Event Tracing for Windows

Event tracing in its simplest form uses the system Event Log. (Computer Management, Event Viewer).

A more complex use is WPA/WPR Windows Performance Recorder and Analyser, available on the Windows Performance Toolkit https://learn.microsoft.com/en-us/windows-hardware/test/wpt/

You can download the Windows Performance Toolkit through https://learn.microsoft.com/en-gb/windows-hardware/get-started/adk-install

Architecture

A driver which produces such logs is registered with the system with an xml file, which identifies the source of the logs, and the form they take (data types), names, and other details.

The xml file is in the project Resource Files folder.

The xml is processed by the Message Compiler by adding this to the project file in each ItemDefinitionGroup (ie, Debug|ARM64 and Release|ARM64)

<MessageCompile>
  <HeaderFilePath>.\\</HeaderFilePath>
  <RCFilePath>.\\</RCFilePath>
  <GenerateKernelModeLoggingMacros>true</GenerateKernelModeLoggingMacros>
  <UseBaseNameOfInput>true</UseBaseNameOfInput>
</MessageCompile>

The generated header file is then included in the source code, and the generated binary file is added to the end of the resources file like this:

LANGUAGE 0x9,0x1
1 11 "Wperf_DriverETW_schema_MSG00001.bin"
1 WEVT_TEMPLATE "Wperf_driverETW_schemaTEMP.BIN"

Registering

This xml file is copied with the driver to the system32\drivers directory, and needs to be registered with the system on install with wevtutil.exe im Wperf_DriverETW_schema.xml from the drivers directory.

To unregister call wevtutil.exe um Wperf_DriverETW_schema.xml.

Viewing logs

Open Event Viewer. Right click Custom View and select Create Custom View.

Click OK, give it a useful name, and OK again.

You will be presented with logs like this

Windows Performance Recorder / Windows Performance Analyzer

Windows Performance Recorder is a tool to enable/disable the recording of trace acquisition. You can configure it either via a GUI or CLI wpr.

You can either use default profiles for recording or create your own custom profiles which use the .wprp extension but are just normal xml files.

After selecting the set of profiles just click Start and it will start tracing.

After the workload runs you can click Save which will create a .etl file that you can open on WPA. It will somewhat look like this

Adding ETW support to the driver

You need to add an Instrumentation Manifest to all applications that make calls to EventWrite* outputting events to ETW or a log channel. The manifest defines all the type of events and providers. You should compile your manifest with the Message Compiler (Message Compiler (MC.exe) - Win32 apps | Microsoft Learn)

Documentation says that inside the Windows SDK there is the tool ECManGen.exe which is a GUI to facilitate writing mainfests however this link Windows 10 SDK Preview Build 16267 and Mobile Emulator Build 15240 Released - Windows Developer Blog shows that the tool was removed.

Sample manifest

<instrumentationManifest
    xmlns="http://schemas.microsoft.com/win/2004/08/events" 
    xmlns:win="http://manifests.microsoft.com/win/2004/08/windows/events"
    xmlns:xs="http://www.w3.org/2001/XMLSchema"
    >

    <instrumentation>
        <events>
            <provider ...>
                <channels>
                    <importChannel .../>
                    <channel .../>
                </channels>
                <levels>
                    <level .../>
                </levels>
                <tasks>
                    <task .../>
                </tasks>
                <opcodes>
                    <opcode .../>
                </opcodes>
                <keywords>
                    <keyword .../>
                </keywords>
                <filters>
                    <filter .../>
                </filters>
                <maps>
                    <valueMap ...>
                        <map .../>
                    </valueMap>
                    <bitMap ...>
                        <map .../>
                    </bitMap>
                </maps>
                <templates>
                    <template ...>
                        <data .../>
                        <UserData>
                            <!-- valid XML fragment -->
                        </UserData>
                    </template>
                </templates>
                <events>
                    <event .../>
                </events>
            </provider>
        </events>
    </instrumentation>

    <localization>
        <resources ...>
            <stringTable>
                <string id="" value=""/>
            </stringTable>
        </resources>
    </localization>

</instrumentationManifest>

Some of this entries are optional e.g. tasks and opcodes are for organizational purposes.

Defining events

DRAFT

“If administrators will be consuming your events using a tool like Windows Event Viewer, then you must set the channel attribute.”

Events that have more than a single message seem to need a message template. You can define an event template like so

                    <template tid="t4">
                        <data name="FilesCount" inType="win:UInt16" />
                        <data name="Files" inType="win:UnicodeString" count="FilesCount"/>
                        <data name="Path" inType="win:UnicodeString" />
                    </template>

And the event to use it like so

                    <event value="3"
                        level="NotValid"
                        keywords="Local Write"
                        task="Validate"
                        opcode="Cleanup"
                        template="t4"
                        channel="c2"
                        symbol="TEMPFILE_CLEANUP_EVENT"
                        message ="$(string.Event.TempFilesNotDeleted)"/>

Custom `.wprp`and how to plug the driver

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Running traces for PMU counters

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