/// <summary>
/// Stops collector with the given sessionName.
/// </summary>
/// <param name="collectorName">
/// Name of the collector to be stopped.
/// </param>
/// <returns>
/// True if the operation succeeded, false otherwise.
/// </returns>
public static bool StopCollector(string collectorName)
{
const string MethodName = "StopCollector";
if (string.IsNullOrEmpty(collectorName))
{
throw new ArgumentException("collectorName cannot be null or empty.", "collectorName");
}
Logger.Log(
LoggerLevel.Info,
LogId,
MethodName,
"Attempting to stop ETW session [{0}]",
collectorName);
if (!EtwSessionManager.Stop(collectorName))
{
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Failed to stop ETW session [{0}]",
collectorName);
return(false);
}
Logger.Log(
LoggerLevel.Info,
LogId,
MethodName,
"ETW session [{0}] was stopped",
collectorName);
return(true);
}
/// <summary>
/// Checks if an existing ETW session satisfies the given collector configuration.
/// </summary>
/// <param name="config">
/// Configuration that should be checked against the existing ETW session.
/// </param>
/// <returns>
/// True if the existing session satisfies the given configuration, false otherwise.
/// </returns>
internal static bool ExistingSessionSatisfiesProviders(CollectorConfiguration config)
{
// Ok, the session is already in place, just check the providers
bool providersOk = false;
NativeMethods.EventTraceProperties sessionProperties;
if (EtwSessionManager.TryGetSessionProperties(config.Name, out sessionProperties))
{
providersOk = true;
// Loop over providers and ensure that they are good
var loggerId = sessionProperties.Wnode.HistoricalContext;
foreach (var provider in config.Providers)
{
NativeMethods.TraceEnableInfo providerInSession;
providersOk = EtwSessionManager.GetProviderInfo(loggerId, provider.Value.Id, out providerInSession) &&
providerInSession.IsEnabled != 0 &&
provider.Value.Level <= (EtwTraceLevel)providerInSession.Level &&
(provider.Value.KeywordsAll | providerInSession.MatchAllKeyword) == provider.Value.KeywordsAll &&
(provider.Value.KeywordsAny & providerInSession.MatchAnyKeyword) == provider.Value.KeywordsAny;
if (!providersOk)
{
// pass the native type to a provider to get a nice string representing the
// current settings
var providerConfigInSession = new ProviderConfiguration(
provider.Value.Id,
(EtwTraceLevel)providerInSession.Level,
providerInSession.MatchAnyKeyword,
providerInSession.MatchAllKeyword);
Logger.Log(
LoggerLevel.Error,
LogId,
"ExistingSessionSatisfiesProviders",
"Provider configuration [{0}] is not satisfied in ETW session [{1}]. Actual provider settings in session: {2}",
provider.Value,
config.Name,
providerInSession.IsEnabled == 0 ? "provider not enabled" : providerConfigInSession.ToString());
}
}
}
return(providersOk);
}
/// <summary>
/// Starts the collector with the given configuration.
/// </summary>
/// <param name="config">
/// The configuration of the collector to be started.
/// </param>
/// <returns>
/// The complete list with the back log of ETL files associated to the collector from oldest to newest.
/// </returns>
public List <string> StartCollector(CollectorConfiguration config)
{
const string MethodName = "StartCollector";
var etlBacklog = new List <string>();
// If a deprecated session exists try to shut it down
NativeMethods.EventTraceProperties traceProperties;
if (!string.IsNullOrEmpty(config.DeprecatedCollector))
{
StopCollector(config.DeprecatedCollector);
}
var clockType = config.ClockType == ClockType.Default ? ClockType.Perf : config.ClockType;
var preExistingSession = false;
if (EtwSessionManager.TryGetSessionProperties(this.Name, out traceProperties))
{
if ((NativeMethods.EtwSessionClockType)clockType == traceProperties.Wnode.ClientContext)
{
// Old session can be re-used.
preExistingSession = true;
}
else
{
// Old session needs to be stopped. Note that if stop failed there is a follow up check to ensure that
// the error was not due to the session being stopped between the checks.
