diff options
Diffstat (limited to 'src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs')
| -rw-r--r-- | src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs | 665 |
1 files changed, 0 insertions, 665 deletions
diff --git a/src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs b/src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs deleted file mode 100644 index 1a1f5fa2c0..0000000000 --- a/src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs +++ /dev/null @@ -1,665 +0,0 @@ -// Licensed to the .NET Foundation under one or more agreements. -// The .NET Foundation licenses this file to you under the MIT license. -// See the LICENSE file in the project root for more information. - -using System; -using System.Diagnostics; -using System.Threading; -#if !ES_BUILD_AGAINST_DOTNET_V35 -using Contract = System.Diagnostics.Contracts.Contract; -#else -using Contract = Microsoft.Diagnostics.Contracts.Internal.Contract; -#endif - -#if ES_BUILD_STANDALONE -namespace Microsoft.Diagnostics.Tracing -#else -using System.Threading.Tasks; -namespace System.Diagnostics.Tracing -#endif -{ - /// <summary> - /// Tracks activities. This is meant to be a singleton (accessed by the ActivityTracer.Instance static property) - /// - /// Logically this is simply holds the m_current variable that holds the async local that holds the current ActivityInfo - /// An ActivityInfo is represents a activity (which knows its creator and thus knows its path). - /// - /// Most of the magic is in the async local (it gets copied to new tasks) - /// - /// On every start event call OnStart - /// - /// Guid activityID; - /// Guid relatedActivityID; - /// if (OnStart(activityName, out activityID, out relatedActivityID, ForceStop, options)) - /// // Log Start event with activityID and relatedActivityID - /// - /// On every stop event call OnStop - /// - /// Guid activityID; - /// if (OnStop(activityName, ref activityID ForceStop)) - /// // Stop event with activityID - /// - /// On any normal event log the event with activityTracker.CurrentActivityId - /// </summary> - internal class ActivityTracker - { - - /// <summary> - /// Called on work item begins. The activity name = providerName + activityName without 'Start' suffix. - /// It updates CurrentActivityId to track. - /// - /// It returns true if the Start should be logged, otherwise (if it is illegal recursion) it return false. - /// - /// The start event should use as its activity ID the CurrentActivityId AFTER calling this routine and its - /// RelatedActivityID the CurrentActivityId BEFORE calling this routine (the creator). - /// - /// If activity tracing is not on, then activityId and relatedActivityId are not set - /// </summary> - public void OnStart(string providerName, string activityName, int task, ref Guid activityId, ref Guid relatedActivityId, EventActivityOptions options) - { - if (m_current == null) // We are not enabled - { - // We used to rely on the TPL provider turning us on, but that has the disadvantage that you don't get Start-Stop tracking - // until you use Tasks for the first time (which you may never do). Thus we change it to pull rather tan push for whether - // we are enabled. - if (m_checkedForEnable) - return; - m_checkedForEnable = true; - if (TplEtwProvider.Log.IsEnabled(EventLevel.Informational, TplEtwProvider.Keywords.TasksFlowActivityIds)) - Enable(); - if (m_current == null) - return; - } - - - Debug.Assert((options & EventActivityOptions.Disable) == 0); - - var currentActivity = m_current.Value; - var fullActivityName = NormalizeActivityName(providerName, activityName, task); - - var etwLog = TplEtwProvider.Log; - if (etwLog.Debug) - { - etwLog.DebugFacilityMessage("OnStartEnter", fullActivityName); - etwLog.DebugFacilityMessage("OnStartEnterActivityState", ActivityInfo.LiveActivities(currentActivity)); - } - - if (currentActivity != null) - { - // Stop activity tracking if we reached the maximum allowed depth - if (currentActivity.m_level >= MAX_ACTIVITY_DEPTH) - { - activityId = Guid.Empty; - relatedActivityId = Guid.Empty; - if (etwLog.Debug) - etwLog.DebugFacilityMessage("OnStartRET", "Fail"); - return; - } - // Check for recursion, and force-stop any activities if the activity already started. - if ((options & EventActivityOptions.Recursive) == 