diff options
Diffstat (limited to 'pkg/sentry/vfs/mount_test.go')
-rw-r--r-- | pkg/sentry/vfs/mount_test.go | 465 |
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)) - } -} |