[browser] single threaded diagnostic server

src/coreclr/nativeaot/Runtime/eventpipe/ep-rt-aot.h

@@ -512,6 +512,26 @@ ep_rt_sample_profiler_write_sampling_event_for_threads (
     ep_rt_aot_sample_profiler_write_sampling_event_for_threads (sampling_thread, sampling_event);
 }
 
+static
+inline
+void
+ep_rt_sample_profiler_enabled (void)
+{
+    STATIC_CONTRACT_NOTHROW;
+
+    // no-op
+}
+
+static
+inline
+void
+ep_rt_sample_profiler_disabled (void)
+{
+    STATIC_CONTRACT_NOTHROW;
+
+    // no-op
+}
+
 static
 inline
 void

src/coreclr/vm/eventing/eventpipe/ep-rt-coreclr.h

@@ -567,6 +567,26 @@ ep_rt_sample_profiler_write_sampling_event_for_threads (
 	ep_rt_coreclr_sample_profiler_write_sampling_event_for_threads (sampling_thread, sampling_event);
 }
 
+static
+inline
+void
+ep_rt_sample_profiler_enabled (void)
+{
+    STATIC_CONTRACT_NOTHROW;
+
+    // no-op
+}
+
+static
+inline
+void
+ep_rt_sample_profiler_disabled (void)
+{
+    STATIC_CONTRACT_NOTHROW;
+
+    // no-op
+}
+
 static
 inline
 void

src/mono/System.Private.CoreLib/System.Private.CoreLib.csproj

@@ -114,7 +114,7 @@
     <FeatureSingleThread Condition="('$(TargetsBrowser)' == 'true' or '$(TargetsWasi)' == 'true') and '$(WasmEnableThreads)' != 'true'">true</FeatureSingleThread>
     <FeaturePortableTimer Condition="('$(TargetsBrowser)' != 'true' and '$(TargetsWasi)' != 'true') or '$(FeatureWasmManagedThreads)' == 'true'">true</FeaturePortableTimer>
     <FeaturePortableThreadPool Condition="('$(TargetsBrowser)' != 'true' and '$(TargetsWasi)' != 'true') or '$(FeatureWasmManagedThreads)' == 'true'">true</FeaturePortableThreadPool>
-    <FeaturePerfTracing Condition="('$(TargetsBrowser)' != 'true' and '$(TargetsWasi)' != 'true')">true</FeaturePerfTracing>
+    <FeaturePerfTracing Condition="('$(TargetsWasi)' != 'true')">true</FeaturePerfTracing>
     <FeatureObjCMarshal Condition="'$(TargetsOSX)' == 'true' or '$(TargetsMacCatalyst)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true'">true</FeatureObjCMarshal>
   </PropertyGroup>
 
@@ -135,7 +135,7 @@
     <ILLinkDescriptorsXmls Include="$(ILLinkDirectory)ILLink.Descriptors.xml" />
     <ILLinkDescriptorsXmls Include="$(ILLinkDirectory)ILLink.Descriptors.OSX.xml" Condition="'$(TargetsOSX)' == 'true' or '$(TargetsMacCatalyst)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true'" />
     <ILLinkDescriptorsXmls Include="$(CoreLibSharedDir)ILLink\ILLink.Descriptors.Shared.xml" />
-    <ILLinkDescriptorsXmls Condition="'$(FeaturePerfTracing)' == 'true'" Include="$(CoreLibSharedDir)ILLink\ILLink.Descriptors.EventSource.xml" />
+    <ILLinkDescriptorsLibraryBuildXml Condition="'$(FeaturePerfTracing)' == 'true'" Include="$(CoreLibSharedDir)ILLink\ILLink.Descriptors.EventSource.xml" />
 
