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diff --git a/tools/profiler/public/ETWTools.h b/tools/profiler/public/ETWTools.h
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+++ b/tools/profiler/public/ETWTools.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef ETWTools_h
+#define ETWTools_h
+
+#include "mozilla/BaseProfilerMarkers.h"
+#include "mozilla/TimeStamp.h"
+#include "nsString.h"
+
+#if defined(XP_WIN) && !defined(RUST_BINDGEN) && !defined(__MINGW32__)
+#  include "mozilla/ProfilerState.h"
+
+#  include <windows.h>
+#  include <TraceLoggingProvider.h>
+#  include <vector>
+
+namespace ETW {
+
+extern std::atomic<ULONGLONG> gETWCollectionMask;
+
+// Forward-declare the g_hMyComponentProvider variable that you will use for
+// tracing in this component
+TRACELOGGING_DECLARE_PROVIDER(kFirefoxTraceLoggingProvider);
+
+void Init();
+void Shutdown();
+
+// This describes the base fields for all markers (information extracted from
+// MarkerOptions.
+struct BaseMarkerDescription {
+  using MS = mozilla::MarkerSchema;
+  static constexpr MS::PayloadField PayloadFields[] = {
+      {"StartTime", MS::InputType::TimeStamp, "Start Time"},
+      {"EndTime", MS::InputType::TimeStamp, "End Time"},
+      {"InnerWindowId", MS::InputType::Uint64, "Inner Window ID"},
+      {"CategoryPair", MS::InputType::Uint32, "Category Pair"}};
+};
+
+// This is the MarkerType object for markers with no statically declared type,
+// their name is written dynamically.
+struct SimpleMarkerType {
+  using MS = mozilla::MarkerSchema;
+  static constexpr const char* Name = "SimpleMarker";
+  static constexpr MS::PayloadField PayloadFields[] = {
+      {"MarkerName", MS::InputType::CString, "Simple Marker Name"}};
+};
+
+// This gets the space required in the Tlg static struct to pack the fields.
+template <typename T>
+constexpr std::size_t GetPackingSpace() {
+  size_t length = 0;
+  for (size_t i = 0; i < std::size(T::PayloadFields); i++) {
+    length += std::string_view{T::PayloadFields[i].Key}.size() + 1;
+    length += sizeof(uint8_t);
+  }
+  return length;
+}
+
+// Convert our InputType to Tlgs input type.
+constexpr uint8_t GetTlgInputType(mozilla::MarkerSchema::InputType aInput) {
+  using InputType = mozilla::MarkerSchema::InputType;
+  switch (aInput) {
+    case InputType::Boolean:
+      return TlgInUINT8;
+    case InputType::Uint32:
+      return TlgInUINT32;
+    case InputType::Uint64:
+    case InputType::TimeStamp:
+    case InputType::TimeDuration:
+      return TlgInUINT64;
+    case InputType::CString:
+      return TlgInANSISTRING;
+    case InputType::String:
+      return TlgInUNICODESTRING;
+    default:
+      return 0;
+  }
+}
+
+// This class represents the format ETW TraceLogging uses to describe its
+// metadata. Since we have an abstraction layer we need to statically
+// declare this ourselves and we cannot rely on TraceLogging's official
+// macros. This does mean if TraceLogging ships big changes (on an SDK update)
+// we may need to adapt.
