From 243e76b3cc3e5fccdf9c021354d4a2d88b6bb707 Mon Sep 17 00:00:00 2001 From: Shannon Date: Fri, 3 Jan 2020 15:04:39 +1100 Subject: [PATCH] Removes ability to have recursive locks in SnapDictionary, changes logic to require locking around the methods just like ContentStore, updates tests --- .../Cache/SnapDictionaryTests.cs | 126 ++++++++------ .../PublishedCache/NuCache/ContentStore.cs | 104 ++++++------ .../NuCache/PublishedSnapshotService.cs | 14 +- .../PublishedCache/NuCache/SnapDictionary.cs | 154 ++++++++---------- 4 files changed, 204 insertions(+), 194 deletions(-) diff --git a/src/Umbraco.Tests/Cache/SnapDictionaryTests.cs b/src/Umbraco.Tests/Cache/SnapDictionaryTests.cs index b435af9e77..86426d196c 100644 --- a/src/Umbraco.Tests/Cache/SnapDictionaryTests.cs +++ b/src/Umbraco.Tests/Cache/SnapDictionaryTests.cs @@ -9,6 +9,47 @@ using Umbraco.Web.PublishedCache.NuCache.Snap; namespace Umbraco.Tests.Cache { + /// + /// Used for tests + /// + public static class SnapDictionaryExtensions + { + internal static void Set(this SnapDictionary d, TKey key, TValue value) + where TValue : class + { + using (d.GetScopedWriteLock(GetScopeProvider())) + { + d.SetLocked(key, value); + } + } + + internal static void Clear(this SnapDictionary d) + where TValue : class + { + using (d.GetScopedWriteLock(GetScopeProvider())) + { + d.ClearLocked(); + } + } + + internal static void Clear(this SnapDictionary d, TKey key) + where TValue : class + { + using (d.GetScopedWriteLock(GetScopeProvider())) + { + d.ClearLocked(key); + } + } + + private static IScopeProvider GetScopeProvider() + { + var scopeProvider = Mock.Of(); + Mock.Get(scopeProvider) + .Setup(x => x.Context).Returns(() => null); + return scopeProvider; + } + } + [TestFixture] public class SnapDictionaryTests { @@ -223,7 +264,7 @@ namespace Umbraco.Tests.Cache { var d = new SnapDictionary(); d.Test.CollectAuto = false; - + // gen 1 d.Set(1, "one"); Assert.AreEqual(1, d.Test.GetValues(1).Length); @@ -321,7 +362,7 @@ namespace Umbraco.Tests.Cache { var d = new SnapDictionary(); d.Test.CollectAuto = false; - + Assert.AreEqual(0, d.Test.GetValues(1).Length); // gen 1 @@ -416,7 +457,7 @@ namespace Umbraco.Tests.Cache { var d = new SnapDictionary(); d.Test.CollectAuto = false; - + // gen 1 d.Set(1, "one"); Assert.AreEqual(1, d.Test.GetValues(1).Length); @@ -578,7 +619,7 @@ namespace Umbraco.Tests.Cache { var d = new SnapDictionary(); d.Test.CollectAuto = false; - + d.Set(1, "one"); d.Set(2, "two"); @@ -689,7 +730,7 @@ namespace Umbraco.Tests.Cache { // gen 3 Assert.AreEqual(2, d.Test.GetValues(1).Length); - d.Set(1, "ein"); + d.SetLocked(1, "ein"); Assert.AreEqual(3, d.Test.GetValues(1).Length); Assert.AreEqual(3, d.Test.LiveGen); @@ -727,31 +768,25 @@ namespace Umbraco.Tests.Cache using (var w1 = d.GetScopedWriteLock(scopeProvider)) { Assert.AreEqual(1, t.LiveGen); - Assert.AreEqual(1, t.WLocked); + Assert.IsTrue(t.IsLocked); Assert.IsTrue(t.NextGen); - using (var w2 = d.GetScopedWriteLock(scopeProvider)) + Assert.Throws(() => { - Assert.AreEqual(1, t.LiveGen); - Assert.AreEqual(2, t.WLocked); - Assert.IsTrue(t.NextGen); - - Assert.AreNotSame(w1, w2); // get a new writer each time - - d.Set(1, "one"); - - Assert.AreEqual(0, d.CreateSnapshot().Gen); - } + using (var w2 = d.GetScopedWriteLock(scopeProvider)) + { + } + }); Assert.AreEqual(1, t.LiveGen); - Assert.AreEqual(1, t.WLocked); + Assert.IsTrue(t.IsLocked); Assert.IsTrue(t.NextGen); Assert.AreEqual(0, d.CreateSnapshot().Gen); } Assert.AreEqual(1, t.LiveGen); - Assert.AreEqual(0, t.WLocked); + Assert.IsFalse(t.IsLocked); Assert.IsTrue(t.NextGen); Assert.AreEqual(1, d.CreateSnapshot().Gen); @@ -772,11 +807,14 @@ namespace Umbraco.Tests.Cache using (var w1 = d.GetScopedWriteLock(scopeProvider)) { + // This one is interesting, although we don't allow recursive locks, since this is + // using the same ScopeContext/key, the lock acquisition is only done once + using (var w2 = d.GetScopedWriteLock(scopeProvider)) { Assert.AreSame(w1, w2); - d.Set(1, "one"); + d.SetLocked(1, "one"); } } } @@ -797,19 +835,16 @@ namespace Umbraco.Tests.Cache using (var w1 = d.GetScopedWriteLock(scopeProvider1)) { Assert.AreEqual(1, t.LiveGen); - Assert.AreEqual(1, t.WLocked); + Assert.IsTrue(t.IsLocked); Assert.IsTrue(t.NextGen); - using (var w2 = d.GetScopedWriteLock(scopeProvider2)) + Assert.Throws(() => { - Assert.AreEqual(1, t.LiveGen); - Assert.AreEqual(2, t.WLocked); - Assert.IsTrue(t.NextGen); + using (var w2 = d.GetScopedWriteLock(scopeProvider2)) + { + } + }); - Assert.AreNotSame(w1, w2); - - d.Set(1, "one"); - } } } @@ -848,13 +883,13 @@ namespace Umbraco.Tests.Cache Assert.IsFalse(d.Test.NextGen); Assert.AreEqual("uno", s2.Get(1)); - var scopeProvider = GetScopeProvider(); + var scopeProvider = GetScopeProvider(); using (d.GetScopedWriteLock(scopeProvider)) { // gen 3 Assert.AreEqual(2, d.Test.GetValues(1).Length); - d.Set(1, "ein"); + d.SetLocked(1, "ein"); Assert.AreEqual(3, d.Test.GetValues(1).Length); Assert.AreEqual(3, d.Test.LiveGen); @@ -881,6 +916,7 @@ namespace Umbraco.Tests.Cache { var d = new SnapDictionary(); d.Test.CollectAuto = false; + // gen 1 d.Set(1, "one"); @@ -894,12 +930,11 @@ namespace Umbraco.Tests.Cache Assert.AreEqual("uno", s2.Get(1)); var scopeProvider = GetScopeProvider(); - using (d.GetScopedWriteLock(scopeProvider)) { // creating a snapshot in a write-lock does NOT return the "current" content // it uses the previous snapshot, so new snapshot created only on release - d.Set(1, "ein"); + d.SetLocked(1, "ein"); var s3 = d.CreateSnapshot(); Assert.AreEqual(2, s3.Gen); Assert.AreEqual("uno", s3.Get(1)); @@ -934,12 +969,11 @@ namespace Umbraco.Tests.Cache var scopeContext = new ScopeContext(); var scopeProvider = GetScopeProvider(scopeContext); - using (d.GetScopedWriteLock(scopeProvider)) { // creating a snapshot in a write-lock does NOT return the "current" content // it uses the previous snapshot, so new snapshot created only on release - d.Set(1, "ein"); + d.SetLocked(1, "ein"); var s3 = d.CreateSnapshot(); Assert.AreEqual(2, s3.Gen); Assert.AreEqual("uno", s3.Get(1)); @@ -967,7 +1001,7 @@ namespace Umbraco.Tests.Cache var d = new SnapDictionary(); var t = d.Test; t.CollectAuto = false; - + // gen 1 d.Set(1, "one"); var s1 = d.CreateSnapshot(); @@ -984,12 +1018,11 @@ namespace Umbraco.Tests.Cache var scopeContext = new ScopeContext(); var scopeProvider = GetScopeProvider(scopeContext); - using (d.GetScopedWriteLock(scopeProvider)) { // creating a snapshot in a write-lock does NOT return the "current" content // it uses the previous snapshot, so new snapshot created only on release - d.Set(1, "ein"); + d.SetLocked(1, "ein"); var s3 = d.CreateSnapshot(); Assert.AreEqual(2, s3.Gen); Assert.AreEqual("uno", s3.Get(1)); @@ -997,7 +1030,7 @@ namespace Umbraco.Tests.Cache // we