diff options
Diffstat (limited to 'pkg/sync')
-rw-r--r-- | pkg/sync/BUILD | 89 | ||||
-rw-r--r-- | pkg/sync/LICENSE | 27 | ||||
-rw-r--r-- | pkg/sync/README.md | 5 | ||||
-rw-r--r-- | pkg/sync/atomicptrmaptest/BUILD | 57 | ||||
-rw-r--r-- | pkg/sync/atomicptrmaptest/atomicptrmap.go | 20 | ||||
-rw-r--r-- | pkg/sync/atomicptrmaptest/atomicptrmap_test.go | 635 | ||||
-rw-r--r-- | pkg/sync/atomicptrtest/BUILD | 27 | ||||
-rw-r--r-- | pkg/sync/atomicptrtest/atomicptr_test.go | 31 | ||||
-rw-r--r-- | pkg/sync/gate_test.go | 129 | ||||
-rw-r--r-- | pkg/sync/generic_atomicptr_unsafe.go | 47 | ||||
-rw-r--r-- | pkg/sync/generic_atomicptrmap_unsafe.go | 500 | ||||
-rw-r--r-- | pkg/sync/generic_seqatomic_unsafe.go | 50 | ||||
-rw-r--r-- | pkg/sync/mutex_test.go | 71 | ||||
-rw-r--r-- | pkg/sync/rwmutex_test.go | 205 | ||||
-rw-r--r-- | pkg/sync/seqatomictest/BUILD | 32 | ||||
-rw-r--r-- | pkg/sync/seqatomictest/seqatomic_test.go | 132 | ||||
-rw-r--r-- | pkg/sync/seqcount_test.go | 100 |
17 files changed, 0 insertions, 2157 deletions
diff --git a/pkg/sync/BUILD b/pkg/sync/BUILD deleted file mode 100644 index 8b3a11c64..000000000 --- a/pkg/sync/BUILD +++ /dev/null @@ -1,89 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") -load("//tools/go_generics:defs.bzl", "go_template") - -package( - default_visibility = ["//:sandbox"], - licenses = ["notice"], -) - -exports_files(["LICENSE"]) - -go_template( - name = "generic_atomicptr", - srcs = ["generic_atomicptr_unsafe.go"], - types = [ - "Value", - ], -) - -go_template( - name = "generic_atomicptrmap", - srcs = ["generic_atomicptrmap_unsafe.go"], - opt_consts = [ - "ShardOrder", - ], - opt_types = [ - "Hasher", - ], - types = [ - "Key", - "Value", - ], - deps = [ - ":sync", - "//pkg/gohacks", - ], -) - -go_template( - name = "generic_seqatomic", - srcs = ["generic_seqatomic_unsafe.go"], - types = [ - "Value", - ], - deps = [ - ":sync", - "//pkg/gohacks", - ], -) - -go_library( - name = "sync", - srcs = [ - "aliases.go", - "checklocks_off_unsafe.go", - "checklocks_on_unsafe.go", - "gate_unsafe.go", - "goyield_go113_unsafe.go", - "goyield_unsafe.go", - "mutex_unsafe.go", - "nocopy.go", - "norace_unsafe.go", - "race_amd64.s", - "race_arm64.s", - "race_unsafe.go", - "runtime_unsafe.go", - "rwmutex_unsafe.go", - "seqcount.go", - "sync.go", - ], - marshal = False, - stateify = False, - visibility = ["//:sandbox"], - deps = [ - "//pkg/gohacks", - "//pkg/goid", - ], -) - -go_test( - name = "sync_test", - size = "small", - srcs = [ - "gate_test.go", - "mutex_test.go", - "rwmutex_test.go", - "seqcount_test.go", - ], - library = ":sync", -) diff --git a/pkg/sync/LICENSE b/pkg/sync/LICENSE deleted file mode 100644 index 6a66aea5e..000000000 --- a/pkg/sync/LICENSE +++ /dev/null @@ -1,27 +0,0 @@ -Copyright (c) 2009 The Go Authors. All rights reserved. - -Redistribution and use in source and binary forms, with or without -modification, are permitted provided that the following conditions are -met: - - * Redistributions of source code must retain the above copyright -notice, this list of conditions and the following disclaimer. - * Redistributions in binary form must reproduce the above -copyright notice, this list of conditions and the following disclaimer -in the documentation and/or other materials provided with the -distribution. - * Neither the name of Google Inc. nor the names of its -contributors may be used to endorse or promote products derived from -this software without specific prior written permission. - -THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/pkg/sync/README.md b/pkg/sync/README.md deleted file mode 100644 index 2183c4e20..000000000 --- a/pkg/sync/README.md +++ /dev/null @@ -1,5 +0,0 @@ -# Syncutil - -This package provides additional synchronization primitives not provided by the -Go stdlib 'sync' package. It is partially derived from the upstream 'sync' -package from go1.10. diff --git a/pkg/sync/atomicptrmaptest/BUILD b/pkg/sync/atomicptrmaptest/BUILD deleted file mode 100644 index 3f71ae97d..000000000 --- a/pkg/sync/atomicptrmaptest/BUILD +++ /dev/null @@ -1,57 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") -load("//tools/go_generics:defs.bzl", "go_template_instance") - -package( - default_visibility = ["//visibility:private"], - licenses = ["notice"], -) - -go_template_instance( - name = "test_atomicptrmap", - out = "test_atomicptrmap_unsafe.go", - package = "atomicptrmap", - prefix = "test", - template = "//pkg/sync:generic_atomicptrmap", - types = { - "Key": "int64", - "Value": "testValue", - }, -) - -go_template_instance( - name = "test_atomicptrmap_sharded", - out = "test_atomicptrmap_sharded_unsafe.go", - consts = { - "ShardOrder": "4", - }, - package = "atomicptrmap", - prefix = "test", - suffix = "Sharded", - template = "//pkg/sync:generic_atomicptrmap", - types = { - "Key": "int64", - "Value": "testValue", - }, -) - -go_library( - name = "atomicptrmap", - testonly = 1, - srcs = [ - "atomicptrmap.go", - "test_atomicptrmap_sharded_unsafe.go", - "test_atomicptrmap_unsafe.go", - ], - deps = [ - "//pkg/gohacks", - "//pkg/sync", - ], -) - -go_test( - name = "atomicptrmap_test", - size = "small", - srcs = ["atomicptrmap_test.go"], - library = ":atomicptrmap", - deps = ["//pkg/sync"], -) diff --git a/pkg/sync/atomicptrmaptest/atomicptrmap.go b/pkg/sync/atomicptrmaptest/atomicptrmap.go deleted file mode 100644 index 867821ce9..000000000 --- a/pkg/sync/atomicptrmaptest/atomicptrmap.go +++ /dev/null @@ -1,20 +0,0 @@ -// Copyright 2020 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 atomicptrmap instantiates generic_atomicptrmap for testing. -package atomicptrmap - -type testValue struct { - val int -} diff --git a/pkg/sync/atomicptrmaptest/atomicptrmap_test.go b/pkg/sync/atomicptrmaptest/atomicptrmap_test.go deleted file mode 100644 index 75a9997ef..000000000 --- a/pkg/sync/atomicptrmaptest/atomicptrmap_test.go +++ /dev/null @@ -1,635 +0,0 @@ -// Copyright 2020 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 atomicptrmap - -import ( - "context" - "fmt" - "math/rand" - "reflect" - "runtime" - "testing" - "time" - - "gvisor.dev/gvisor/pkg/sync" -) - -func TestConsistencyWithGoMap(t *testing.T) { - const maxKey = 16 - var vals [4]*testValue - for i := 1; /* leave vals[0] nil */ i < len(vals); i++ { - vals[i] = new(testValue) - } - var ( - m = make(map[int64]*testValue) - apm testAtomicPtrMap - ) - for i := 0; i < 100000; i++ { - // Apply a random operation to both m and apm and expect them to have - // the same result. Bias toward CompareAndSwap, which has the most - // cases; bias away from Range and RangeRepeatable, which are - // relatively expensive. - switch rand.Intn(10) { - case 0, 1: // Load - key := rand.Int63n(maxKey) - want := m[key] - got := apm.Load(key) - t.Logf("Load(%d) = %p", key, got) - if got != want { - t.Fatalf("got %p, wanted %p", got, want) - } - case 2, 3: // Swap - key := rand.Int63n(maxKey) - val := vals[rand.Intn(len(vals))] - want := m[key] - if val != nil { - m[key] = val - } else { - delete(m, key) - } - got := apm.Swap(key, val) - t.Logf("Swap(%d, %p) = %p", key, val, got) - if got != want { - t.Fatalf("got %p, wanted %p", got, want) - } - case 4, 5, 6, 7: // CompareAndSwap - key := rand.Int63n(maxKey) - oldVal := vals[rand.Intn(len(vals))] - newVal := vals[rand.Intn(len(vals))] - want := m[key] - if want == oldVal { - if newVal != nil { - m[key] = newVal - } else { - delete(m, key) - } - } - got := apm.CompareAndSwap(key, oldVal, newVal) - t.Logf("CompareAndSwap(%d, %p, %p) = %p", key, oldVal, newVal, got) - if got != want { - t.Fatalf("got %p, wanted %p", got, want) - } - case 8: // Range - got := make(map[int64]*testValue) - var ( - haveDup = false - dup int64 - ) - apm.Range(func(key int64, val *testValue) bool { - if _, ok := got[key]; ok && !haveDup { - haveDup = true - dup = key - } - got[key] = val - return true - }) - t.Logf("Range() = %v", got) - if !reflect.DeepEqual(got, m) { - t.Fatalf("got %v, wanted %v", got, m) - } - if haveDup { - t.Fatalf("got duplicate key %d", dup) - } - case 9: // RangeRepeatable - got := make(map[int64]*testValue) - apm.RangeRepeatable(func(key int64, val *testValue) bool { - got[key] = val - return true - }) - t.Logf("RangeRepeatable() = %v", got) - if !reflect.DeepEqual(got, m) { - t.Fatalf("got %v, wanted %v", got, m) - } - } - } -} - -func TestConcurrentHeterogeneous(t *testing.T) { - ctx, cancel := context.WithCancel(context.Background()) - var ( - apm testAtomicPtrMap - wg sync.WaitGroup - ) - defer func() { - cancel() - wg.Wait() - }() - - possibleKeyValuePairs := make(map[int64]map[*testValue]struct{}) - addKeyValuePair := func(key int64, val *testValue) { - values := possibleKeyValuePairs[key] - if values == nil { - values = make(map[*testValue]struct{}) - possibleKeyValuePairs[key] = values - } - values[val] = struct{}{} - } - - const numValuesPerKey = 4 - - // These goroutines use keys not used by any other goroutine. - const numPrivateKeys = 3 - for i := 0; i < numPrivateKeys; i++ { - key := int64(i) - var vals [numValuesPerKey]*testValue - for i := 1; /* leave vals[0] nil */ i < len(vals); i++ { - val := new(testValue) - vals[i] = val - addKeyValuePair(key, val) - } - wg.Add(1) - go func() { - defer wg.Done() - r := rand.New(rand.NewSource(rand.Int63())) - var stored *testValue - for ctx.Err() == nil { - switch r.Intn(4) { - case 0: - got := apm.Load(key) - if got != stored { - t.Errorf("Load(%d): got %p, wanted %p", key, got, stored) - return - } - case 1: - val := vals[r.Intn(len(vals))] - want := stored - stored = val - got := apm.Swap(key, val) - if got != want { - t.Errorf("Swap(%d, %p): got %p, wanted %p", key, val, got, want) - return - } - case 2, 3: - oldVal := vals[r.Intn(len(vals))] - newVal := vals[r.Intn(len(vals))] - want := stored - if stored == oldVal { - stored = newVal - } - got := apm.CompareAndSwap(key, oldVal, newVal) - if got != want { - t.Errorf("CompareAndSwap(%d, %p, %p): got %p, wanted %p", key, oldVal, newVal, got, want) - return - } - } - } - }() - } - - // These goroutines share a small set of keys. - const numSharedKeys = 2 - var ( - sharedKeys [numSharedKeys]int64 - sharedValues = make(map[int64][]*testValue) - sharedValuesSet = make(map[int64]map[*testValue]struct{}) - ) - for i := range sharedKeys { - key := int64(numPrivateKeys + i) - sharedKeys[i] = key - vals := make([]*testValue, numValuesPerKey) - valsSet := make(map[*testValue]struct{}) - for j := range vals { - val := new(testValue) - vals[j] = val - valsSet[val] = struct{}{} - addKeyValuePair(key, val) - } - sharedValues[key] = vals - sharedValuesSet[key] = valsSet - } - randSharedValue := func(r *rand.Rand, key int64) *testValue { - vals := sharedValues[key] - return vals[r.Intn(len(vals))] - } - for i := 0; i < 3; i++ { - wg.Add(1) - go func() { - defer wg.Done() - r := rand.New(rand.NewSource(rand.Int63())) - for ctx.Err() == nil { - keyIndex := r.Intn(len(sharedKeys)) - key := sharedKeys[keyIndex] - var ( - op string - got *testValue - ) - switch r.Intn(4) { - case 0: - op = "Load" - got = apm.Load(key) - case 1: - op = "Swap" - got = apm.Swap(key, randSharedValue(r, key)) - case 2, 3: - op = "CompareAndSwap" - got = apm.CompareAndSwap(key, randSharedValue(r, key), randSharedValue(r, key)) - } - if got != nil { - valsSet := sharedValuesSet[key] - if _, ok := valsSet[got]; !ok { - t.Errorf("%s: got key %d, value %p; expected value in %v", op, key, got, valsSet) - return - } - } - } - }() - } - - // This goroutine repeatedly searches for unused keys. - wg.Add(1) - go func() { - defer wg.Done() - r := rand.New(rand.NewSource(rand.Int63())) - for ctx.Err() == nil { - key := -1 - r.Int63() - if got := apm.Load(key); got != nil { - t.Errorf("Load(%d): got %p, wanted nil", key, got) - } - } - }() - - // This goroutine repeatedly calls RangeRepeatable() and checks that each - // key corresponds to an expected value. - wg.Add(1) - go func() { - defer wg.Done() - abort := false - for !abort && ctx.Err() == nil { - apm.RangeRepeatable(func(key int64, val *testValue) bool { - values, ok := possibleKeyValuePairs[key] - if !ok { - t.Errorf("RangeRepeatable: got invalid key %d", key) - abort = true - return false - } - if _, ok := values[val]; !ok { - t.Errorf("RangeRepeatable: got key %d, value %p; expected one of %v", key, val, values) - abort = true - return false - } - return true - }) - } - }() - - // Finally, the main goroutine spins for the length of the test calling - // Range() and checking that each key that it observes is unique and - // corresponds to an expected value. - seenKeys := make(map[int64]struct{}) - const testDuration = 5 * time.Second - end := time.Now().Add(testDuration) - abort := false - for time.Now().Before(end) { - apm.Range(func(key int64, val *testValue) bool { - values, ok := possibleKeyValuePairs[key] - if !ok { - t.Errorf("Range: got invalid key %d", key) - abort = true - return false - } - if _, ok := values[val]; !ok { - t.Errorf("Range: got key %d, value %p; expected one of %v", key, val, values) - abort = true - return false - } - if _, ok := seenKeys[key]; ok { - t.Errorf("Range: got duplicate key %d", key) - abort = true - return false - } - seenKeys[key] = struct{}{} - return true - }) - if abort { - break - } - for k := range seenKeys { - delete(seenKeys, k) - } - } -} - -type benchmarkableMap interface { - Load(key int64) *testValue - Store(key int64, val *testValue) - LoadOrStore(key int64, val *testValue) (*testValue, bool) - Delete(key int64) -} - -// rwMutexMap implements benchmarkableMap for a RWMutex-protected Go map. -type rwMutexMap struct { - mu sync.RWMutex - m map[int64]*testValue -} - -func (m *rwMutexMap) Load(key int64) *testValue { - m.mu.RLock() - defer m.mu.RUnlock() - return m.m[key] -} - -func (m *rwMutexMap) Store(key int64, val *testValue) { - m.mu.Lock() - defer m.mu.Unlock() - if m.m == nil { - m.m = make(map[int64]*testValue) - } - m.m[key] = val -} - -func (m *rwMutexMap) LoadOrStore(key int64, val *testValue) (*testValue, bool) { - m.mu.Lock() - defer m.mu.Unlock() - if m.m == nil { - m.m = make(map[int64]*testValue) - } - if oldVal, ok := m.m[key]; ok { - return oldVal, true - } - m.m[key] = val - return val, false -} - -func (m *rwMutexMap) Delete(key int64) { - m.mu.Lock() - defer m.mu.Unlock() - delete(m.m, key) -} - -// syncMap implements benchmarkableMap for a sync.Map. -type syncMap struct { - m sync.Map -} - -func (m *syncMap) Load(key int64) *testValue { - val, ok := m.m.Load(key) - if !ok { - return nil - } - return val.