+__pragma(pack(push, 1)) _tlgEvtTagDecl(0);
+template <typename T>
+struct StaticMetaData {
+  _tlgEventMetadata_t metaData;
+  _tlgEvtTagType _tlgEvtTag;
+  char name[std::string_view{T::Name}.size() + 1];
+  char fieldStorage[GetPackingSpace<BaseMarkerDescription>() +
+                    GetPackingSpace<T>()];
+
+  // constexpr constructor
+  constexpr StaticMetaData()
+      : metaData{_TlgBlobEvent4,
+                 11,  // WINEVENT_CHANNEL_TRACELOGGING,
+                 5,   // Verbose
+                 0,
+                 0,
+                 sizeof(StaticMetaData) - _tlg_EVENT_METADATA_PREAMBLE - 1},
+        _tlgEvtTag(_tlgEvtTagInit) {
+    for (uint32_t i = 0; i < std::string_view{T::Name}.size() + 1; i++) {
+      name[i] = T::Name[i];
+    }
+
+    size_t pos = 0;
+    for (uint32_t i = 0; i < std::size(BaseMarkerDescription::PayloadFields);
+         i++) {
+      for (size_t c = 0;
+           c < std::string_view{BaseMarkerDescription::PayloadFields[i].Key}
+                       .size() +
+                   1;
+           c++) {
+        fieldStorage[pos++] = BaseMarkerDescription::PayloadFields[i].Key[c];
+      }
+      fieldStorage[pos++] =
+          GetTlgInputType(BaseMarkerDescription::PayloadFields[i].InputTy);
+    }
+    for (uint32_t i = 0; i < std::size(T::PayloadFields); i++) {
+      for (size_t c = 0;
+           c < std::string_view{T::PayloadFields[i].Key}.size() + 1; c++) {
+        fieldStorage[pos++] = T::PayloadFields[i].Key[c];
+      }
+      fieldStorage[pos++] = GetTlgInputType(T::PayloadFields[i].InputTy);
+    }
+  }
+};
+__pragma(pack(pop));
+
+// This defines the amount of storage available on the stack to store POD
+// values.
+const size_t kStackStorage = 512;
+
+struct PayloadBuffer {
+  EVENT_DATA_DESCRIPTOR* mDescriptors = nullptr;
+  size_t mOffset = 0;
+  std::array<char, kStackStorage> mStorage;
+};
+
+// This processes POD objects and stores them in a temporary buffer.
+// Theoretically we could probably avoid these assignments when passed a POD
+// variable we know is going to be alive but that would require some more
+// template magic.
+template <typename T>
+static void CreateDataDescForPayload(PayloadBuffer& aBuffer,
+                                     EVENT_DATA_DESCRIPTOR& aDescriptor,
+                                     const T& aPayload) {
+  static_assert(std::is_pod<T>::value,
+                "Writing a non-POD payload requires template specialization.");
+
+  // Ensure we never overflow our stack buffer.
+  MOZ_RELEASE_ASSERT((aBuffer.mOffset + sizeof(T)) < kStackStorage);
+
+  T* storedValue =
+      reinterpret_cast<T*>(aBuffer.mStorage.data() + aBuffer.mOffset);
+  *storedValue = aPayload;
+  aBuffer.mOffset += sizeof(T);
+
+  EventDataDescCreate(&aDescriptor, storedValue, sizeof(T));
+}
+
+template <>
+inline void CreateDataDescForPayload<mozilla::ProfilerString8View>(
+    PayloadBuffer& aBuffer, EVENT_DATA_DESCRIPTOR& aDescriptor,
+    const mozilla::ProfilerString8View& aPayload) {
+  EventDataDescCreate(&aDescriptor, aPayload.StringView().data(),
+                      aPayload.StringView().size() + 1);
+}
+
+template <>
+inline void CreateDataDescForPayload<mozilla::TimeStamp>(
+    PayloadBuffer& aBuffer, EVENT_DATA_DESCRIPTOR& aDescriptor,
+    const mozilla::TimeStamp& aPayload) {
+  if (aPayload.RawQueryPerformanceCounterValue().isNothing()) {
+    // This should never happen?
+    EventDataDescCreate(&aDescriptor, nullptr, 0);
+    return;
+  }
+
+  CreateDataDescForPayload(aBuffer, aDescriptor,
+                           aPayload.RawQueryPerformanceCounterValue().value());
+}
+
+template <>
+inline void CreateDataDescForPayload<mozilla::TimeDuration>(
+    PayloadBuffer& aBuffer, EVENT_DATA_DESCRIPTOR& aDescriptor,
+    const mozilla::TimeDuration& aPayload) {
+  CreateDataDescForPayload(aBuffer, aDescriptor, aPayload.ToMilliseconds());
+}
+
+// For reasons that are beyond me if this isn't marked inline it generates an
+// unused function warning despite being a template specialization.
