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Diffstat (limited to 'pkg/sentry/vfs/mount_test.go')
-rw-r--r--pkg/sentry/vfs/mount_test.go465
1 files changed, 0 insertions, 465 deletions
diff --git a/pkg/sentry/vfs/mount_test.go b/pkg/sentry/vfs/mount_test.go
deleted file mode 100644
index f394d7483..000000000
--- a/pkg/sentry/vfs/mount_test.go
+++ /dev/null
@@ -1,465 +0,0 @@
-// Copyright 2019 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 vfs
-
-import (
- "fmt"
- "runtime"
- "sync"
- "testing"
-)
-
-func TestMountTableLookupEmpty(t *testing.T) {
- var mt mountTable
- mt.Init()
-
- parent := &Mount{}
- point := &Dentry{}
- if m := mt.Lookup(parent, point); m != nil {
- t.Errorf("empty mountTable lookup: got %p, wanted nil", m)
- }
-}
-
-func TestMountTableInsertLookup(t *testing.T) {
- var mt mountTable
- mt.Init()
-
- mount := &Mount{}
- mount.storeKey(&Mount{}, &Dentry{})
- mt.Insert(mount)
-
- if m := mt.Lookup(mount.parent(), mount.point()); m != mount {
- t.Errorf("mountTable positive lookup: got %p, wanted %p", m, mount)
- }
-
- otherParent := &Mount{}
- if m := mt.Lookup(otherParent, mount.point()); m != nil {
- t.Errorf("mountTable lookup with wrong mount parent: got %p, wanted nil", m)
- }
- otherPoint := &Dentry{}
- if m := mt.Lookup(mount.parent(), otherPoint); m != nil {
- t.Errorf("mountTable lookup with wrong mount point: got %p, wanted nil", m)
- }
-}
-
-// TODO: concurrent lookup/insertion/removal
-
-// must be powers of 2
-var benchNumMounts = []int{1 << 2, 1 << 5, 1 << 8}
-
-// For all of the following:
-//
-// - BenchmarkMountTableFoo tests usage pattern "Foo" for mountTable.
-//
-// - BenchmarkMountMapFoo tests usage pattern "Foo" for a
-// sync.RWMutex-protected map. (Mutator benchmarks do not use a RWMutex, since
-// mountTable also requires external synchronization between mutators.)
-//
-// - BenchmarkMountSyncMapFoo tests usage pattern "Foo" for a sync.Map.
-//
-// ParallelLookup is by far the most common and performance-sensitive operation
-// for this application. NegativeLookup is also important, but less so (only
-// relevant with multiple mount namespaces and significant differences in
-// mounts between them). Insertion and removal are benchmarked for
-// completeness.
-const enableComparativeBenchmarks = false
-
-func newBenchMount() *Mount {
- mount := &Mount{}
- mount.storeKey(&Mount{}, &Dentry{})
- return mount
-}
-
-func vdkey(mnt *Mount) VirtualDentry {
- parent, point := mnt.loadKey()
- return VirtualDentry{
- mount: parent,
- dentry: point,
- }
-}
-
-func BenchmarkMountTableParallelLookup(b *testing.B) {
- for numG, maxG := 1, runtime.GOMAXPROCS(0); numG >= 0 && numG <= maxG; numG *= 2 {
- for _, numMounts := range benchNumMounts {
- desc := fmt.Sprintf("%dx%d", numG, numMounts)
- b.Run(desc, func(b *testing.B) {
- var mt mountTable
- mt.Init()
- keys := make([]VirtualDentry, 0, numMounts)
- for i := 0; i < numMounts; i++ {
- mount := newBenchMount()
- mt.Insert(mount)
- keys = append(keys, vdkey(mount))
- }
-
- var ready sync.WaitGroup
- begin := make(chan struct{})
- var end sync.WaitGroup
- for g := 0; g < numG; g++ {
- ready.Add(1)
- end.Add(1)
- go func() {
- defer end.Done()
- ready.Done()
- <-begin
- for i := 0; i < b.N; i++ {
- k := keys[i&(numMounts-1)]
- m := mt.Lookup(k.mount, k.dentry)
- if m == nil {
- b.Fatalf("lookup failed")
- }
- if parent := m.parent(); parent != k.mount {
- b.Fatalf("lookup returned mount with parent %p, wanted %p", parent, k.mount)
- }
- if point := m.point(); point != k.dentry {