(*testValue) -} - -func (m *syncMap) Store(key int64, val *testValue) { - m.m.Store(key, val) -} - -func (m *syncMap) LoadOrStore(key int64, val *testValue) (*testValue, bool) { - actual, loaded := m.m.LoadOrStore(key, val) - return actual.(*testValue), loaded -} - -func (m *syncMap) Delete(key int64) { - m.m.Delete(key) -} - -// benchmarkableAtomicPtrMap implements benchmarkableMap for testAtomicPtrMap. -type benchmarkableAtomicPtrMap struct { - m testAtomicPtrMap -} - -func (m *benchmarkableAtomicPtrMap) Load(key int64) *testValue { - return m.m.Load(key) -} - -func (m *benchmarkableAtomicPtrMap) Store(key int64, val *testValue) { - m.m.Store(key, val) -} - -func (m *benchmarkableAtomicPtrMap) LoadOrStore(key int64, val *testValue) (*testValue, bool) { - if prev := m.m.CompareAndSwap(key, nil, val); prev != nil { - return prev, true - } - return val, false -} - -func (m *benchmarkableAtomicPtrMap) Delete(key int64) { - m.m.Store(key, nil) -} - -// benchmarkableAtomicPtrMapSharded implements benchmarkableMap for testAtomicPtrMapSharded. -type benchmarkableAtomicPtrMapSharded struct { - m testAtomicPtrMapSharded -} - -func (m *benchmarkableAtomicPtrMapSharded) Load(key int64) *testValue { - return m.m.Load(key) -} - -func (m *benchmarkableAtomicPtrMapSharded) Store(key int64, val *testValue) { - m.m.Store(key, val) -} - -func (m *benchmarkableAtomicPtrMapSharded) LoadOrStore(key int64, val *testValue) (*testValue, bool) { - if prev := m.m.CompareAndSwap(key, nil, val); prev != nil { - return prev, true - } - return val, false -} - -func (m *benchmarkableAtomicPtrMapSharded) Delete(key int64) { - m.m.Store(key, nil) -} - -var mapImpls = [...]struct { - name string - ctor func() benchmarkableMap -}{ - { - name: "RWMutexMap", - ctor: func() benchmarkableMap { - return new(rwMutexMap) - }, - }, - { - name: "SyncMap", - ctor: func() benchmarkableMap { - return new(syncMap) - }, - }, - { - name: "AtomicPtrMap", - ctor: func() benchmarkableMap { - return new(benchmarkableAtomicPtrMap) - }, - }, - { - name: "AtomicPtrMapSharded", - ctor: func() benchmarkableMap { - return new(benchmarkableAtomicPtrMapSharded) - }, - }, -} - -func benchmarkStoreDelete(b *testing.B, mapCtor func() benchmarkableMap) { - m := mapCtor() - val := &testValue{} - for i := 0; i < b.N; i++ { - m.Store(int64(i), val) - } - for i := 0; i < b.N; i++ { - m.Delete(int64(i)) - } -} - -func BenchmarkStoreDelete(b *testing.B) { - for _, mapImpl := range mapImpls { - b.Run(mapImpl.name, func(b *testing.B) { - benchmarkStoreDelete(b, mapImpl.ctor) - }) - } -} - -func benchmarkLoadOrStoreDelete(b *testing.B, mapCtor func() benchmarkableMap) { - m := mapCtor() - val := &testValue{} - for i := 0; i < b.N; i++ { - m.LoadOrStore(int64(i), val) - } - for i := 0; i < b.N; i++ { - m.Delete(int64(i)) - } -} - -func BenchmarkLoadOrStoreDelete(b *testing.B) { - for _, mapImpl := range mapImpls { - b.Run(mapImpl.name, func(b *testing.B) { - benchmarkLoadOrStoreDelete(b, mapImpl.ctor) - }) - } -} - -func benchmarkLookupPositive(b *testing.B, mapCtor func() benchmarkableMap) { - m := mapCtor() - val := &testValue{} - for i := 0; i < b.N; i++ { - m.Store(int64(i), val) - } - b.ResetTimer() - for i := 0; i < b.N; i++ { - m.Load(int64(i)) - } -} - -func BenchmarkLookupPositive(b *testing.B) { - for _, mapImpl := range mapImpls { - b.Run(mapImpl.name, func(b *testing.B) { - benchmarkLookupPositive(b, mapImpl.ctor) - }) - } -} - -func benchmarkLookupNegative(b *testing.B, mapCtor func() benchmarkableMap) { - m := mapCtor() - val := &testValue{} - for i := 0; i < b.N; i++ { - m.Store(int64(i), val) - } - b.ResetTimer() - for i := 0; i < b.N; i++ { - m.Load(int64(-1 - i)) - } -} - -func BenchmarkLookupNegative(b *testing.B) { - for _, mapImpl := range mapImpls { - b.Run(mapImpl.name, func(b *testing.B) { - benchmarkLookupNegative(b, mapImpl.ctor) - }) - } -} - -type benchmarkConcurrentOptions struct { - // loadsPerMutationPair is the number of map lookups between each - // insertion/deletion pair. - loadsPerMutationPair int - - // If changeKeys is true, the keys used by each goroutine change between - // iterations of the test. - changeKeys bool -} - -func benchmarkConcurrent(b *testing.B, mapCtor func() benchmarkableMap, opts benchmarkConcurrentOptions) { - var ( - started sync.WaitGroup - workers sync.WaitGroup - ) - started.Add(1) - - m := mapCtor() - val := &testValue{} - // Insert a large number of unused elements into the map so that used - // elements are distributed throughout memory. - for i := 0; i < 10000; i++ { - m.Store(int64(-1-i), val) - } - // n := ceil(b.N / (opts.loadsPerMutationPair + 2)) - n := (b.N + opts.loadsPerMutationPair + 1) / (opts.loadsPerMutationPair + 2) - for i, procs := 0, runtime.GOMAXPROCS(0); i < procs; i++ { - workerID := i - workers.Add(1) - go func() { - defer workers.Done() - started.Wait() - for i := 0; i < n; i++ { - var key int64 - if opts.changeKeys { - key = int64(workerID*n + i) - } else { - key = int64(workerID) - } - m.LoadOrStore(key, val) - for j := 0; j < opts.loadsPerMutationPair; j++ { - m.Load(key) - } - m.Delete(key) - } - }() - } - - b.ResetTimer() - started.Done() - workers.Wait() -} - -func BenchmarkConcurrent(b *testing.B) { - changeKeysChoices := [...]struct { - name string - val bool - }{ - {"FixedKeys", false}, - {"ChangingKeys", true}, - } - writePcts := [...]struct { - name string - loadsPerMutationPair int - }{ - {"1PercentWrites", 198}, - {"10PercentWrites", 18}, - {"50PercentWrites", 2}, - } - for _, changeKeys := range changeKeysChoices { - for _, writePct := range writePcts { - for _, mapImpl := range mapImpls { - name := fmt.Sprintf("%s_%s_%s", changeKeys.name, writePct.name, mapImpl.name) - b.Run(name, func(b *testing.B) { - benchmarkConcurrent(b, mapImpl.ctor, benchmarkConcurrentOptions{ - loadsPerMutationPair: writePct.loadsPerMutationPair, - changeKeys: changeKeys.val, - }) - }) - } - } - } -} diff --git a/pkg/sync/atomicptrtest/BUILD b/pkg/sync/atomicptrtest/BUILD deleted file mode 100644 index e97553254..000000000 --- a/pkg/sync/atomicptrtest/BUILD +++ /dev/null @@ -1,27 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") -load("//tools/go_generics:defs.bzl", "go_template_instance") - -package(licenses = ["notice"]) - -go_template_instance( - name = "atomicptr_int", - out = "atomicptr_int_unsafe.go", - package = "atomicptr", - suffix = "Int", - template = "//pkg/sync:generic_atomicptr", - types = { - "Value": "int", - }, -) - -go_library( - name = "atomicptr", - srcs = ["atomicptr_int_unsafe.go"], -) - -go_test( - name = "atomicptr_test", - size = "small", - srcs = ["atomicptr_test.go"], - library = ":atomicptr", -) diff --git a/pkg/sync/atomicptrtest/atomicptr_test.go b/pkg/sync/atomicptrtest/atomicptr_test.go deleted file mode 100644 index 8fdc5112e..000000000 --- a/pkg/sync/atomicptrtest/atomicptr_test.go +++ /dev/null @@ -1,31 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package atomicptr - -import ( - "testing" -) - -func newInt(val int) *int { - return &val -} - -func TestAtomicPtr(t *testing.T) { - var p AtomicPtrInt - if got := p.Load(); got != nil { - t.Errorf("initial value is %p (%v), wanted nil", got, got) - } - want := newInt(42) - p.Store(want) - if got := p.Load(); got != want { - t.Errorf("wrong value: got %p (%v), wanted %p (%v)", got, got, want, want) - } - want = newInt(100) - p.Store(want) - if got := p.Load(); got != want { - t.Errorf("wrong value: got %p (%v), wanted %p (%v)", got, got, want, want) - } -} diff --git a/pkg/sync/gate_test.go b/pkg/sync/gate_test.go deleted file mode 100644 index 82ce02b97..000000000 --- a/pkg/sync/gate_test.go +++ /dev/null @@ -1,129 +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 sync - -import ( - "context" - "runtime" - "sync/atomic" - "testing" - "time" -) - -func TestGateBasic(t *testing.T) { - var g Gate - - if !g.Enter() { - t.Fatalf("Enter failed before Close") - } - g.Leave() - - g.Close() - if g.Enter() { - t.Fatalf("Enter succeeded after Close") - } -} - -func TestGateConcurrent(t *testing.T) { - // Each call to testGateConcurrentOnce tests behavior around a single call - // to Gate.Close, so run many short tests to increase the probability of - // flushing out any issues. - totalTime := 5 * time.Second - timePerTest := 20 * time.Millisecond - numTests := int(totalTime / timePerTest) - for i := 0; i < numTests; i++ { - testGateConcurrentOnce(t, timePerTest) - } -} - -func testGateConcurrentOnce(t *testing.T, d time.Duration) { - const numGoroutines = 1000 - - ctx, cancel := context.WithCancel(context.Background()) - var wg WaitGroup - defer func() { - cancel() - wg.Wait() - }() - - var g Gate - closeState := int32(0) // set to 1 before g.Close() and 2 after it returns - - // Start a large number of goroutines that repeatedly attempt to enter the - // gate and get the expected result. - for i := 0; i < numGoroutines; i++ { - wg.Add(1) - go func() { - defer wg.Done() - for ctx.Err() == nil { - closedBeforeEnter := atomic.LoadInt32(&closeState) == 2 - if g.Enter() { - closedBeforeLeave := atomic.LoadInt32(&closeState) == 2 - g.Leave() - if closedBeforeEnter { - t.Errorf("Enter succeeded after Close") - return - } - if closedBeforeLeave { - t.Errorf("Close returned before Leave") - return - } - } else { - if atomic.LoadInt32(&closeState) == 0 { - t.Errorf("Enter failed before Close") - return - } - } - // Go does not preempt busy loops until Go 1.14. - runtime.Gosched() - } - }() - } - - // Allow goroutines to enter the gate successfully for half of the test's - // duration, then close the gate and allow goroutines to fail to enter the - // gate for the remaining half. - time.Sleep(d / 2) - atomic.StoreInt32(&closeState, 1) - g.Close() - atomic.StoreInt32(&closeState, 2) - time.Sleep(d / 2) -} - -func BenchmarkGateEnterLeave(b *testing.B) { - var g Gate - for i := 0; i < b.N; i++ { - g.Enter() - g.Leave() - } -} - -func BenchmarkGateClose(b *testing.B) { - for i := 0; i < b.N; i++ { - var g Gate - g.Close() - } -} - -func BenchmarkGateEnterLeaveAsyncClose(b *testing.B) { - for i := 0; i < b.N; i++ { - var g Gate - g.Enter() - go func() { - g.Leave() - }() - g.Close() - } -} diff --git a/pkg/sync/generic_atomicptr_unsafe.go b/pkg/sync/generic_atomicptr_unsafe.go deleted file mode 100644 index 82b6df18c..000000000 --- a/pkg/sync/generic_atomicptr_unsafe.go +++ /dev/null @@ -1,47 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// Package seqatomic doesn't exist. This file must be instantiated using the -// go_template_instance rule in tools/go_generics/defs.bzl. -package seqatomic - -import ( - "sync/atomic" - "unsafe" -) - -// Value is a required type parameter. -type Value struct{} - -// An AtomicPtr is a pointer to a value of type Value that can be atomically -// loaded and stored. The zero value of an AtomicPtr represents nil. -// -// Note that copying AtomicPtr by value performs a non-atomic read of the -// stored pointer, which is unsafe if Store() can be called concurrently; in -// this case, do `dst.Store(src.Load())` instead. -// -// +stateify savable -type AtomicPtr struct { - ptr unsafe.Pointer `state:".(*Value)"` -} - -func (p *AtomicPtr) savePtr() *Value { - return p.Load() -} - -func (p *AtomicPtr) loadPtr(v *Value) { - p.Store(v) -} - -// Load returns the value set by the most recent Store. It returns nil if there -// has been no previous call to Store. -func (p *AtomicPtr) Load() *Value { - return (*Value)(atomic.LoadPointer(&p.ptr)) -} - -// Store sets the value returned by Load to x. -func (p *AtomicPtr) Store(x *Value) { - atomic.StorePointer(&p.ptr, (unsafe.Pointer)(x)) -} diff --git a/pkg/sync/generic_atomicptrmap_unsafe.go b/pkg/sync/generic_atomicptrmap_unsafe.go deleted file mode 100644 index 3e98cb309..000000000 --- a/pkg/sync/generic_atomicptrmap_unsafe.go +++ /dev/null @@ -1,500 +0,0 @@ -// Copyright 2020 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 atomicptrmap doesn't exist. This file must be instantiated using the -// go_template_instance rule in tools/go_generics/defs.bzl. -package atomicptrmap - -import ( - "sync/atomic" - "unsafe" - - "gvisor.dev/gvisor/pkg/gohacks" - "gvisor.dev/gvisor/pkg/sync" -) - -// Key is a required type parameter. -type Key struct{} - -// Value is a required type parameter. -type Value struct{} - -const ( - // ShardOrder is an optional parameter specifying the base-2 log of the - // number of shards per AtomicPtrMap. Higher values of ShardOrder reduce - // unnecessary synchronization between unrelated concurrent operations, - // improving performance for write-heavy workloads, but increase memory - // usage for small maps. - ShardOrder = 0 -) - -// Hasher is an optional type parameter. If Hasher is provided, it must define -// the Init and Hash methods. One Hasher will be shared by all AtomicPtrMaps. -type Hasher struct { - defaultHasher -} - -// defaultHasher is the default Hasher. This indirection exists because -// defaultHasher must exist even if a custom Hasher is provided, to prevent the -// Go compiler from complaining about defaultHasher's unused imports. -type defaultHasher struct { - fn func(unsafe.Pointer, uintptr) uintptr - seed uintptr -} - -// Init initializes the Hasher. -func (h *defaultHasher) Init() { - h.fn = sync.MapKeyHasher(map[Key]*Value(nil)) - h.seed = sync.RandUintptr() -} - -// Hash returns the hash value for the given Key. -func (h *defaultHasher) Hash(key Key) uintptr { - return h.fn(gohacks.Noescape(unsafe.Pointer(&key)), h.seed) -} - -var hasher Hasher - -func