+template <typename T>
+inline void CreateDataDescForPayload(PayloadBuffer& aBuffer,
+                                     EVENT_DATA_DESCRIPTOR& aDescriptor,
+                                     const nsTString<T>& aPayload) {
+  EventDataDescCreate(&aDescriptor, aPayload.BeginReading(),
+                      (aPayload.Length() + 1) * sizeof(T));
+}
+template <typename T>
+inline void CreateDataDescForPayload(PayloadBuffer& aBuffer,
+                                     EVENT_DATA_DESCRIPTOR& aDescriptor,
+                                     const nsTSubstring<T>& aPayload) {
+  EventDataDescCreate(&aDescriptor, aPayload.BeginReading(),
+                      (aPayload.Length() + 1) * sizeof(T));
+}
+
+// Template specialization that writes out empty data descriptors for an empty
+// Maybe<T>
+template <typename T>
+void CreateDataDescForPayload(PayloadBuffer& aBuffer,
+                              EVENT_DATA_DESCRIPTOR& aDescriptor,
+                              const mozilla::Maybe<T>& aPayload) {
+  if (aPayload.isNothing()) {
+    EventDataDescCreate(&aDescriptor, nullptr, 0);
+  } else {
+    CreateDataDescForPayload(aBuffer, aDescriptor, *aPayload);
+  }
+}
+
+template <typename T, typename = void>
+struct MarkerSupportsETW : std::false_type {};
+template <typename T>
+struct MarkerSupportsETW<T, std::void_t<decltype(T::PayloadFields)>>
+    : std::true_type {};
+
+template <typename T, typename = void>
+struct MarkerHasTranslator : std::false_type {};
+template <typename T>
+struct MarkerHasTranslator<
+    T, std::void_t<decltype(T::TranslateMarkerInputToSchema)>>
+    : std::true_type {};
+
+struct BaseEventStorage {
+  uint64_t mStartTime;
+  uint64_t mEndTime;
+  uint64_t mWindowID;
+  uint32_t mCategoryPair;
+};
+
+static inline void StoreBaseEventDataDesc(
+    BaseEventStorage& aStorage, EVENT_DATA_DESCRIPTOR* aDescriptors,
+    const mozilla::MarkerCategory& aCategory,
+    const mozilla::MarkerOptions& aOptions) {
+  if (!aOptions.IsTimingUnspecified()) {
+    aStorage.mStartTime =
+        aOptions.Timing().StartTime().RawQueryPerformanceCounterValue().value();
+    aStorage.mEndTime =
+        aOptions.Timing().EndTime().RawQueryPerformanceCounterValue().value();
+  }
+  if (!aOptions.InnerWindowId().IsUnspecified()) {
+    aStorage.mWindowID = aOptions.InnerWindowId().Id();
+  }
+  aStorage.mCategoryPair = uint32_t(aCategory.CategoryPair());
+  EventDataDescCreate(&aDescriptors[2], &aStorage.mStartTime, sizeof(uint64_t));
+  EventDataDescCreate(&aDescriptors[3], &aStorage.mEndTime, sizeof(uint64_t));
+  EventDataDescCreate(&aDescriptors[4], &aStorage.mWindowID, sizeof(uint64_t));
+  EventDataDescCreate(&aDescriptors[5], &aStorage.mCategoryPair,
+                      sizeof(uint32_t));
+}
+
+// This is used for markers with no explicit type or markers which have not
+// been converted to the updated schema yet.
+static inline void EmitETWMarker(const mozilla::ProfilerString8View& aName,
+                                 const mozilla::MarkerCategory& aCategory,
+                                 const mozilla::MarkerOptions& aOptions = {}) {
+  if (!(gETWCollectionMask &
+        uint64_t(mozilla::MarkerSchema::ETWMarkerGroup::Generic))) {
+    return;
+  }
+
+  static const __declspec(allocate(_tlgSegMetadataEvents)) __declspec(
+      align(1)) constexpr StaticMetaData<SimpleMarkerType>
+      staticData;
+
+  std::array<EVENT_DATA_DESCRIPTOR, 7> descriptors = {};
+
+  // This is storage space allocated on the stack for POD values.
+  BaseEventStorage dataStorage = {};
+
+  StoreBaseEventDataDesc(dataStorage, descriptors.data(), aCategory,
+                         std::move(aOptions));
+
+  EventDataDescCreate(&descriptors[6], aName.StringView().data(),
+                      aName.StringView().size() + 1);
+  _tlgWriteTransfer(kFirefoxTraceLoggingProvider, &staticData.metaData.Channel,
+                    NULL, NULL, descriptors.size(), descriptors.data());
+}
+
+template <typename MarkerType, typename... PayloadArguments>
+static inline void EmitETWMarker(const mozilla::ProfilerString8View& aName,
+                                 const mozilla::MarkerCategory& aCategory,
+                                 const mozilla::MarkerOptions& aOptions,
+                                 MarkerType aMarkerType,
+                                 const PayloadArguments&... aPayloadArguments) {
+  // If our MarkerType has not been made to support ETW, emit only the base
+  // event. Avoid attempting to compile the rest of the function.