     <ILLinkSubstitutionsXmls Include="$(ILLinkDirectory)ILLink.Substitutions.$(Platform).xml" Condition="Exists('$(ILLinkDirectory)ILLink.Substitutions.$(Platform).xml')" />
     <ILLinkSubstitutionsXmls Include="$(ILLinkDirectory)ILLink.Substitutions.iOS.xml" Condition="'$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true'" />

src/mono/browser/browser.proj

@@ -424,6 +424,8 @@
       <_CmakeEnvironmentVariable Include="ENABLE_JS_INTEROP_BY_VALUE=0" Condition="'$(WasmEnableJsInteropByValue)' == 'false'"/>
       <_CmakeEnvironmentVariable Include="WASM_ENABLE_SIMD=1" Condition="'$(WasmEnableSIMD)' != 'false'" />
       <_CmakeEnvironmentVariable Include="WASM_ENABLE_SIMD=0" Condition="'$(WasmEnableSIMD)' == 'false'" />
+      <_CmakeEnvironmentVariable Include="FEATURE_PERFTRACING=1" Condition="'$(FeaturePerfTracing)' != 'false'" />
+      <_CmakeEnvironmentVariable Include="FEATURE_PERFTRACING=0" Condition="'$(FeaturePerfTracing)' == 'false'" />
       <_CmakeEnvironmentVariable Include="WASM_ENABLE_EH=1" Condition="'$(WasmEnableExceptionHandling)' != 'false'" />
       <_CmakeEnvironmentVariable Include="WASM_ENABLE_EH=0" Condition="'$(WasmEnableExceptionHandling)' == 'false'" />
       <_CmakeEnvironmentVariable Include="RUN_AOT_COMPILATION=1" Condition="'$(RunAOTCompilation)' == 'true'" />
@@ -568,6 +570,8 @@
       <_MonoRollupEnvironmentVariable Include="WasmEnableThreads:$(WasmEnableThreads)" />
       <_MonoRollupEnvironmentVariable Include="WASM_ENABLE_SIMD:1" Condition="'$(WasmEnableSIMD)' != 'false'" />
       <_MonoRollupEnvironmentVariable Include="WASM_ENABLE_SIMD:0" Condition="'$(WasmEnableSIMD)' == 'false'" />
+      <_MonoRollupEnvironmentVariable Include="FEATURE_PERFTRACING:1" Condition="'$(FeaturePerfTracing)' != 'false'" />
+      <_MonoRollupEnvironmentVariable Include="FEATURE_PERFTRACING:0" Condition="'$(FeaturePerfTracing)' == 'false'" />
       <_MonoRollupEnvironmentVariable Include="WASM_ENABLE_EH:1" Condition="'$(WasmEnableExceptionHandling)' != 'false'" />
       <_MonoRollupEnvironmentVariable Include="WASM_ENABLE_EH:0" Condition="'$(WasmEnableExceptionHandling)' == 'false'" />
       <_MonoRollupEnvironmentVariable Include="ENABLE_JS_INTEROP_BY_VALUE:1" Condition="'$(WasmEnableJsInteropByValue)' == 'true'" />

src/mono/browser/build/BrowserWasmApp.targets

@@ -3,6 +3,8 @@
     <!-- Post Wasm MVP features -->
     <WasmEnableExceptionHandling Condition="'$(WasmEnableExceptionHandling)' == ''">true</WasmEnableExceptionHandling>
     <WasmEnableSIMD Condition="'$(WasmEnableSIMD)' == ''">$(WasmEnableExceptionHandling)</WasmEnableSIMD>
+    <FeaturePerfTracing Condition="'$(FeaturePerfTracing)' == '' and '$(Configuration)' == 'Debug'">true</FeaturePerfTracing>
+    <FeaturePerfTracing Condition="'$(FeaturePerfTracing)' == ''">false</FeaturePerfTracing>
   </PropertyGroup>
 
   <Import Project="$(WasmCommonTargetsPath)WasmApp.Common.targets" />
@@ -362,6 +364,8 @@
       <EmscriptenEnvVars Include="ENABLE_JS_INTEROP_BY_VALUE=0" Condition="'$(WasmEnableJsInteropByValue)' != 'true'" />
       <EmscriptenEnvVars Include="WASM_ENABLE_SIMD=1" Condition="'$(WasmEnableSIMD)' != 'false'" />
       <EmscriptenEnvVars Include="WASM_ENABLE_SIMD=0" Condition="'$(WasmEnableSIMD)' == 'false'" />
+      <EmscriptenEnvVars Include="FEATURE_PERFTRACING=1" Condition="'$(FeaturePerfTracing)' != 'false'" />
+      <EmscriptenEnvVars Include="FEATURE_PERFTRACING=0" Condition="'$(FeaturePerfTracing)' == 'false'" />
       <EmscriptenEnvVars Include="WASM_ENABLE_EH=1" Condition="'$(WasmEnableExceptionHandling)' != 'false'" />
       <EmscriptenEnvVars Include="WASM_ENABLE_EH=0" Condition="'$(WasmEnableExceptionHandling)' == 'false'" />
       <EmscriptenEnvVars Include="ENABLE_AOT_PROFILER=$([System.Convert]::ToInt32($(WasmProfilers.Contains('aot'))))" />