init() { - hasher.Init() -} - -// An AtomicPtrMap maps Keys to non-nil pointers to Values. AtomicPtrMap are -// safe for concurrent use from multiple goroutines without additional -// synchronization. -// -// The zero value of AtomicPtrMap is empty (maps all Keys to nil) and ready for -// use. AtomicPtrMaps must not be copied after first use. -// -// sync.Map may be faster than AtomicPtrMap if most operations on the map are -// concurrent writes to a fixed set of keys. AtomicPtrMap is usually faster in -// other circumstances. -type AtomicPtrMap struct { - // AtomicPtrMap is implemented as a hash table with the following - // properties: - // - // * Collisions are resolved with quadratic probing. Of the two major - // alternatives, Robin Hood linear probing makes it difficult for writers - // to execute in parallel, and bucketing is less effective in Go due to - // lack of SIMD. - // - // * The table is optionally divided into shards indexed by hash to further - // reduce unnecessary synchronization. - - shards [1 << ShardOrder]apmShard -} - -func (m *AtomicPtrMap) shard(hash uintptr) *apmShard { - // Go defines right shifts >= width of shifted unsigned operand as 0, so - // this is correct even if ShardOrder is 0 (although nogo complains because - // nogo is dumb). - const indexLSB = unsafe.Sizeof(uintptr(0))*8 - ShardOrder - index := hash >> indexLSB - return (*apmShard)(unsafe.Pointer(uintptr(unsafe.Pointer(&m.shards)) + (index * unsafe.Sizeof(apmShard{})))) -} - -type apmShard struct { - apmShardMutationData - _ [apmShardMutationDataPadding]byte - apmShardLookupData - _ [apmShardLookupDataPadding]byte -} - -type apmShardMutationData struct { - dirtyMu sync.Mutex // serializes slot transitions out of empty - dirty uintptr // # slots with val != nil - count uintptr // # slots with val != nil and val != tombstone() - rehashMu sync.Mutex // serializes rehashing -} - -type apmShardLookupData struct { - seq sync.SeqCount // allows atomic reads of slots+mask - slots unsafe.Pointer // [mask+1]slot or nil; protected by rehashMu/seq - mask uintptr // always (a power of 2) - 1; protected by rehashMu/seq -} - -const ( - cacheLineBytes = 64 - // Cache line padding is enabled if sharding is. - apmEnablePadding = (ShardOrder + 63) >> 6 // 0 if ShardOrder == 0, 1 otherwise - // The -1 and +1 below are required to ensure that if unsafe.Sizeof(T) % - // cacheLineBytes == 0, then padding is 0 (rather than cacheLineBytes). - apmShardMutationDataRequiredPadding = cacheLineBytes - (((unsafe.Sizeof(apmShardMutationData{}) - 1) % cacheLineBytes) + 1) - apmShardMutationDataPadding = apmEnablePadding * apmShardMutationDataRequiredPadding - apmShardLookupDataRequiredPadding = cacheLineBytes - (((unsafe.Sizeof(apmShardLookupData{}) - 1) % cacheLineBytes) + 1) - apmShardLookupDataPadding = apmEnablePadding * apmShardLookupDataRequiredPadding - - // These define fractional thresholds for when apmShard.rehash() is called - // (i.e. the load factor) and when it rehases to a larger table - // respectively. They are chosen such that the rehash threshold = the - // expansion threshold + 1/2, so that when reuse of deleted slots is rare - // or non-existent, rehashing occurs after the insertion of at least 1/2 - // the table's size in new entries, which is acceptably infrequent. - apmRehashThresholdNum = 2 - apmRehashThresholdDen = 3 - apmExpansionThresholdNum = 1 - apmExpansionThresholdDen = 6 -) - -type apmSlot struct { - // slot states are indicated by val: - // - // * Empty: val == nil; key is meaningless. May transition to full or - // evacuated with dirtyMu locked. - // - // * Full: val != nil, tombstone(), or evacuated(); key is immutable. val - // is the Value mapped to key. May transition to deleted or evacuated. - // - // * Deleted: val == tombstone(); key is still immutable. key is mapped to - // no Value. May transition to full or evacuated. - // - // * Evacuated: val == evacuated(); key is immutable. Set by rehashing on - // slots that have already been moved, requiring readers to wait for - // rehashing to complete and use the new table. Terminal state. - // - // Note that once val is non-nil, it cannot become nil again. That is, the - // transition from empty to non-empty is irreversible for a given slot; - // the only way to create more empty slots is by rehashing. - val unsafe.Pointer - key Key -} - -func apmSlotAt(slots unsafe.Pointer, pos uintptr) *apmSlot { - return (*apmSlot)(unsafe.Pointer(uintptr(slots) + pos*unsafe.Sizeof(apmSlot{}))) -} - -var tombstoneObj byte - -func tombstone() unsafe.Pointer { - return unsafe.Pointer(&tombstoneObj) -} - -var evacuatedObj byte - -func evacuated() unsafe.Pointer { - return unsafe.Pointer(&evacuatedObj) -} - -// Load returns the Value stored in m for key. -func (m *AtomicPtrMap) Load(key Key) *Value { - hash := hasher.Hash(key) - shard := m.shard(hash) - -retry: - epoch := shard.seq.BeginRead() - slots := atomic.LoadPointer(&shard.slots) - mask := atomic.LoadUintptr(&shard.mask) - if !shard.seq.ReadOk(epoch) { - goto retry - } - if slots == nil { - return nil - } - - i := hash & mask - inc := uintptr(1) - for { - slot := apmSlotAt(slots, i) - slotVal := atomic.LoadPointer(&slot.val) - if slotVal == nil { - // Empty slot; end of probe sequence. - return nil - } - if slotVal == evacuated() { - // Racing with rehashing. - goto retry - } - if slot.key == key { - if slotVal == tombstone() { - return nil - } - return (*Value)(slotVal) - } - i = (i + inc) & mask - inc++ - } -} - -// Store stores the Value val for key. -func (m *AtomicPtrMap) Store(key Key, val *Value) { - m.maybeCompareAndSwap(key, false, nil, val) -} - -// Swap stores the Value val for key and returns the previously-mapped Value. -func (m *AtomicPtrMap) Swap(key Key, val *Value) *Value { - return m.maybeCompareAndSwap(key, false, nil, val) -} - -// CompareAndSwap checks that the Value stored for key is oldVal; if it is, it -// stores the Value newVal for key. CompareAndSwap returns the previous Value -// stored for key, whether or not it stores newVal. -func (m *AtomicPtrMap) CompareAndSwap(key Key, oldVal, newVal *Value) *Value { - return m.maybeCompareAndSwap(key, true, oldVal, newVal) -} - -func (m *AtomicPtrMap) maybeCompareAndSwap(key Key, compare bool, typedOldVal, typedNewVal *Value) *Value { - hash := hasher.Hash(key) - shard := m.shard(hash) - oldVal := tombstone() - if typedOldVal != nil { - oldVal = unsafe.Pointer(typedOldVal) - } - newVal := tombstone() - if typedNewVal != nil { - newVal = unsafe.Pointer(typedNewVal) - } - -retry: - epoch := shard.seq.BeginRead() - slots := atomic.LoadPointer(&shard.slots) - mask := atomic.LoadUintptr(&shard.mask) - if !shard.seq.ReadOk(epoch) { - goto retry - } - if slots == nil { - if (compare && oldVal != tombstone()) || newVal == tombstone() { - return nil - } - // Need to allocate a table before insertion. - shard.rehash(nil) - goto retry - } - - i := hash & mask - inc := uintptr(1) - for { - slot := apmSlotAt(slots, i) - slotVal := atomic.LoadPointer(&slot.val) - if slotVal == nil { - if (compare && oldVal != tombstone()) || newVal == tombstone() { - return nil - } - // Try to grab this slot for ourselves. - shard.dirtyMu.Lock() - slotVal = atomic.LoadPointer(&slot.val) - if slotVal == nil { - // Check if we need to rehash before dirtying a slot. - if dirty, capacity := shard.dirty+1, mask+1; dirty*apmRehashThresholdDen >= capacity*apmRehashThresholdNum { - shard.dirtyMu.Unlock() - shard.rehash(slots) - goto retry - } - slot.key = key - atomic.StorePointer(&slot.val, newVal) // transitions slot to full - shard.dirty++ - atomic.AddUintptr(&shard.count, 1) - shard.dirtyMu.Unlock() - return nil - } - // Raced with another store; the slot is no longer empty. Continue - // with the new value of slotVal since we may have raced with - // another store of key. - shard.dirtyMu.Unlock() - } - if slotVal == evacuated() { - // Racing with rehashing. - goto retry - } - if slot.key == key { - // We're reusing an existing slot, so rehashing isn't necessary. - for { - if (compare && oldVal != slotVal) || newVal == slotVal { - if slotVal == tombstone() { - return nil - } - return (*Value)(slotVal) - } - if atomic.CompareAndSwapPointer(&slot.val, slotVal, newVal) { - if slotVal == tombstone() { - atomic.AddUintptr(&shard.count, 1) - return nil - } - if newVal == tombstone() { - atomic.AddUintptr(&shard.count, ^uintptr(0) /* -1 */) - } - return (*Value)(slotVal) - } - slotVal = atomic.LoadPointer(&slot.val) - if slotVal == evacuated() { - goto retry - } - } - } - // This produces a triangular number sequence of offsets from the - // initially-probed position. - i = (i + inc) & mask - inc++ - } -} - -// rehash is marked nosplit to avoid preemption during table copying. -//go:nosplit -func (shard *apmShard) rehash(oldSlots unsafe.Pointer) { - shard.rehashMu.Lock() - defer shard.rehashMu.Unlock() - - if shard.slots != oldSlots { - // Raced with another call to rehash(). - return - } - - // Determine the size of the new table. Constraints: - // - // * The size of the table must be a power of two to ensure that every slot - // is visitable by every probe sequence under quadratic probing with - // triangular numbers. - // - // * The size of the table cannot decrease because even if shard.count is - // currently smaller than shard.dirty, concurrent stores that reuse - // existing slots can drive shard.count back up to a maximum of - // shard.dirty. - newSize := uintptr(8) // arbitrary initial size - if oldSlots != nil { - oldSize := shard.mask + 1 - newSize = oldSize - if count := atomic.LoadUintptr(&shard.count) + 1; count*apmExpansionThresholdDen > oldSize*apmExpansionThresholdNum { - newSize *= 2 - } - } - - // Allocate the new table. - newSlotsSlice := make([]apmSlot, newSize) - newSlotsHeader := (*gohacks.SliceHeader)(unsafe.Pointer(&newSlotsSlice)) - newSlots := newSlotsHeader.Data - newMask := newSize - 1 - - // Start a writer critical section now so that racing users of the old - // table that observe evacuated() wait for the new table. (But lock dirtyMu - // first since doing so may block, which we don't want to do during the - // writer critical section.) - shard.dirtyMu.Lock() - shard.seq.BeginWrite() - - if oldSlots != nil { - realCount := uintptr(0) - // Copy old entries to the new table. - oldMask := shard.mask - for i := uintptr(0); i <= oldMask; i++ { - oldSlot := apmSlotAt(oldSlots, i) - val := atomic.SwapPointer(&oldSlot.val, evacuated()) - if val == nil || val == tombstone() { - continue - } - hash := hasher.Hash(oldSlot.key) - j := hash & newMask - inc := uintptr(1) - for { - newSlot := apmSlotAt(newSlots, j) - if newSlot.val == nil { - newSlot.val = val - newSlot.key = oldSlot.key - break - } - j = (j + inc) & newMask - inc++ - } - realCount++ - } - // Update dirty to reflect that tombstones were not copied to the new - // table. Use realCount since a concurrent mutator may not have updated - // shard.count yet. - shard.dirty = realCount - } - - // Switch to the new table. - atomic.StorePointer(&shard.slots, newSlots) - atomic.StoreUintptr(&shard.mask, newMask) - - shard.seq.EndWrite() - shard.dirtyMu.Unlock() -} - -// Range invokes f on each Key-Value pair stored in m. If any call to f returns -// false, Range stops iteration and returns. -// -// Range does not necessarily correspond to any consistent snapshot of the -// Map's contents: no Key will be visited more than once, but if the Value for -// any Key is stored or deleted concurrently, Range may reflect any mapping for -// that Key from any point during the Range call. -// -// f must not call other methods on m. -func (m *AtomicPtrMap) Range(f func(key Key, val *Value) bool) { - for si := 0; si < len(m.shards); si++ { - shard := &m.shards[si] - if !shard.doRange(f) { - return - } - } -} - -func (shard *apmShard) doRange(f func(key Key, val *Value) bool) bool { - // We have to lock rehashMu because if we handled races with rehashing by - // retrying, f could see the same key twice. - shard.rehashMu.Lock() - defer shard.rehashMu.Unlock() - slots := shard.slots - if slots == nil { - return true - } - mask := shard.mask - for i := uintptr(0); i <= mask; i++ { - slot := apmSlotAt(slots, i) - slotVal := atomic.LoadPointer(&slot.val) - if slotVal == nil || slotVal == tombstone() { - continue - } - if !f(slot.key, (*Value)(slotVal)) { - return false - } - } - return true -} - -// RangeRepeatable is like Range, but: -// -// * RangeRepeatable may visit the same Key multiple times in the presence of -// concurrent mutators, possibly passing different Values to f in different -// calls. -// -// * It is safe for f to call other methods on m. -func (m *AtomicPtrMap) RangeRepeatable(f func(key Key, val *Value) bool) { - for si := 0; si < len(m.shards); si++ { - shard := &m.shards[si] - - retry: - epoch := shard.seq.BeginRead() - slots := atomic.LoadPointer(&shard.slots) - mask := atomic.LoadUintptr(&shard.mask) - if !shard.seq.ReadOk(epoch) { - goto retry - } - if slots == nil { - continue - } - - for i := uintptr(0); i <= mask; i++ { - slot := apmSlotAt(slots, i) - slotVal := atomic.LoadPointer(&slot.val) - if slotVal == evacuated() { - goto retry - } - if slotVal == nil || slotVal == tombstone() { - continue - } - if !f(slot.key, (*Value)(slotVal)) { - return - } - } - } -} diff --git a/pkg/sync/generic_seqatomic_unsafe.go b/pkg/sync/generic_seqatomic_unsafe.go deleted file mode 100644 index 9578c9c52..000000000 --- a/pkg/sync/generic_seqatomic_unsafe.go +++ /dev/null @@ -1,50 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// Package seqatomic doesn't exist. This file must be instantiated using the -// go_template_instance rule in tools/go_generics/defs.bzl. -package seqatomic - -import ( - "unsafe" - - "gvisor.dev/gvisor/pkg/gohacks" - "gvisor.dev/gvisor/pkg/sync" -) - -// Value is a required type parameter. -type Value struct{} - -// SeqAtomicLoad returns a copy of *ptr, ensuring that the read does not race -// with any writer critical sections in seq. -// -//go:nosplit -func SeqAtomicLoad(seq *sync.SeqCount, ptr *Value) Value { - for { - if val, ok := SeqAtomicTryLoad(seq, seq.BeginRead(), ptr); ok { - return val - } - } -} - -// SeqAtomicTryLoad returns a copy of *ptr while in a reader critical section -// in seq initiated by a call to seq.BeginRead() that returned epoch. If the -// read would race with a writer critical section, SeqAtomicTryLoad returns -// (unspecified, false). -// -//go:nosplit -func SeqAtomicTryLoad(seq *sync.SeqCount, epoch sync.SeqCountEpoch, ptr *Value) (val Value, ok bool) { - if sync.RaceEnabled { - // runtime.RaceDisable() doesn't actually stop the race detector, so it - // can't help us here. Instead, call runtime.memmove directly, which is - // not instrumented by the race detector. - gohacks.Memmove(unsafe.Pointer(&val), unsafe.Pointer(ptr), unsafe.Sizeof(val)) - } else { - // This is ~40% faster for short reads than going through memmove. - val = *ptr - } - ok = seq.ReadOk(epoch) - return -} diff --git a/pkg/sync/mutex_test.go b/pkg/sync/mutex_test.go deleted file mode 100644 index 4fb51a8ab..000000000 --- a/pkg/sync/mutex_test.go +++ /dev/null @@ -1,71 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package sync - -import ( - "sync" - "testing" - "unsafe" -) - -// TestStructSize verifies that syncMutex's size hasn't drifted from the -// standard library's version. -// -// The correctness of this package relies on these remaining in sync. -func TestStructSize(t *testing.T) { - const ( - got = unsafe.Sizeof(syncMutex{}) - want = unsafe.Sizeof(sync.Mutex{}) - ) - if got != want { - t.Errorf("got sizeof(syncMutex) = %d, want = sizeof(sync.Mutex) = %d", got, want) - } -} - -// TestFieldValues verifies that the semantics of syncMutex.state from the -// standard library's implementation. -// -// The correctness of this package relies on these remaining in sync. -func TestFieldValues(t *testing.T) { - var m Mutex - m.Lock() - if got := *m.m.state(); got != mutexLocked { - t.Errorf("got locked sync.Mutex.state = %d, want = %d", got, mutexLocked) - } - m.Unlock() - if got := *m.m.state(); got != mutexUnlocked { - t.Errorf("got unlocked sync.Mutex.state = %d, want = %d", got, mutexUnlocked) - } -} - -func TestDoubleTryLock(t *testing.T) { - var m Mutex - if !m.TryLock() { - t.Fatal("failed to aquire lock") - } - if m.TryLock() { - t.Fatal("unexpectedly succeeded in aquiring locked mutex") - } -} - -func TestTryLockAfterLock(t *testing.T) { - var m Mutex - m.Lock() - if m.TryLock() { - t.Fatal("unexpectedly succeeded in aquiring locked mutex") - } -} - -func TestTryLockUnlock(t *testing.T) { - var m Mutex - if !m.TryLock() { - t.Fatal("failed to aquire lock") - } - m.Unlock() - if !m.TryLock() { - t.Fatal("failed to aquire lock after unlock") - } -} diff --git a/pkg/sync/rwmutex_test.go b/pkg/sync/rwmutex_test.go deleted file mode 100644 index 5ca96d12b..000000000 --- a/pkg/sync/rwmutex_test.go +++ /dev/null @@ -1,205 +0,0 @@ -// Copyright 2009 The Go Authors. All rights reserved. -// Copyright 2019 The gVisor Authors. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// GOMAXPROCS=10 go test - -// Copy/pasted from the standard library's sync/rwmutex_test.go, except for the -// addition of downgradingWriter and the renaming of num_iterations to -// numIterations to shut up Golint. - -package sync - -import ( - "fmt" - "runtime" - "sync/atomic" - "testing" -) - -func parallelReader(m *RWMutex, clocked, cunlock, cdone chan bool) { - m.RLock() - clocked <- true - <-cunlock - m.RUnlock() - cdone <- true -} - -func doTestParallelReaders(numReaders, gomaxprocs int) { - runtime.GOMAXPROCS(gomaxprocs) - var m RWMutex - clocked := make(chan bool) - cunlock := make(chan bool) - cdone := make(chan bool) - for i := 0; i < numReaders; i++ { - go parallelReader(&m, clocked, cunlock, cdone) - } - // Wait for all parallel RLock()s to succeed. - for i := 0; i < numReaders; i++ { - <-clocked - } - for i := 0; i < numReaders; i++ { - cunlock <- true - } - // Wait for the goroutines to finish. - for i := 0; i < numReaders; i++ { - <-cdone - } -} - -func TestParallelReaders(t *testing.T) { - defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(-1)) - doTestParallelReaders(1, 4) - doTestParallelReaders(3, 4) - doTestParallelReaders(4, 2) -} - -func reader(rwm *RWMutex, numIterations int, activity *int32, cdone chan bool) { - for i := 0; i < numIterations; i++ { - rwm.RLock() - n := atomic.AddInt32(activity, 1) - if n < 1 || n >= 10000 { - panic(fmt.Sprintf("wlock(%d)\n", n)) - } - for i := 0; i < 100; i++ { - } - atomic.AddInt32(activity, -1) - rwm.RUnlock() - } - cdone <- true -} - -func writer(rwm *RWMutex, numIterations int, activity *int32, cdone chan bool) { - for i := 0; i < numIterations; i++ { - rwm.Lock() - n := atomic.AddInt32(activity, 10000) - if n != 10000 { - panic(fmt.Sprintf("wlock(%d)\n", n)) - } - for i := 0; i < 100; i++ { - } - atomic.AddInt32(activity, -10000) - rwm.Unlock() - } - cdone <- true -} - -func downgradingWriter(rwm *RWMutex, numIterations int, activity *int32, cdone chan bool) { - for i := 0; i < numIterations; i++ { - rwm.Lock() - n := atomic.AddInt32(activity, 10000) - if n != 10000 { - panic(fmt.Sprintf("wlock(%d)\n", n)) - } - for i := 0; i < 100; i++ { - } - atomic.AddInt32(activity, -10000) - rwm.DowngradeLock() - n = atomic.AddInt32(activity, 1) - if n < 1 || n >= 10000 { - panic(fmt.Sprintf("wlock(%d)\n", n)) - } - for i := 0; i < 100; i++ { - } - atomic.AddInt32(activity, -1) - rwm.RUnlock() - } - cdone <- true -} - -func HammerDowngradableRWMutex(gomaxprocs, numReaders, numIterations int) { - runtime.GOMAXPROCS(gomaxprocs) - // Number of active readers + 10000 * number of active writers. - var activity int32 - var rwm RWMutex - cdone := make(chan bool) - go writer(&rwm, numIterations, &activity, cdone) - go downgradingWriter(&rwm, numIterations, &activity, cdone) - var i int - for i = 0; i < numReaders/2; i++ { - go reader(&rwm, numIterations, &activity, cdone) - } - go writer(&rwm, numIterations, &activity, cdone) - go downgradingWriter(&rwm, numIterations, &activity, cdone) - for ; i < numReaders; i++ { - go reader(&rwm, numIterations, &activity, cdone) - } - // Wait for the 4 writers and all readers to finish. - for i := 0; i < 4+numReaders; i++ { - <-cdone - } -} - -func TestDowngradableRWMutex(t *testing.T) { - defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(-1)) - n := 1000 - if testing.Short() { - n = 5 - } - HammerDowngradableRWMutex(1, 1, n) - HammerDowngradableRWMutex(1, 3, n) - HammerDowngradableRWMutex(1, 10, n) - HammerDowngradableRWMutex(4, 1, n) - HammerDowngradableRWMutex(4, 3, n) - HammerDowngradableRWMutex(4, 10, n) - HammerDowngradableRWMutex(10, 1, n) - HammerDowngradableRWMutex(10, 3, n) - HammerDowngradableRWMutex(10, 10, n) - HammerDowngradableRWMutex(10, 5, n) -} - -func TestRWDoubleTryLock(t *testing.T) { - var rwm RWMutex - if !rwm.TryLock() { - t.Fatal("failed to aquire lock") - } - if rwm.TryLock() { - t.Fatal("unexpectedly succeeded in aquiring