+  if constexpr (!MarkerSupportsETW<MarkerType>::value) {
+    return EmitETWMarker(aName, aCategory, aOptions);
+  } else {
+    if (!(gETWCollectionMask & uint64_t(MarkerType::Group))) {
+      return;
+    }
+
+    static const __declspec(allocate(_tlgSegMetadataEvents)) __declspec(
+        align(1)) constexpr StaticMetaData<MarkerType>
+        staticData;
+
+    // Allocate the exact amount of descriptors required by this event.
+    std::array<EVENT_DATA_DESCRIPTOR,
+               2 + std::size(MarkerType::PayloadFields) +
+                   std::size(BaseMarkerDescription::PayloadFields)>
+        descriptors = {};
+
+    // Memory allocated on the stack for storing intermediate values.
+    BaseEventStorage dataStorage = {};
+    PayloadBuffer buffer;
+
+    StoreBaseEventDataDesc(dataStorage, descriptors.data(), aCategory,
+                           aOptions);
+
+    if constexpr (MarkerHasTranslator<MarkerType>::value) {
+      // When this function is implemented the arguments are passed back to the
+      // MarkerType object which is expected to call OutputMarkerSchema with
+      // the correct argument format.
+      buffer.mDescriptors = descriptors.data() + 2 +
+                            std::size(BaseMarkerDescription::PayloadFields);
+      MarkerType::TranslateMarkerInputToSchema(&buffer, aPayloadArguments...);
+    } else {
+      const size_t argCount = sizeof...(PayloadArguments);
+      static_assert(
+          argCount == std::size(MarkerType::PayloadFields),
+          "Number and type of fields must be equal to number and type of "
+          "payload arguments. If this is not the case a "
+          "TranslateMarkerInputToSchema function must be defined.");
+      size_t i = 2 + std::size(BaseMarkerDescription::PayloadFields);
+      (CreateDataDescForPayload(buffer, descriptors[i++], aPayloadArguments),
+       ...);
+    }
+
+    _tlgWriteTransfer(kFirefoxTraceLoggingProvider,
+                      &staticData.metaData.Channel, NULL, NULL,
+                      descriptors.size(), descriptors.data());
+  }
+}
+
+// This function allows markers to specify a translator function for when
+// their arguments to profiler_add_marker do not exactly match the schema or
+// when they need to make other adjustments to the data.
+template <typename MarkerType, typename... PayloadArguments>
+void OutputMarkerSchema(void* aContext, MarkerType aMarkerType,
+                        const PayloadArguments&... aPayloadArguments) {
+  const size_t argCount = sizeof...(PayloadArguments);
+  static_assert(argCount == std::size(MarkerType::PayloadFields),
+                "Number and type of fields must be equal to number and type of "
+                "payload arguments.");
+
+  PayloadBuffer* buffer = static_cast<PayloadBuffer*>(aContext);
+  size_t i = 0;
+  (CreateDataDescForPayload(*buffer, buffer->mDescriptors[i++],
+                            aPayloadArguments),
+   ...);
+}
+}  // namespace ETW
+
+#else
+namespace ETW {
+static inline void Init() {}
+static inline void Shutdown() {}
+static inline void EmitETWMarker(const mozilla::ProfilerString8View& aName,
+                                 const mozilla::MarkerCategory& aCategory,
+                                 const mozilla::MarkerOptions& aOptions = {}) {}
+template <typename MarkerType, typename... PayloadArguments>
+static inline void EmitETWMarker(const mozilla::ProfilerString8View& aName,
+                                 const mozilla::MarkerCategory& aCategory,
+                                 const mozilla::MarkerOptions& aOptions,
+                                 MarkerType aMarkerType,
+                                 const PayloadArguments&... aPayloadArguments) {
+}
+template <typename MarkerType, typename... PayloadArguments>
+void OutputMarkerSchema(void* aContext, MarkerType aMarkerType,
+                        const PayloadArguments&... aPayloadArguments) {}
+}  // namespace ETW
+#endif
+
+#endif  // ETWTools_h