if (!StopCollector(this.Name))
{
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Failed to stop existing trace session [{0}]. Cannot proceed to correctly update session.",
this.Name);
return(etlBacklog);
}
}
}
StringBuilder sb = new StringBuilder(256);
sb.AppendFormat(
CultureInfo.InvariantCulture,
"{0} \"{1}\" -nb {2} {3} -bs {4} -ft {5} -ct {6} -ets ",
preExistingSession ? "update" : "start",
config.Name,
config.MinBufferCount.ToString(CultureInfo.InvariantCulture),
config.MaxBufferCount.ToString(CultureInfo.InvariantCulture),
config.BufferSizeKB.ToString(CultureInfo.InvariantCulture),
config.FlushTimerSec.ToString(CultureInfo.InvariantCulture),
clockType);
if (config.SessionType == SessionType.Realtime)
{
sb.Append("-rt");
}
else
{
// Add parameters for proper ETL file rotation
this.isFileCollector = true;
this.maxFileCount = config.MaxFileCount;
this.maxFileSizeKB = config.MaxFileSizeMB * 1024;
this.maxFileTimeSpan = config.MaxFileTimeSpan;
this.etlBaseName = config.OriginalName;
this.EtlLogsDirectory = Path.Combine(this.baseEtlLocation, config.OriginalName);
if (!ProtectedIO(
() => Directory.CreateDirectory(this.EtlLogsDirectory),
e =>
{
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Failed to create directory [{0}] for collector [{1}]. Exception: {2}",
this.EtlLogsDirectory,
config.Name,
e);
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Failed to create or update ETW session [{0}]",
config.Name);
}))
{
return(etlBacklog);
}
// Get the full list of available ETL files, it will be trimmed according to success of update command.
etlBacklog = this.GetExistingEtlFiles();
this.currentEtlSessionFile = this.GenerateNextSessionFileName();
sb.AppendFormat(CultureInfo.InvariantCulture, "-mode Sequential -o \"{0}\"", this.currentEtlSessionFile);
if (config.SessionType == SessionType.FileAndRealtime ||
config.SessionType == SessionType.RealtimeAndFile)
{
sb.Append(" -rt");
}
}
var exitCode = RunCommand("logman", sb.ToString());
this.lastRotationTime = DateTime.UtcNow;
if (exitCode != ExitCodeSuccess)
{
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Logman failed to create or update ETW session [{0}].",
config.Name);
if (preExistingSession)
{
if (config.SessionType != SessionType.Realtime)
{
if (!EtwSessionManager.TryGetCurrentFileOfSession(config.Name, out this.currentEtlSessionFile))
{
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Failed to retrieve name of the ETL being used by ETW session [{0}].",
config.Name);
}
if (etlBacklog.Count > 0 &&
string.Compare(
etlBacklog.Last(), this.currentEtlSessionFile, StringComparison.OrdinalIgnoreCase) == 0)
{
etlBacklog.RemoveAt(etlBacklog.Count - 1);
Logger.Log(
LoggerLevel.Warning,
LogId,
MethodName,
"Current ETL file removed from backlog list since it is still in use. ETL File [{0}]",
this.currentEtlSessionFile);
}
}
Logger.Log(
LoggerLevel.Info,
LogId,
MethodName,
"Attempting to mitigate with pre-existing session...");
if (!ExistingSessionSatisfiesProviders(config))
{
Logger.Log(
LoggerLevel.Error,
LogId,
"StartCollector",
"Pre-existing session cannot be used since it does not satisfy the config.");
}
else
{
Logger.Log(
LoggerLevel.Error,
LogId,
MethodName,
"Using pre-existing ETW session since it satisfied the configuration.");
exitCode = ExitCodeSuccess;
}
}
}
if (exitCode == ExitCodeSuccess || preExistingSession)
{
Logger.Log(
LoggerLevel.Info,
LogId,
MethodName,
"ETW session is in place call UpdateProviders to enable them.");
}
etlBacklog.Sort(StringComparer.OrdinalIgnoreCase);
return(etlBacklog);
}