0) - { - ActivityInfo existingActivity = FindActiveActivity(fullActivityName, currentActivity); - if (existingActivity != null) - { - OnStop(providerName, activityName, task, ref activityId); - currentActivity = m_current.Value; - } - } - } - - // Get a unique ID for this activity. - long id; - if (currentActivity == null) - id = Interlocked.Increment(ref m_nextId); - else - id = Interlocked.Increment(ref currentActivity.m_lastChildID); - - // The previous ID is my 'causer' and becomes my related activity ID - relatedActivityId = EventSource.CurrentThreadActivityId; - - // Add to the list of started but not stopped activities. - ActivityInfo newActivity = new ActivityInfo(fullActivityName, id, currentActivity, relatedActivityId, options); - m_current.Value = newActivity; - - // Remember the current ID so we can log it - activityId = newActivity.ActivityId; - - if (etwLog.Debug) - { - etwLog.DebugFacilityMessage("OnStartRetActivityState", ActivityInfo.LiveActivities(newActivity)); - etwLog.DebugFacilityMessage1("OnStartRet", activityId.ToString(), relatedActivityId.ToString()); - } - } - - /// <summary> - /// Called when a work item stops. The activity name = providerName + activityName without 'Stop' suffix. - /// It updates m_current variable to track this fact. The Stop event associated with stop should log the ActivityID associated with the event. - /// - /// If activity tracing is not on, then activityId and relatedActivityId are not set - /// </summary> - public void OnStop(string providerName, string activityName, int task, ref Guid activityId) - { - if (m_current == null) // We are not enabled - return; - - var fullActivityName = NormalizeActivityName(providerName, activityName, task); - - var etwLog = TplEtwProvider.Log; - if (etwLog.Debug) - { - etwLog.DebugFacilityMessage("OnStopEnter", fullActivityName); - etwLog.DebugFacilityMessage("OnStopEnterActivityState", ActivityInfo.LiveActivities(m_current.Value)); - } - - for (; ; ) // This is a retry loop. - { - ActivityInfo currentActivity = m_current.Value; - ActivityInfo newCurrentActivity = null; // if we have seen any live activities (orphans), at he first one we have seen. - - // Search to find the activity to stop in one pass. This insures that we don't let one mistake - // (stopping something that was not started) cause all active starts to be stopped - // By first finding the target start to stop we are more robust. - ActivityInfo activityToStop = FindActiveActivity(fullActivityName, currentActivity); - - // ignore stops where we can't find a start because we may have popped them previously. - if (activityToStop == null) - { - activityId = Guid.Empty; - // TODO add some logging about this. Basically could not find matching start. - if (etwLog.Debug) - etwLog.DebugFacilityMessage("OnStopRET", "Fail"); - return; - } - - activityId = activityToStop.ActivityId; - - // See if there are any orphans that need to be stopped. - ActivityInfo orphan = currentActivity; - while (orphan != activityToStop && orphan != null) - { - if (orphan.m_stopped != 0) // Skip dead activities. - { - orphan = orphan.m_creator; - continue; - } - if (orphan.CanBeOrphan()) - { - // We can't pop anything after we see a valid orphan, remember this for later when we update m_current. - if (newCurrentActivity == null) - newCurrentActivity = orphan; - } - else - { - orphan.m_stopped = 1; - Debug.Assert(orphan.m_stopped != 0); - } - orphan = orphan.m_creator; - } - - // try to Stop the activity atomically. Other threads may be trying to do this as well. - if (Interlocked.CompareExchange(ref activityToStop.m_stopped, 1, 0) == 0) - { - // I succeeded stopping this activity. Now we update our m_current pointer - - // If I haven't yet determined the new current activity, it is my creator. - if (newCurrentActivity == null) - newCurrentActivity = activityToStop.m_creator; - - m_current.Value = newCurrentActivity; - - if (etwLog.Debug) - { - etwLog.DebugFacilityMessage("OnStopRetActivityState", ActivityInfo.LiveActivities(newCurrentActivity)); - etwLog.DebugFacilityMessage("OnStopRet", activityId.ToString()); - } - return; - } - // We failed to stop it. We must have hit a race to stop it. Just start over and try again. - } - } - - /// <summary> - /// Turns on activity tracking. It is sticky, once on it