locked mutex") - } -} - -func TestRWTryLockAfterLock(t *testing.T) { - var rwm RWMutex - rwm.Lock() - if rwm.TryLock() { - t.Fatal("unexpectedly succeeded in aquiring locked mutex") - } -} - -func TestRWTryLockUnlock(t *testing.T) { - var rwm RWMutex - if !rwm.TryLock() { - t.Fatal("failed to aquire lock") - } - rwm.Unlock() - if !rwm.TryLock() { - t.Fatal("failed to aquire lock after unlock") - } -} - -func TestTryRLockAfterLock(t *testing.T) { - var rwm RWMutex - rwm.Lock() - if rwm.TryRLock() { - t.Fatal("unexpectedly succeeded in aquiring locked mutex") - } -} - -func TestTryLockAfterRLock(t *testing.T) { - var rwm RWMutex - rwm.RLock() - if rwm.TryLock() { - t.Fatal("unexpectedly succeeded in aquiring locked mutex") - } -} - -func TestDoubleTryRLock(t *testing.T) { - var rwm RWMutex - if !rwm.TryRLock() { - t.Fatal("failed to aquire lock") - } - if !rwm.TryRLock() { - t.Fatal("failed to read aquire read locked lock") - } -} diff --git a/pkg/sync/seqatomictest/BUILD b/pkg/sync/seqatomictest/BUILD deleted file mode 100644 index 5f9164117..000000000 --- a/pkg/sync/seqatomictest/BUILD +++ /dev/null @@ -1,32 +0,0 @@ -load("//tools:defs.bzl", "go_library", "go_test") -load("//tools/go_generics:defs.bzl", "go_template_instance") - -package(licenses = ["notice"]) - -go_template_instance( - name = "seqatomic_int", - out = "seqatomic_int_unsafe.go", - package = "seqatomic", - suffix = "Int", - template = "//pkg/sync:generic_seqatomic", - types = { - "Value": "int", - }, -) - -go_library( - name = "seqatomic", - srcs = ["seqatomic_int_unsafe.go"], - deps = [ - "//pkg/gohacks", - "//pkg/sync", - ], -) - -go_test( - name = "seqatomic_test", - size = "small", - srcs = ["seqatomic_test.go"], - library = ":seqatomic", - deps = ["//pkg/sync"], -) diff --git a/pkg/sync/seqatomictest/seqatomic_test.go b/pkg/sync/seqatomictest/seqatomic_test.go deleted file mode 100644 index 2c4568b07..000000000 --- a/pkg/sync/seqatomictest/seqatomic_test.go +++ /dev/null @@ -1,132 +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 seqatomic - -import ( - "sync/atomic" - "testing" - "time" - - "gvisor.dev/gvisor/pkg/sync" -) - -func TestSeqAtomicLoadUncontended(t *testing.T) { - var seq sync.SeqCount - const want = 1 - data := want - if got := SeqAtomicLoadInt(&seq, &data); got != want { - t.Errorf("SeqAtomicLoadInt: got %v, wanted %v", got, want) - } -} - -func TestSeqAtomicLoadAfterWrite(t *testing.T) { - var seq sync.SeqCount - var data int - const want = 1 - seq.BeginWrite() - data = want - seq.EndWrite() - if got := SeqAtomicLoadInt(&seq, &data); got != want { - t.Errorf("SeqAtomicLoadInt: got %v, wanted %v", got, want) - } -} - -func TestSeqAtomicLoadDuringWrite(t *testing.T) { - var seq sync.SeqCount - var data int - const want = 1 - seq.BeginWrite() - go func() { - time.Sleep(time.Second) - data = want - seq.EndWrite() - }() - if got := SeqAtomicLoadInt(&seq, &data); got != want { - t.Errorf("SeqAtomicLoadInt: got %v, wanted %v", got, want) - } -} - -func TestSeqAtomicTryLoadUncontended(t *testing.T) { - var seq sync.SeqCount - const want = 1 - data := want - epoch := seq.BeginRead() - if got, ok := SeqAtomicTryLoadInt(&seq, epoch, &data); !ok || got != want { - t.Errorf("SeqAtomicTryLoadInt: got (%v, %v), wanted (%v, true)", got, ok, want) - } -} - -func TestSeqAtomicTryLoadDuringWrite(t *testing.T) { - var seq sync.SeqCount - var data int - epoch := seq.BeginRead() - seq.BeginWrite() - if got, ok := SeqAtomicTryLoadInt(&seq, epoch, &data); ok { - t.Errorf("SeqAtomicTryLoadInt: got (%v, true), wanted (_, false)", got) - } - seq.EndWrite() -} - -func TestSeqAtomicTryLoadAfterWrite(t *testing.T) { - var seq sync.SeqCount - var data int - epoch := seq.BeginRead() - seq.BeginWrite() - seq.EndWrite() - if got, ok := SeqAtomicTryLoadInt(&seq, epoch, &data); ok { - t.Errorf("SeqAtomicTryLoadInt: got (%v, true), wanted (_, false)", got) - } -} - -func BenchmarkSeqAtomicLoadIntUncontended(b *testing.B) { - var seq sync.SeqCount - const want = 42 - data := want - b.RunParallel(func(pb *testing.PB) { - for pb.Next() { - if got := SeqAtomicLoadInt(&seq, &data); got != want { - b.Fatalf("SeqAtomicLoadInt: got %v, wanted %v", got, want) - } - } - }) -} - -func BenchmarkSeqAtomicTryLoadIntUncontended(b *testing.B) { - var seq sync.SeqCount - const want = 42 - data := want - b.RunParallel(func(pb *testing.PB) { - epoch := seq.BeginRead() - for pb.Next() { - if got, ok := SeqAtomicTryLoadInt(&seq, epoch, &data); !ok || got != want { - b.Fatalf("SeqAtomicTryLoadInt: got (%v, %v), wanted (%v, true)", got, ok, want) - } - } - }) -} - -// For comparison: -func BenchmarkAtomicValueLoadIntUncontended(b *testing.B) { - var a atomic.Value - const want = 42 - a.Store(int(want)) - b.RunParallel(func(pb *testing.PB) { - for pb.Next() { - if got := a.Load().(int); got != want { - b.Fatalf("atomic.Value.Load: got %v, wanted %v", got, want) - } - } - }) -} diff --git a/pkg/sync/seqcount_test.go b/pkg/sync/seqcount_test.go deleted file mode 100644 index 3f5592e3e..000000000 --- a/pkg/sync/seqcount_test.go +++ /dev/null @@ -1,100 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package sync - -import ( - "testing" - "time" -) - -func TestSeqCountWriteUncontended(t *testing.T) { - var seq SeqCount - seq.BeginWrite() - seq.EndWrite() -} - -func TestSeqCountReadUncontended(t *testing.T) { - var seq SeqCount - epoch := seq.BeginRead() - if !seq.ReadOk(epoch) { - t.Errorf("ReadOk: got false, wanted true") - } -} - -func TestSeqCountBeginReadAfterWrite(t *testing.T) { - var seq SeqCount - var data int32 - const want = 1 - seq.BeginWrite() - data = want - seq.EndWrite() - epoch := seq.BeginRead() - if data != want { - t.Errorf("Reader: got %v, wanted %v", data, want) - } - if !seq.ReadOk(epoch) { - t.Errorf("ReadOk: got false, wanted true") - } -} - -func TestSeqCountBeginReadDuringWrite(t *testing.T) { - var seq SeqCount - var data int - const want = 1 - seq.BeginWrite() - go func() { - time.Sleep(time.Second) - data = want - seq.EndWrite() - }() - epoch := seq.BeginRead() - if data != want { - t.Errorf("Reader: got %v, wanted %v", data, want) - } - if !seq.ReadOk(epoch) { - t.Errorf("ReadOk: got false, wanted true") - } -} - -func TestSeqCountReadOkAfterWrite(t *testing.T) { - var seq SeqCount - epoch := seq.BeginRead() - seq.BeginWrite() - seq.EndWrite() - if seq.ReadOk(epoch) { - t.Errorf("ReadOk: got true, wanted false") - } -} - -func TestSeqCountReadOkDuringWrite(t *testing.T) { - var seq SeqCount - epoch := seq.BeginRead() - seq.BeginWrite() - if seq.ReadOk(epoch) { - t.Errorf("ReadOk: got true, wanted false") - } - seq.EndWrite() -} - -func BenchmarkSeqCountWriteUncontended(b *testing.B) { - var seq SeqCount - for i := 0; i < b.N; i++ { - seq.BeginWrite() - seq.EndWrite() - } -} - -func BenchmarkSeqCountReadUncontended(b *testing.B) { - var seq SeqCount - b.RunParallel(func(pb *testing.PB) { - for pb.Next() { - epoch := seq.BeginRead() - if !seq.ReadOk(epoch) { - b.Fatalf("ReadOk: got false, wanted true") - } - } - }) -} |