made some changes, so a next gen is required Assert.AreEqual(3, t.LiveGen); Assert.IsTrue(t.NextGen); - Assert.AreEqual(1, t.WLocked); + Assert.IsTrue(t.IsLocked); // but live snapshot contains changes var ls = t.LiveSnapshot; @@ -1008,7 +1041,7 @@ namespace Umbraco.Tests.Cache // nothing is committed until scope exits Assert.AreEqual(3, t.LiveGen); Assert.IsTrue(t.NextGen); - Assert.AreEqual(1, t.WLocked); + Assert.IsTrue(t.IsLocked); // no changes until exit var s4 = d.CreateSnapshot(); @@ -1020,7 +1053,7 @@ namespace Umbraco.Tests.Cache // now things have changed Assert.AreEqual(2, t.LiveGen); Assert.IsFalse(t.NextGen); - Assert.AreEqual(0, t.WLocked); + Assert.IsFalse(t.IsLocked); // no changes since not completed var s5 = d.CreateSnapshot(); @@ -1097,9 +1130,10 @@ namespace Umbraco.Tests.Cache // writer is scope contextual and scoped // when disposed, nothing happens // when the context exists, the writer is released + using (d.GetScopedWriteLock(scopeProvider)) { - d.Set(1, "ein"); + d.SetLocked(1, "ein"); Assert.IsTrue(d.Test.NextGen); Assert.AreEqual(3, d.Test.LiveGen); Assert.IsNotNull(d.Test.GenObj); @@ -1107,7 +1141,7 @@ namespace Umbraco.Tests.Cache } // writer has not released - Assert.AreEqual(1, d.Test.WLocked); + Assert.IsTrue(d.Test.IsLocked); Assert.IsNotNull(d.Test.GenObj); Assert.AreEqual(2, d.Test.GenObj.Gen); @@ -1118,7 +1152,7 @@ namespace Umbraco.Tests.Cache // panic! var s2 = d.CreateSnapshot(); - Assert.AreEqual(1, d.Test.WLocked); + Assert.IsTrue(d.Test.IsLocked); Assert.IsNotNull(d.Test.GenObj); Assert.AreEqual(2, d.Test.GenObj.Gen); Assert.AreEqual(3, d.Test.LiveGen); @@ -1127,7 +1161,7 @@ namespace Umbraco.Tests.Cache // release writer scopeContext.ScopeExit(true); - Assert.AreEqual(0, d.Test.WLocked); + Assert.IsFalse(d.Test.IsLocked); Assert.IsNotNull(d.Test.GenObj); Assert.AreEqual(2, d.Test.GenObj.Gen); Assert.AreEqual(3, d.Test.LiveGen); @@ -1135,7 +1169,7 @@ namespace Umbraco.Tests.Cache var s3 = d.CreateSnapshot(); - Assert.AreEqual(0, d.Test.WLocked); + Assert.IsFalse(d.Test.IsLocked); Assert.IsNotNull(d.Test.GenObj); Assert.AreEqual(3, d.Test.GenObj.Gen); Assert.AreEqual(3, d.Test.LiveGen); diff --git a/src/Umbraco.Web/PublishedCache/NuCache/ContentStore.cs b/src/Umbraco.Web/PublishedCache/NuCache/ContentStore.cs index 82fae0d32a..17eb2b6457 100644 --- a/src/Umbraco.Web/PublishedCache/NuCache/ContentStore.cs +++ b/src/Umbraco.Web/PublishedCache/NuCache/ContentStore.cs @@ -39,7 +39,6 @@ namespace Umbraco.Web.PublishedCache.NuCache private long _liveGen, _floorGen; private bool _nextGen, _collectAuto; private Task _collectTask; - private volatile int _wlocked; private List> _wchanges; // TODO: collection trigger (ok for now) @@ -83,7 +82,6 @@ namespace Umbraco.Web.PublishedCache.NuCache private class WriteLockInfo { public bool Taken; - public bool Count; } // a scope contextual that represents a locked writer to the dictionary @@ -111,7 +109,6 @@ namespace Umbraco.Web.PublishedCache.NuCache // TODO: GetScopedWriter? should the dict have a ref onto the scope provider? public IDisposable GetScopedWriteLock(IScopeProvider scopeProvider) { - _logger.Debug("GetScopedWriteLock"); return ScopeContextualBase.Get(scopeProvider, _instanceId, scoped => new ScopedWriteLock(this, scoped)); } @@ -123,6 +120,9 @@ namespace Umbraco.Web.PublishedCache.NuCache private void Lock(WriteLockInfo lockInfo, bool forceGen = false) { + if (Monitor.IsEntered(_wlocko)) + throw new InvalidOperationException("Recursive locks not allowed"); + Monitor.Enter(_wlocko, ref lockInfo.Taken); lock(_rlocko) @@ -131,9 +131,7 @@ namespace Umbraco.Web.PublishedCache.NuCache try { } finally { - _wlocked++; - lockInfo.Count = true; - if (_nextGen == false || (forceGen && _wlocked == 1)) + if (_nextGen == false || (forceGen)) { // because we are changing things, a new generation // is created, which will trigger a new snapshot @@ -179,12 +177,6 @@ namespace Umbraco.Web.PublishedCache.NuCache _localDb.Commit(); } - // TODO: Shouldn't this be in a finally block? - // TODO: Shouldn't this be decremented after we exit?? - // TODO: Shouldn't the locked flag never exceed 1? - if (lockInfo.Count) - _wlocked--; - // TODO: Shouldn't this be in a finally block? if (lockInfo.Taken) Monitor.Exit(_wlocko); @@ -220,22 +212,18 @@ namespace Umbraco.Web.PublishedCache.NuCache public void ReleaseLocalDb() { - _logger.Info("Releasing DB..."); var lockInfo = new WriteLockInfo(); try { try { - // Trying to lock could throw exceptions so always make sure to clean up. - _logger.Info("Trying to lock before releasing DB (lock count = {LockCount}) ...", _wlocked); - + // Trying to lock could throw exceptions so always make sure to clean up. Lock(lockInfo); } finally { try { - _logger.Info("Disposing local DB..."); _localDb?.Dispose(); } catch (Exception ex) @@ -275,57 +263,61 @@ namespace Umbraco.Web.PublishedCache.NuCache #region Content types - public void NewContentTypes(IEnumerable types) + /// + /// Sets data for new content types + /// + /// + /// + /// This methods MUST be called from within a write lock, normally wrapped within GetScopedWriteLock + /// otherwise an exception will occur. + /// + /// + /// Thrown if this method is not called within a write lock + /// + public void NewContentTypesLocked(IEnumerable types) { - var lockInfo = new WriteLockInfo(); - try - { - _logger.Debug("NewContentTypes"); - Lock(lockInfo); + EnsureLocked(); - foreach (var type in types) - { - SetValueLocked(_contentTypesById, type.Id, type); - SetValueLocked(_contentTypesByAlias, type.Alias, type); - } - } - finally + foreach (var type in types) { - Release(lockInfo); + SetValueLocked(_contentTypesById, type.Id, type); + SetValueLocked(_contentTypesByAlias, type.Alias, type); } } - public void UpdateContentTypes(IEnumerable types) + /// + /// Sets data for updated content types + /// + /// + /// + /// This methods MUST be called from within a write lock, normally wrapped within GetScopedWriteLock + /// otherwise an exception will occur. + /// + /// + /// Thrown if this method is not called within a write lock + /// + public void UpdateContentTypesLocked(IEnumerable types) { //nothing to do if this is empty, no need to lock/allocate/iterate/etc... if (!types.Any()) return; - var lockInfo = new WriteLockInfo(); - try + EnsureLocked(); + + var index = types.ToDictionary(x => x.Id, x => x); + + foreach (var type in index.Values) { - _logger.Debug("UpdateContentTypes"); - Lock(lockInfo); - - var index = types.ToDictionary(x => x.Id, x => x); - - foreach (var type in index.Values) - { - SetValueLocked(_contentTypesById, type.Id, type); - SetValueLocked(_contentTypesByAlias, type.Alias, type); - } - - foreach (var link in _contentNodes.Values) - { - var node = link.Value; - if (node == null) continue; - var contentTypeId = node.ContentType.Id; - if (index.TryGetValue(contentTypeId, out var contentType) == false) continue; - SetValueLocked(_contentNodes, node.Id, new ContentNode(node, contentType)); - } + SetValueLocked(_contentTypesById, type.Id, type); + SetValueLocked(_contentTypesByAlias, type.Alias, type); } - finally + + foreach (var link in _contentNodes.Values) { - Release(lockInfo); + var node = link.Value; + if (node == null) continue; + var contentTypeId = node.ContentType.Id; + if (index.TryGetValue(contentTypeId, out var contentType) == false) continue; + SetValueLocked(_contentNodes, node.Id, new ContentNode(node, contentType)); } } @@ -1256,7 +1248,7 @@ namespace Umbraco.Web.PublishedCache.NuCache // else we need to try to create a new gen ref // whether we are wlocked or not, noone can rlock while we do, // so _liveGen and _nextGen are safe - if (_wlocked > 0) // volatile, cannot ++ but could -- + if (Monitor.IsEntered(_wlocko)) { // write-locked, cannot use latest gen (at least 1) so use previous var snapGen = _nextGen ? _liveGen - 1 : _liveGen; diff --git a/src/Umbraco.Web/PublishedCache/NuCache/PublishedSnapshotService.cs b/src/Umbraco.Web/PublishedCache/NuCache/PublishedSnapshotService.cs index b761fe0fa4..249eb882f9 100755 --- a/src/Umbraco.Web/PublishedCache/NuCache/PublishedSnapshotService.cs +++ b/src/Umbraco.Web/PublishedCache/NuCache/PublishedSnapshotService.cs @@ -622,7 +622,7 @@ namespace Umbraco.Web.PublishedCache.NuCache .Where(x => x.RootContentId.HasValue && x.LanguageIsoCode.IsNullOrWhiteSpace() == false) .Select(x => new Domain(x.Id, x.DomainName, x.RootContentId.Value, CultureInfo.GetCultureInfo(x.LanguageIsoCode), x.IsWildcard))) { - _domainStore.Set(domain.Id, domain); + _domainStore.SetLocked(domain.Id, domain); } } @@ -980,7 +980,7 @@ namespace Umbraco.Web.PublishedCache.NuCache } break; case DomainChangeTypes.Remove: - _domainStore.Clear(payload.Id); + _domainStore.ClearLocked(payload.Id); break; case DomainChangeTypes.Refresh: var domain = _serviceContext.DomainService.GetById(payload.Id); @@ -988,7 +988,7 @@ namespace Umbraco.Web.PublishedCache.NuCache if (domain.RootContentId.HasValue == false) continue; // anomaly if (domain.LanguageIsoCode.IsNullOrWhiteSpace()) continue; // anomaly var culture = CultureInfo.GetCultureInfo(domain.LanguageIsoCode); - _domainStore.Set(domain.Id, new Domain(domain.Id, domain.DomainName, domain.RootContentId.Value, culture, domain.IsWildcard)); + _domainStore.SetLocked(domain.Id, new Domain(domain.Id, domain.DomainName, domain.RootContentId.Value, culture, domain.IsWildcard)); break; } } @@ -1075,9 +1075,9 @@ namespace Umbraco.Web.PublishedCache.NuCache _contentStore.UpdateContentTypes(removedIds, typesA, kits); if (!otherIds.IsCollectionEmpty()) - _contentStore.UpdateContentTypes(CreateContentTypes(PublishedItemType.Content, otherIds.ToArray())); + _contentStore.UpdateContentTypesLocked(CreateContentTypes(PublishedItemType.Content, otherIds.ToArray())); if (!newIds.IsCollectionEmpty()) - _contentStore.NewContentTypes(CreateContentTypes(PublishedItemType.Content, newIds.ToArray())); + _contentStore.NewContentTypesLocked(CreateContentTypes(PublishedItemType.Content, newIds.ToArray())); scope.Complete(); } } @@ -1106,9 +1106,9 @@ namespace Umbraco.Web.PublishedCache.NuCache _mediaStore.UpdateContentTypes(removedIds, typesA, kits); if (!otherIds.IsCollectionEmpty()) - _mediaStore.UpdateContentTypes(CreateContentTypes(PublishedItemType.Media, otherIds.ToArray()).ToArray()); + _mediaStore.UpdateContentTypesLocked(CreateContentTypes(PublishedItemType.Media, otherIds.ToArray()).ToArray()); if (!newIds.IsCollectionEmpty()) - _mediaStore.NewContentTypes(CreateContentTypes(PublishedItemType.Media, newIds.ToArray()).ToArray()); + _mediaStore.NewContentTypesLocked(CreateContentTypes(PublishedItemType.Media, newIds.ToArray()).ToArray()); scope.Complete(); } } diff --git a/src/Umbraco.Web/PublishedCache/NuCache/SnapDictionary.cs b/src/Umbraco.Web/PublishedCache/NuCache/SnapDictionary.cs index e0ad26eb81..c38940da25 100644 --- a/src/Umbraco.Web/PublishedCache/NuCache/SnapDictionary.cs +++ b/src/Umbraco.Web/PublishedCache/NuCache/SnapDictionary.cs @@ -35,7 +35,6 @@ namespace Umbraco.Web.PublishedCache.NuCache private long _liveGen, _floorGen; private bool _nextGen, _collectAuto; private Task _collectTask; - private volatile int _wlocked; // minGenDelta to be adjusted // we may want to throttle collects even if delta is reached @@ -84,7 +83,6 @@ namespace Umbraco.Web.PublishedCache.NuCache private class WriteLockInfo { public bool Taken; - public bool Count; } // a scope contextual that represents a locked writer to the dictionary @@ -92,8 +90,7 @@ namespace Umbraco.Web.PublishedCache.NuCache { private readonly WriteLockInfo _lockinfo = new WriteLockInfo(); private readonly SnapDictionary _dictionary; - private int _released; - + public ScopedWriteLock(SnapDictionary dictionary, bool scoped) { _dictionary = dictionary; @@ -102,8 +99,6 @@ namespace Umbraco.Web.PublishedCache.NuCache public override void Release(bool completed) { - if (Interlocked.CompareExchange(ref _released, 1, 0) != 0) - return; _dictionary.Release(_lockinfo, completed); } } @@ -117,8 +112,17 @@ namespace Umbraco.Web.PublishedCache.NuCache return ScopeContextualBase.Get(scopeProvider, _instanceId, scoped => new ScopedWriteLock(this, scoped)); } + private void EnsureLocked() + { + if (!Monitor.IsEntered(_wlocko)) + throw new InvalidOperationException("Write lock must be acquried."); + } + private void Lock(WriteLockInfo lockInfo, bool forceGen = false) { + if (Monitor.IsEntered(_wlocko)) + throw new InvalidOperationException("Recursive locks not allowed"); + Monitor.Enter(_wlocko, ref lockInfo.Taken); lock(_rlocko) @@ -132,11 +136,7 @@ namespace Umbraco.Web.PublishedCache.NuCache try { } finally { - // increment the lock count, and register that this lock is counting - _wlocked++; - lockInfo.Count = true; - - if (_nextGen == false || (forceGen && _wlocked == 1)) + if (_nextGen == false || (forceGen)) { // because we are changing things, a new generation // is created, which will trigger a new snapshot @@ -181,8 +181,7 @@ namespace Umbraco.Web.PublishedCache.NuCache } } - // decrement the lock count, if counting, then exit the lock - if (lockInfo.Count) _wlocked--; + // TODO: Shouldn't this be in a finally block? Monitor.Exit(_wlocko); } @@ -198,75 +197,59 @@ namespace Umbraco.Web.PublishedCache.NuCache return link; } - public void Set(TKey key, TValue value) + public void SetLocked(TKey key, TValue value) { - var lockInfo = new WriteLockInfo(); - try - { - Lock(lockInfo); + EnsureLocked(); - // this is safe only because we're write-locked - var link = GetHead(key); - if (link != null) + // this is safe only because we're write-locked + var link = GetHead(key); + if (link != null) + { + // already in the dict + if (link.Gen != _liveGen) { - // already in the dict - if (link.Gen != _liveGen) - { - // for an older gen - if value is different then insert a new - // link for the new gen, with the new value - if (link.Value != value) - _items.TryUpdate(key, new LinkedNode(value, _liveGen, link), link); - } - else - { - // for the live gen - we can fix the live gen - and remove it - // if value is null and there's no next gen - if (value == null && link.Next == null) - _items.TryRemove(key, out link); - else - link.Value = value; - } + // for an older gen - if value is different then insert a new + // link for the new gen, with the new value + if (link.Value != value) + _items.TryUpdate(key, new LinkedNode(value, _liveGen, link), link); } else { - _items.TryAdd(key, new LinkedNode(value, _liveGen)); - } - } - finally - { - Release(lockInfo); - } - } - - public void Clear(TKey key) - { - Set(key, null); - } - - public void Clear() - { - var lockInfo = new WriteLockInfo(); - try - { - Lock(lockInfo); - - // this is safe only because we're write-locked - foreach (var kvp in _items.Where(x => x.Value != null)) - { - if (kvp.Value.Gen < _liveGen) - { - var link = new LinkedNode(null, _liveGen, kvp.Value); - _items.TryUpdate(kvp.Key, link, kvp.Value); - } + // for the live gen - we can fix the live gen - and remove it + // if value is null and there's no next gen + if (value == null && link.Next == null) + _items.TryRemove(key, out link); else - { - kvp.Value.Value = null; - } + link.Value = value; } } - finally + else { - Release(lockInfo); + _items.TryAdd(key, new LinkedNode(value, _liveGen)); + } + } + + public void ClearLocked(TKey key) + { + SetLocked(key, null); + } + + public void ClearLocked() + { + EnsureLocked(); + + // this is safe only because we're write-locked + foreach (var kvp in _items.Where(x => x.Value != null)) + { + if (kvp.Value.Gen < _liveGen) + { + var link = new LinkedNode(null, _liveGen, kvp.Value); + _items.TryUpdate(kvp.Key, link, kvp.Value); + } + else + { + kvp.Value.Value = null; + } } } @@ -336,7 +319,7 @@ namespace Umbraco.Web.PublishedCache.NuCache // else we need to try to create a new gen object // whether we are wlocked or not, noone can rlock while we do, // so _liveGen and _nextGen are safe - if (_wlocked > 0) // volatile, cannot ++ but could -- + if (Monitor.IsEntered(_wlocko)) { // write-locked, cannot use latest gen (at least 1) so use previous var snapGen = _nextGen ? _liveGen - 1 : _liveGen; @@ -468,17 +451,18 @@ namespace Umbraco.Web.PublishedCache.NuCache } } - public /*async*/ Task PendingCollect() - { - Task task; - lock (_rlocko) - { - task = _collectTask; - } - return task ?? Task.CompletedTask; - //if (task != null) - // await task; - } + // TODO: This is never used? Should it be? Maybe move to TestHelper below? + //public /*async*/ Task PendingCollect() + //{ + // Task task; + // lock (_rlocko) + // { + // task = _collectTask; + // } + // return task ?? Task.CompletedTask; + // //if (task != null) + // // await task; + //} public long GenCount => _genObjs.Count; @@ -503,7 +487,7 @@ namespace Umbraco.Web.PublishedCache.NuCache public long LiveGen => _dict._liveGen; public long FloorGen => _dict._floorGen; public bool NextGen => _dict._nextGen; - public int WLocked => _dict._wlocked; + public bool IsLocked => Monitor.IsEntered(_dict._wlocko); public bool CollectAuto {