src/mono/browser/build/WasmApp.InTree.props

@@ -28,7 +28,7 @@
   <!-- This is temporary hack for https://github.com/dotnet/runtime/issues/61294 -->
   <ItemGroup>
     <_MonoRuntimeComponentDontLink Include="libmono-component-debugger-stub-static.a" />
-    <_MonoRuntimeComponentDontLink Include="libmono-component-diagnostics_tracing-static.a"/>
+    <_MonoRuntimeComponentDontLink Include="libmono-component-diagnostics_tracing-stub-static.a" />
     <_MonoRuntimeComponentDontLink Include="libmono-component-hot_reload-stub-static.a" />
     <_MonoRuntimeComponentDontLink Include="libmono-component-marshal-ilgen-stub-static.a" />
   </ItemGroup>

src/mono/browser/runtime/corebindings.c

@@ -32,6 +32,7 @@ extern void mono_wasm_invoke_js_function (int function_js_handle, void *args);
 extern int mono_runtime_run_module_cctor (MonoImage *image, MonoError *error);
 
 typedef void (*background_job_cb)(void);
+typedef int (*ds_job_cb)(void* data);
 
 void mono_wasm_bind_assembly_exports (char *assembly_name);
 void mono_wasm_assembly_get_entry_point (char *assembly_name, int auto_insert_breakpoint, MonoMethod **method_out);

src/mono/browser/runtime/cwraps.ts

@@ -42,6 +42,7 @@ const fn_signatures: SigLine[] = [
     [true, "mono_wasm_parse_runtime_options", null, ["number", "number"]],
     [true, "mono_wasm_strdup", "number", ["string"]],
     [true, "mono_background_exec", null, []],
+    [true, "mono_wasm_ds_exec", null, []],
     [true, "mono_wasm_execute_timer", null, []],
     [true, "mono_wasm_load_icu_data", "number", ["number"]],
     [false, "mono_wasm_add_assembly", "number", ["string", "number", "number"]],
@@ -166,6 +167,7 @@ export interface t_Cwraps {
     mono_wasm_strdup(value: string): number;
     mono_wasm_parse_runtime_options(length: number, argv: VoidPtr): void;
     mono_background_exec(): void;
+    mono_wasm_ds_exec(): void;
     mono_wasm_execute_timer(): void;
     mono_wasm_load_icu_data(offset: VoidPtr): number;
     mono_wasm_add_assembly(name: string, data: VoidPtr, size: number): number;

src/mono/browser/runtime/es6/dotnet.es6.lib.js

@@ -8,6 +8,7 @@
 
 // because we can't pass custom define symbols to acorn optimizer, we use environment variables to pass other build options
 const WASM_ENABLE_SIMD = process.env.WASM_ENABLE_SIMD === "1";
+const FEATURE_PERFTRACING = process.env.FEATURE_PERFTRACING === "1";
 const WASM_ENABLE_EH = process.env.WASM_ENABLE_EH === "1";
 const ENABLE_BROWSER_PROFILER = process.env.ENABLE_BROWSER_PROFILER === "1";
 const ENABLE_AOT_PROFILER = process.env.ENABLE_AOT_PROFILER === "1";
@@ -86,6 +87,7 @@ function injectDependencies() {
     DotnetSupportLib["$DOTNET__postset"] = `DOTNET.setup({ ` +
         `wasmEnableSIMD: ${WASM_ENABLE_SIMD ? "true" : "false"},` +
         `wasmEnableEH: ${WASM_ENABLE_EH ? "true" : "false"},` +
+        `enablePerfTracing: ${FEATURE_PERFTRACING ? "true" : "false"}, ` +
         `enableAotProfiler: ${ENABLE_AOT_PROFILER ? "true" : "false"}, ` +
         `enableBrowserProfiler: ${ENABLE_BROWSER_PROFILER ? "true" : "false"}, ` +
         `enableLogProfiler: ${ENABLE_LOG_PROFILER ? "true" : "false"}, ` +