- b.Fatalf("lookup returned mount with point %p, wanted %p", point, k.dentry)
- }
- }
- }()
- }
-
- ready.Wait()
- b.ResetTimer()
- close(begin)
- end.Wait()
- })
- }
- }
-}
-
-func BenchmarkMountMapParallelLookup(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- for numG, maxG := 1, runtime.GOMAXPROCS(0); numG >= 0 && numG <= maxG; numG *= 2 {
- for _, numMounts := range benchNumMounts {
- desc := fmt.Sprintf("%dx%d", numG, numMounts)
- b.Run(desc, func(b *testing.B) {
- var mu sync.RWMutex
- ms := make(map[VirtualDentry]*Mount)
- keys := make([]VirtualDentry, 0, numMounts)
- for i := 0; i < numMounts; i++ {
- mount := newBenchMount()
- key := vdkey(mount)
- ms[key] = mount
- keys = append(keys, key)
- }
-
- var ready sync.WaitGroup
- begin := make(chan struct{})
- var end sync.WaitGroup
- for g := 0; g < numG; g++ {
- ready.Add(1)
- end.Add(1)
- go func() {
- defer end.Done()
- ready.Done()
- <-begin
- for i := 0; i < b.N; i++ {
- k := keys[i&(numMounts-1)]
- mu.RLock()
- m := ms[k]
- mu.RUnlock()
- if m == nil {
- b.Fatalf("lookup failed")
- }
- if parent := m.parent(); parent != k.mount {
- b.Fatalf("lookup returned mount with parent %p, wanted %p", parent, k.mount)
- }
- if point := m.point(); point != k.dentry {
- b.Fatalf("lookup returned mount with point %p, wanted %p", point, k.dentry)
- }
- }
- }()
- }
-
- ready.Wait()
- b.ResetTimer()
- close(begin)
- end.Wait()
- })
- }
- }
-}
-
-func BenchmarkMountSyncMapParallelLookup(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- for numG, maxG := 1, runtime.GOMAXPROCS(0); numG >= 0 && numG <= maxG; numG *= 2 {
- for _, numMounts := range benchNumMounts {
- desc := fmt.Sprintf("%dx%d", numG, numMounts)
- b.Run(desc, func(b *testing.B) {
- var ms sync.Map
- keys := make([]VirtualDentry, 0, numMounts)
- for i := 0; i < numMounts; i++ {
- mount := newBenchMount()
- key := vdkey(mount)
- ms.Store(key, mount)
- keys = append(keys, key)
- }
-
- var ready sync.WaitGroup
- begin := make(chan struct{})
- var end sync.WaitGroup
- for g := 0; g < numG; g++ {
- ready.Add(1)
- end.Add(1)
- go func() {
- defer end.Done()
- ready.Done()
- <-begin
- for i := 0; i < b.N; i++ {
- k := keys[i&(numMounts-1)]
- mi, ok := ms.Load(k)
- if !ok {
- b.Fatalf("lookup failed")
- }
- m := mi.(*Mount)
- if parent := m.parent(); parent != k.mount {
- b.Fatalf("lookup returned mount with parent %p, wanted %p", parent, k.mount)
- }
- if point := m.point(); point != k.dentry {
- b.Fatalf("lookup returned mount with point %p, wanted %p", point, k.dentry)
- }
- }
- }()
- }
-
- ready.Wait()
- b.ResetTimer()
- close(begin)
- end.Wait()
- })
- }
- }
-}
-
-func BenchmarkMountTableNegativeLookup(b *testing.B) {
- for _, numMounts := range benchNumMounts {
- desc := fmt.Sprintf("%d", numMounts)
- b.Run(desc, func(b *testing.B) {
- var mt mountTable
- mt.Init()
- for i := 0; i < numMounts; i++ {
- mt.Insert(newBenchMount())
- }
- negkeys := make([]VirtualDentry, 0, numMounts)
- for i := 0; i < numMounts; i++ {
- negkeys = append(negkeys, VirtualDentry{
- mount: &Mount{},
- dentry: &Dentry{},
- })
- }
-
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- k := negkeys[i&(numMounts-1)]
- m := mt.Lookup(k.mount, k.dentry)
- if m != nil {
- b.Fatalf("lookup got %p, wanted nil", m)
- }
- }
- })
- }
-}
-
-func BenchmarkMountMapNegativeLookup(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- for _, numMounts := range benchNumMounts {
- desc := fmt.Sprintf("%d", numMounts)
- b.Run(desc, func(b *testing.B) {
- var mu sync.RWMutex
- ms := make(map[VirtualDentry]*Mount)
