the critical
- // section established by the mutex.
- //
- // If at the end the counter is not gr * iters, then we know that
- // goroutines ran concurrently within the critical section.
- //
- // If one of the goroutines doesn't complete, it's likely a bug that
- // causes to it to wait forever.
- const gr = 1000
- const iters = 100000
- v := 0
- var wg sync.WaitGroup
- for i := 0; i < gr; i++ {
- wg.Add(1)
- go func() {
- for j := 0; j < iters; j++ {
- m.Lock()
- v++
- m.Unlock()
- }
- wg.Done()
- }()
- }
-
- wg.Wait()
-
- if v != gr*iters {
- t.Fatalf("Bad count: got %v, want %v", v, gr*iters)
- }
-}
-
-func TestMutualExclusionWithTryLock(t *testing.T) {
- var m Mutex
- m.Init()
-
- // Similar to the previous, with the addition of some goroutines that
- // only increment the count if TryLock succeeds.
- const gr = 1000
- const iters = 100000
- total := int64(gr * iters)
- var tryTotal int64
- v := int64(0)
- var wg sync.WaitGroup
- for i := 0; i < gr; i++ {
- wg.Add(2)
- go func() {
- for j := 0; j < iters; j++ {
- m.Lock()
- v++
- m.Unlock()
- }
- wg.Done()
- }()
- go func() {
- local := int64(0)
- for j := 0; j < iters; j++ {
- if m.TryLock() {
- v++
- m.Unlock()
- local++
- }
- }
- atomic.AddInt64(&tryTotal, local)
- wg.Done()
- }()
- }
-
- wg.Wait()
-
- t.Logf("tryTotal = %d", tryTotal)
- total += tryTotal
-
- if v != total {
- t.Fatalf("Bad count: got %v, want %v", v, total)
- }
-}
-
-// BenchmarkTmutex is equivalent to TestMutualExclusion, with the following
-// differences:
-//
-// - The number of goroutines is variable, with the maximum value depending on
-// GOMAXPROCS.
-//
-// - The number of iterations per benchmark is controlled by the benchmarking
-// framework.
-//
-// - Care is taken to ensure that all goroutines participating in the benchmark
-// have been created before the benchmark begins.
-func BenchmarkTmutex(b *testing.B) {
- for n, max := 1, 4*runtime.GOMAXPROCS(0); n > 0 && n <= max; n *= 2 {
- b.Run(fmt.Sprintf("%d", n), func(b *testing.B) {
- var m Mutex
- m.Init()
-
- var ready sync.WaitGroup
- begin := make(chan struct{})
- var end sync.WaitGroup
- for i := 0; i < n; i++ {
- ready.Add(1)
- end.Add(1)
- go func() {
- ready.Done()
- <-begin
- for j := 0; j < b.N; j++ {
- m.Lock()
- m.Unlock()
- }
- end.Done()
- }()
- }
-
- ready.Wait()
- b.ResetTimer()
- close(begin)
- end.Wait()
- })
- }
-}
-
-// BenchmarkSyncMutex is equivalent to BenchmarkTmutex, but uses sync.Mutex as
-// a comparison point.
-func BenchmarkSyncMutex(b *testing.B) {
- for n, max := 1, 4*runtime.GOMAXPROCS(0); n > 0 && n <= max; n *= 2 {
- b.Run(fmt.Sprintf("%d", n), func(b *testing.B) {
- var m sync.Mutex
-
- var ready sync.WaitGroup
- begin := make(chan struct{})
- var end sync.WaitGroup
- for i := 0; i < n; i++ {
- ready.Add(1)
- end.Add(1)
- go func() {
- ready.Done()
- <-begin
- for j := 0; j < b.N; j++ {
- m.Lock()
- m.Unlock()
- }
- end.Done()
- }()
- }
-
- ready.Wait()
- b.ResetTimer()
- close(begin)
- end.Wait()
- })
- }
-}