src/mono/browser/runtime/exports-binding.ts

@@ -13,7 +13,7 @@ import { mono_wasm_resolve_or_reject_promise } from "./marshal-to-js";
 import { mono_wasm_schedule_timer, schedule_background_exec } from "./scheduling";
 import { mono_wasm_asm_loaded } from "./startup";
 import { mono_log_warn, mono_wasm_console_clear, mono_wasm_trace_logger } from "./logging";
-import { mono_wasm_profiler_leave, mono_wasm_profiler_enter } from "./profiler";
+import { mono_wasm_profiler_leave, mono_wasm_profiler_enter, ds_rt_websocket_close, ds_rt_websocket_create, ds_rt_websocket_poll, ds_rt_websocket_recv, ds_rt_websocket_send } from "./profiler";
 import { mono_wasm_browser_entropy } from "./crypto";
 import { mono_wasm_cancel_promise } from "./cancelable-promise";
 
@@ -88,6 +88,13 @@ export const mono_wasm_imports = [
     mono_wasm_invoke_jsimport_ST,
     mono_wasm_resolve_or_reject_promise,
     mono_wasm_cancel_promise,
+
+    //event pipe
+    ds_rt_websocket_create,
+    ds_rt_websocket_send,
+    ds_rt_websocket_poll,
+    ds_rt_websocket_recv,
+    ds_rt_websocket_close,
 ];
 
 

src/mono/browser/runtime/profiler.ts

@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+import type { CharPtr, VoidPtr } from "./types/emscripten";
+
 import { ENVIRONMENT_IS_WEB, mono_assert, runtimeHelpers } from "./globals";
 import { MonoMethod, AOTProfilerOptions, BrowserProfilerOptions, LogProfilerOptions } from "./types/internal";
 import { profiler_c_functions as cwraps } from "./cwraps";
@@ -105,3 +107,24 @@ export function mono_wasm_profiler_leave (method: MonoMethod): void {
         globalThis.performance.measure(methodName, options);
     }
 }
+
+/* eslint-disable @typescript-eslint/no-unused-vars */
+export function ds_rt_websocket_create (urlPtr :CharPtr):number {
+    throw new Error("TODO");
+}
+
+export function ds_rt_websocket_send (client_socket :number, buffer:VoidPtr, bytes_to_write:number):number {
+    throw new Error("TODO");
+}
+
+export function ds_rt_websocket_poll (client_socket :number):number {
+    throw new Error("TODO");
+}
+
+export function ds_rt_websocket_recv (client_socket :number, buffer:VoidPtr, bytes_to_read:number):number {
+    throw new Error("TODO");
+}
+
+export function ds_rt_websocket_close (client_socket :number):number {
+    throw new Error("TODO");
+}

src/mono/browser/runtime/rollup.config.js

@@ -20,6 +20,7 @@ const nativeBinDir = process.env.NativeBinDir ? process.env.NativeBinDir.replace
 const wasmObjDir = process.env.WasmObjDir ? process.env.WasmObjDir.replace(/"/g, "") : "obj";
 const wasmEnableThreads = process.env.WasmEnableThreads === "true" ? true : false;
 const wasmEnableSIMD = process.env.WASM_ENABLE_SIMD === "1" ? true : false;
+const wasmEnablePerfTracing = process.env.FEATURE_PERFTRACING === "1" ? true : false;
 const wasmEnableExceptionHandling = process.env.WASM_ENABLE_EH === "1" ? true : false;
 const wasmEnableJsInteropByValue = process.env.ENABLE_JS_INTEROP_BY_VALUE == "1" ? true : false;
 // because of stack walk at src/mono/browser/debugger/BrowserDebugProxy/MonoProxy.cs
@@ -108,6 +109,7 @@ const envConstants = {
     configuration,
     wasmEnableThreads,
     wasmEnableSIMD,
+    wasmEnablePerfTracing,
     wasmEnableExceptionHandling,
     gitHash,
     wasmEnableJsInteropByValue,