- for i := 0; i < numMounts; i++ {
- mount := newBenchMount()
- ms[vdkey(mount)] = mount
- }
- negkeys := make([]VirtualDentry, 0, numMounts)
- for i := 0; i < numMounts; i++ {
- negkeys = append(negkeys, VirtualDentry{
- mount: &Mount{},
- dentry: &Dentry{},
- })
- }
-
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- k := negkeys[i&(numMounts-1)]
- mu.RLock()
- m := ms[k]
- mu.RUnlock()
- if m != nil {
- b.Fatalf("lookup got %p, wanted nil", m)
- }
- }
- })
- }
-}
-
-func BenchmarkMountSyncMapNegativeLookup(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- for _, numMounts := range benchNumMounts {
- desc := fmt.Sprintf("%d", numMounts)
- b.Run(desc, func(b *testing.B) {
- var ms sync.Map
- for i := 0; i < numMounts; i++ {
- mount := newBenchMount()
- ms.Store(vdkey(mount), mount)
- }
- negkeys := make([]VirtualDentry, 0, numMounts)
- for i := 0; i < numMounts; i++ {
- negkeys = append(negkeys, VirtualDentry{
- mount: &Mount{},
- dentry: &Dentry{},
- })
- }
-
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- k := negkeys[i&(numMounts-1)]
- m, _ := ms.Load(k)
- if m != nil {
- b.Fatalf("lookup got %p, wanted nil", m)
- }
- }
- })
- }
-}
-
-func BenchmarkMountTableInsert(b *testing.B) {
- // Preallocate Mounts so that allocation time isn't included in the
- // benchmark.
- mounts := make([]*Mount, 0, b.N)
- for i := 0; i < b.N; i++ {
- mounts = append(mounts, newBenchMount())
- }
-
- var mt mountTable
- mt.Init()
- b.ResetTimer()
- for i := range mounts {
- mt.Insert(mounts[i])
- }
-}
-
-func BenchmarkMountMapInsert(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- // Preallocate Mounts so that allocation time isn't included in the
- // benchmark.
- mounts := make([]*Mount, 0, b.N)
- for i := 0; i < b.N; i++ {
- mounts = append(mounts, newBenchMount())
- }
-
- ms := make(map[VirtualDentry]*Mount)
- b.ResetTimer()
- for i := range mounts {
- mount := mounts[i]
- ms[vdkey(mount)] = mount
- }
-}
-
-func BenchmarkMountSyncMapInsert(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- // Preallocate Mounts so that allocation time isn't included in the
- // benchmark.
- mounts := make([]*Mount, 0, b.N)
- for i := 0; i < b.N; i++ {
- mounts = append(mounts, newBenchMount())
- }
-
- var ms sync.Map
- b.ResetTimer()
- for i := range mounts {
- mount := mounts[i]
- ms.Store(vdkey(mount), mount)
- }
-}
-
-func BenchmarkMountTableRemove(b *testing.B) {
- mounts := make([]*Mount, 0, b.N)
- for i := 0; i < b.N; i++ {
- mounts = append(mounts, newBenchMount())
- }
- var mt mountTable
- mt.Init()
- for i := range mounts {
- mt.Insert(mounts[i])
- }
-
- b.ResetTimer()
- for i := range mounts {
- mt.Remove(mounts[i])
- }
-}
-
-func BenchmarkMountMapRemove(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- mounts := make([]*Mount, 0, b.N)
- for i := 0; i < b.N; i++ {
- mounts = append(mounts, newBenchMount())
- }
- ms := make(map[VirtualDentry]*Mount)
- for i := range mounts {
- mount := mounts[i]
- ms[vdkey(mount)] = mount
- }
-
- b.ResetTimer()
- for i := range mounts {
- mount := mounts[i]
- delete(ms, vdkey(mount))
- }
-}
-
-func BenchmarkMountSyncMapRemove(b *testing.B) {
- if !enableComparativeBenchmarks {
- b.Skipf("comparative benchmarks are disabled")
- }
-
- mounts := make([]*Mount, 0, b.N)
- for i := 0; i < b.N; i++ {
- mounts = append(mounts, newBenchMount())
- }
- var ms sync.Map
- for i := range mounts {
- mount := mounts[i]
- ms.Store(vdkey(mount), mount)
- }
-
- b.ResetTimer()
- for i := range mounts {
- mount := mounts[i]
- ms.Delete(vdkey(mount))
- }
-}