stays on (race issues otherwise) - /// </summary> - public void Enable() - { - if (m_current == null) - { - // Catch the not Implemented - try - { - m_current = new AsyncLocal<ActivityInfo>(ActivityChanging); - } - catch (NotImplementedException) { -#if (!ES_BUILD_PCL && ! PROJECTN) - // send message to debugger without delay - System.Diagnostics.Debugger.Log(0, null, "Activity Enabled() called but AsyncLocals Not Supported (pre V4.6). Ignoring Enable"); -#endif - } - } - } - - /// <summary> - /// An activity tracker is a singleton, this is how you get the one and only instance. - /// </summary> - public static ActivityTracker Instance { get { return s_activityTrackerInstance; } } - - - #region private - - /// <summary> - /// The current activity ID. Use this to log normal events. - /// </summary> - private Guid CurrentActivityId { get { return m_current.Value.ActivityId; } } - - /// <summary> - /// Searched for a active (nonstopped) activity with the given name. Returns null if not found. - /// </summary> - private ActivityInfo FindActiveActivity(string name, ActivityInfo startLocation) - { - var activity = startLocation; - while (activity != null) - { - if (name == activity.m_name && activity.m_stopped == 0) - return activity; - activity = activity.m_creator; - } - return null; - } - - /// <summary> - /// Strip out "Start" or "End" suffix from activity name and add providerName prefix. - /// If 'task' it does not end in Start or Stop and Task is non-zero use that as the name of the activity - /// </summary> - private string NormalizeActivityName(string providerName, string activityName, int task) - { - if (activityName.EndsWith(EventSource.s_ActivityStartSuffix, StringComparison.Ordinal)) - activityName = activityName.Substring(0, activityName.Length - EventSource.s_ActivityStartSuffix.Length); - else if (activityName.EndsWith(EventSource.s_ActivityStopSuffix, StringComparison.Ordinal)) - activityName = activityName.Substring(0, activityName.Length - EventSource.s_ActivityStopSuffix.Length); - else if (task != 0) - activityName = "task" + task.ToString(); - - // We use provider name to distinguish between activities from different providers. - return providerName + activityName; - } - - // ******************************************************************************* - /// <summary> - /// An ActivityInfo represents a particular activity. It is almost read-only. The only - /// fields that change after creation are - /// m_lastChildID - used to generate unique IDs for the children activities and for the most part can be ignored. - /// m_stopped - indicates that this activity is dead - /// This read-only-ness is important because an activity's m_creator chain forms the - /// 'Path of creation' for the activity (which is also its unique ID) but is also used as - /// the 'list of live parents' which indicate of those ancestors, which are alive (if they - /// are not marked dead they are alive). - /// </summary> - private class ActivityInfo - { - public ActivityInfo(string name, long uniqueId, ActivityInfo creator, Guid activityIDToRestore, EventActivityOptions options) - { - m_name = name; - m_eventOptions = options; - m_creator = creator; - m_uniqueId = uniqueId; - m_level = creator != null ? creator.m_level + 1 : 0; - m_activityIdToRestore = activityIDToRestore; - - // Create a nice GUID that encodes the chain of activities that started this one. - CreateActivityPathGuid(out m_guid, out m_activityPathGuidOffset); - } - - public Guid ActivityId - { - get - { - return m_guid; - } - } - - public static string Path(ActivityInfo activityInfo) - { - if (activityInfo == null) - return (""); - return Path(activityInfo.m_creator) + "/" + activityInfo.m_uniqueId.ToString(); - } - - public override string ToString() - { - return m_name + "(" + Path(this) + (m_stopped != 0 ? ",DEAD)" : ")"); - } - - public static string LiveActivities(ActivityInfo list) - { - if (list == null) - return ""; - return list.ToString() + ";" + LiveActivities(list.m_creator); - } - - public bool CanBeOrphan() - { - if ((m_eventOptions & EventActivityOptions.Detachable) != 0) - return true; - return false; - } - - #region private - - #region CreateActivityPathGuid - /// <summary> - /// Logically every activity Path (see Path()) that describes the activities that caused this - /// (rooted in an activity that predates activity tracking. - /// - /// We wish to encode this path in the Guid to the extent that we can. Many of the paths have - /// many small numbers in them and we take advantage of this in the encoding to output as long - /// a path in the GUID as possible. - /// - /// Because of the possibility of GUID collision, we only use 96 of the 128 bits of the GUID - /// for encoding the path. The last 32 bits are a simple checksum (and random number) that - /// identifies this as using the convention defined here. - /// - /// It returns both the GUID which has the path as well as the offset that points just beyond - /// the end of the activity (so it can be appended to). Note that if the end is in a nibble - /// (it uses nibbles instead of bytes as the unit of encoding, then it will point at the unfinished - /// byte (since the top nibble can't be zero you can determine if this is true by seeing if - /// this byte is nonZero. This offset is needed to efficiently create the ID for child activities. - /// </summary> - private unsafe void CreateActivityPathGuid(out Guid idRet, out int activityPathGuidOffset) - { - fixed (Guid* outPtr = &idRet) - { - int activityPathGuidOffsetStart = 0; - if (m_creator != null) - { - activityPathGuidOffsetStart = m_creator.m_activityPathGuidOffset; - idRet = m_creator.m_guid; - } - else - { - // TODO FIXME - differentiate between AD inside PCL - int appDomainID = 0; -#if (!ES_BUILD_STANDALONE && !PROJECTN) - appDomainID = System.Threading.Thread.GetDomainID(); -#endif - // We start with the appdomain number to make this unique among appdomains. - activityPathGuidOffsetStart = AddIdToGuid(outPtr, activityPathGuidOffsetStart, (uint)appDomainID); - } - - activityPathGuidOffset = AddIdToGuid(outPtr, activityPathGuidOffsetStart, (uint)m_uniqueId); - - - // If the path does not fit, Make a GUID by incrementing rather than as a path, keeping as much of the path as possible - if (12 < activityPathGuidOffset) - CreateOverflowGuid(outPtr); - } - } - - /// <summary> - /// If we can't fit the activity Path into the GUID we come here. What we do is simply - /// generate a 4 byte number (s_nextOverflowId). Then look for an ancestor that has - /// sufficient space for this ID. By doing this, we preserve the fact that this activity - /// is a child (of unknown depth) from that ancestor. - /// </summary> - private unsafe void CreateOverflowGuid(Guid* outPtr) - { - // Search backwards for an ancestor that has sufficient space to put the ID. - for (ActivityInfo ancestor = m_creator; ancestor != null; ancestor = ancestor.m_creator) - { - if (ancestor.m_activityPathGuidOffset <= 10) // we need at least 2 bytes. - { - uint id = unchecked((uint)Interlocked.Increment(ref ancestor.m_lastChildID)); // Get a unique ID - // Try to put the ID into the GUID - *outPtr = ancestor.m_guid; - int endId = AddIdToGuid(outPtr, ancestor.m_activityPathGuidOffset, id, true); - - // Does it fit? - if (endId <= 12) - break; - } - } - } - - /// <summary> - /// The encoding for a list of numbers used to make Activity GUIDs. Basically - /// we operate on nibbles (which are nice because they show up as hex digits). The - /// list is ended with a end nibble (0) and depending on the nibble value (Below) - /// the value is either encoded into nibble itself or it can spill over into the - /// bytes that follow. - /// </summary> - enum NumberListCodes : byte - { - End = 0x0, // ends the list. No valid value has this prefix. - LastImmediateValue = 0xA, - - PrefixCode = 0xB, // all the 'long' encodings go here. If the next nibble is MultiByte1-4 - // than this is a 'overflow' id. Unlike the hierarchical IDs these are - // allocated densely but don't tell you anything about nesting. we use - // these when we run out of space in the GUID to store the path. - - MultiByte1 = 0xC, // 1 byte follows. If this Nibble is in the high bits, it the high bits of the number are stored in the low nibble. - // commented out because the code does not explicitly reference the names (but they are logically defined). - // MultiByte2 = 0xD, // 2 bytes follow (we don't bother with the nibble optimization) - // MultiByte3 = 0xE, // 3 bytes follow (we don't bother with the nibble optimization) - // MultiByte4 = 0xF, // 4 bytes follow (we don't bother with the nibble optimization) - } - - /// Add the activity id 'id' to the output Guid 'outPtr' starting at the offset 'whereToAddId' - /// Thus if this number is 6 that is where 'id' will be added. This will return 13 (12 - /// is the maximum number of bytes that fit in a GUID) if the path did not fit. - /// If 'overflow' is true, then the number is encoded as an 'overflow number (which has a - /// special (longer prefix) that indicates that this ID is allocated differently - private static unsafe int AddIdToGuid(Guid* outPtr, int whereToAddId, uint id, bool overflow = false) - { - byte* ptr = (byte*)outPtr; - byte* endPtr = ptr + 12; - ptr += whereToAddId; - if (endPtr <= ptr) - return 13; // 12 means we might exactly fit, 13 means we definately did not fit - - if (0 < id && id <= (uint)NumberListCodes.LastImmediateValue && !overflow) - WriteNibble(ref ptr, endPtr, id); - else - { - uint len = 4; - if (id <= 0xFF) - len = 1; - else if (id <= 0xFFFF) - len = 2; - else if (id <= 0xFFFFFF) - len = 3; - - if (overflow) - { - if (endPtr <= ptr + 2) // I need at least 2 bytes - return 13; - - // Write out the prefix code nibble and the length nibble - WriteNibble(ref ptr, endPtr, (uint)NumberListCodes.PrefixCode); - } - // The rest is the same for overflow and non-overflow case - WriteNibble(ref ptr, endPtr, (uint)NumberListCodes.MultiByte1 + (len - 1)); - - // Do we have an odd nibble? If so flush it or use it for the 12 byte case. - if (ptr < endPtr && *ptr != 0) - { - // If the value < 4096 we can use the nibble we are otherwise just outputting as padding. - if (id < 4096) - { - // Indicate this is a 1 byte multicode with 4 high order bits in the lower nibble. - *ptr = (byte)(((uint)NumberListCodes.MultiByte1 << 4) + (id >> 8)); - id &= 0xFF; // Now we only want the low order bits. - } - ptr++; - } - - // Write out the bytes. - while (0 < len) - { - if (endPtr <= ptr) - { - ptr++; // Indicate that we have overflowed - break; - } - *ptr++ = (byte)id; - id = (id >> 8); - --len; - } - } - - // Compute the checksum - uint* sumPtr = (uint*)outPtr; - // We set the last DWORD the sum of the first 3 DWORDS in the GUID. This - sumPtr[3] = sumPtr[0] + sumPtr[1] + sumPtr[2] + 0x599D99AD; // This last number is a random number (it identifies us as us) - - return (int)(ptr - ((byte*)outPtr)); - } - - /// <summary> - /// Write a single Nible 'value' (must be 0-15) to the byte buffer represented by *ptr. - /// Will not go past 'endPtr'. Also it assumes that we never write 0 so we can detect - /// whether a nibble has already been written to ptr because it will be nonzero. - /// Thus if it is non-zero it adds to the current byte, otherwise it advances and writes - /// the new byte (in the high bits) of the next byte. - /// </summary> - private static unsafe void WriteNibble(ref byte* ptr, byte* endPtr, uint value) - { - Debug.Assert(0 <= value && value < 16); - Debug.Assert(ptr < endPtr); - - if (*ptr != 0) - *ptr++ |= (byte)value; - else - *ptr = (byte)(value << 4); - } - - #endregion // CreateGuidForActivityPath - - readonly internal string m_name; // The name used in the 'start' and 'stop' APIs to help match up - readonly long m_uniqueId; // a small number that makes this activity unique among its siblings - internal readonly Guid m_guid; // Activity Guid, it is basically an encoding of the Path() (see CreateActivityPathGuid) - internal readonly int m_activityPathGuidOffset; // Keeps track of where in m_guid the causality path stops (used to generated child GUIDs) - internal readonly int m_level; // current depth of the Path() of the activity (used to keep recursion under control) - readonly internal EventActivityOptions m_eventOptions; // Options passed to start. - internal long m_lastChildID; // used to create a unique ID for my children activities - internal int m_stopped; // This work item has stopped - readonly internal ActivityInfo m_creator; // My parent (creator). Forms the Path() for the activity. - readonly internal Guid m_activityIdToRestore; // The Guid to restore after a stop. - #endregion - } - - // This callback is used to initialize the m_current AsyncLocal Variable. - // Its job is to keep the ETW Activity ID (part of thread local storage) in sync - // with m_current.ActivityID - void ActivityChanging(AsyncLocalValueChangedArgs<ActivityInfo> args) - { - ActivityInfo cur = args.CurrentValue; - ActivityInfo prev = args.PreviousValue; - - // Are we popping off a value? (we have a prev, and it creator is cur) - // Then check if we should use the GUID at the time of the start event - if (prev != null && prev.m_creator == cur) - { - // If the saved activity ID is not the same as the creator activity - // that takes precedence (it means someone explicitly did a SetActivityID) - // Set it to that and get out - if (cur == null || prev.m_activityIdToRestore != cur.ActivityId) - { - EventSource.SetCurrentThreadActivityId(prev.m_activityIdToRestore); - return; - } - } - - // OK we did not have an explicit SetActivityID set. Then we should be - // setting the activity to current ActivityInfo. However that activity - // might be dead, in which case we should skip it, so we never set - // the ID to dead things. - while (cur != null) - { - // We found a live activity (typically the first time), set it to that. - if (cur.m_stopped == 0) - { - EventSource.SetCurrentThreadActivityId(cur.ActivityId); - return; - } - cur = cur.m_creator; - } - // we can get here if there is no information on our activity stack (everything is dead) - // currently we do nothing, as that seems better than setting to Guid.Emtpy. - } - - /// <summary> - /// Async local variables have the property that the are automatically copied whenever a task is created and used - /// while that task is running. Thus m_current 'flows' to any task that is caused by the current thread that - /// last set it. - /// - /// This variable points a a linked list that represents all Activities that have started but have not stopped. - /// </summary> - AsyncLocal<ActivityInfo> m_current; - bool m_checkedForEnable; - - // Singleton - private static ActivityTracker s_activityTrackerInstance = new ActivityTracker(); - - // Used to create unique IDs at the top level. Not used for nested Ids (each activity has its own id generator) - static long m_nextId = 0; - private const ushort MAX_ACTIVITY_DEPTH = 100; // Limit maximum depth of activities to be tracked at 100. - // This will avoid leaking memory in case of activities that are never stopped. - - #endregion - } - -#if ES_BUILD_STANDALONE || PROJECTN - /******************************** SUPPORT *****************************/ - /// <summary> - /// This is supplied by the framework. It is has the semantics that the value is copied to any new Tasks that is created - /// by the current task. Thus all causally related code gets this value. Note that reads and writes to this VARIABLE - /// (not what it points it) to this does not need to be protected by locks because it is inherently thread local (you always - /// only get your thread local copy which means that you never have races. - /// </summary> - /// -#if ES_BUILD_STANDALONE - [EventSource(Name = "Microsoft.Tasks.Nuget")] -#else - [EventSource(Name = "System.Diagnostics.Tracing.TplEtwProvider")] -#endif - internal class TplEtwProvider : EventSource - { - public class Keywords - { - public const EventKeywords TasksFlowActivityIds = (EventKeywords)0x80; - public const EventKeywords Debug = (EventKeywords)0x20000; - } - - public static TplEtwProvider Log = new TplEtwProvider(); - public bool Debug { get { return IsEnabled(EventLevel.Verbose, Keywords.Debug); } } - - public void DebugFacilityMessage(string Facility, string Message) { WriteEvent(1, Facility, Message); } - public void DebugFacilityMessage1(string Facility, string Message, string Arg) { WriteEvent(2, Facility, Message, Arg); } - public void SetActivityId(Guid Id) { WriteEvent(3, Id); } - } -#endif - -#if ES_BUILD_AGAINST_DOTNET_V35 || ES_BUILD_PCL || NO_ASYNC_LOCAL - // In these cases we don't have any Async local support. Do nothing. - internal sealed class AsyncLocalValueChangedArgs<T> - { - public T PreviousValue { get { return default(T); } } - public T CurrentValue { get { return default(T); } } - - } - - internal sealed class AsyncLocal<T> - { - public AsyncLocal(Action<AsyncLocalValueChangedArgs<T>> valueChangedHandler) { - throw new NotImplementedException("AsyncLocal only available on V4.6 and above"); - } - public T Value - { - get { return default(T); } - set { } - } - } -#endif - -} |