src/mono/browser/runtime/types/internal.ts

@@ -283,6 +283,7 @@ export type EmscriptenBuildOptions = {
     enableAotProfiler: boolean,
     enableBrowserProfiler: boolean,
     enableLogProfiler: boolean,
+    enablePerfTracing: boolean,
     runAOTCompilation: boolean,
     wasmEnableThreads: boolean,
     gitHash: string,

src/mono/mono.proj

@@ -698,12 +698,18 @@ JS_ENGINES = [NODE_JS]
       <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_DISABLE_DEFAULT_LISTEN_PORT=1"/>
     </ItemGroup>
 
-    <ItemGroup Condition="'$(TargetsBrowser)' == 'true' or '$(TargetsWasi)' == 'true'">
+    <ItemGroup Condition="'$(TargetsWasi)' == 'true'">
       <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_DISABLE_PERFTRACING_LISTEN_PORTS=1"/>
       <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_DISABLE_DEFAULT_LISTEN_PORT=1"/>
       <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_DISABLE_CONNECT_PORTS=1" />
     </ItemGroup>
 
+    <ItemGroup Condition="'$(TargetsBrowser)' == 'true'">
+      <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_PAL_WS=1"/>
+      <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_DISABLE_PERFTRACING_LISTEN_PORTS=1"/>
+      <_MonoCMakeArgs Include="-DFEATURE_PERFTRACING_DISABLE_DEFAULT_LISTEN_PORT=1"/>
+    </ItemGroup>
+
     <!-- Components -->
     <ItemGroup Condition="'$(MonoComponentsStatic)' == 'true'">
       <_MonoCMakeArgs Include="-DSTATIC_COMPONENTS=1" />

src/mono/mono/component/CMakeLists.txt

@@ -216,6 +216,15 @@ endif()
 if (ENABLE_PERFTRACING AND "${MONO_DIAGNOSTICS_TRACING_COMPONENT_NAME}" IN_LIST components_to_build)
     # Build EventPipe and DiagnosticServer with the Mono runtime implementation as unity-builds.
     add_library(eventpipe-mono-objects OBJECT)
+
+    if (DISABLE_THREADS)
+        set_target_properties(
+            eventpipe-mono-objects
+            PROPERTIES
+            DISABLE_THREADS ON
+        )
+    endif()
+
     set_target_properties(
         eventpipe-mono-objects
         PROPERTIES

src/mono/mono/eventpipe/ep-rt-mono-runtime-provider.c

@@ -25,8 +25,14 @@ extern EVENTPIPE_TRACE_CONTEXT MICROSOFT_WINDOWS_DOTNETRUNTIME_RUNDOWN_PROVIDER_
 #define NUM_NANOSECONDS_IN_1_MS 1000000
 
 // Sample profiler.
+#if defined(PERFTRACING_MULTI_THREADED)
 static GArray * _sampled_thread_callstacks = NULL;
 static uint32_t _max_sampled_thread_count = 32;
+#else
+MonoProfilerHandle _ep_rt_mono_sampling_profiler_provider;
+static EventPipeEvent *current_sampling_event = NULL;
+static ep_rt_thread_handle_t current_sampling_thread = NULL;
+#endif
 
 // Mono profilers.
 extern MonoProfilerHandle _ep_rt_mono_default_profiler_provider;
@@ -1207,6 +1213,7 @@ ep_rt_mono_walk_managed_stack_for_thread (
 	return true;
 }
 
+#if defined(PERFTRACING_MULTI_THREADED)
 bool
 ep_rt_mono_sample_profiler_write_sampling_event_for_threads (
 	ep_rt_thread_handle_t sampling_thread,
@@ -1306,6 +1313,94 @@ ep_rt_mono_sample_profiler_write_sampling_event_for_threads (
 	return true;
 }
 
+#else // !PERFTRACING_MULTI_THREADED
+
+bool
+ep_rt_mono_sample_profiler_write_sampling_event_for_threads (
+	ep_rt_thread_handle_t sampling_thread,
+	EventPipeEvent *sampling_event)
+{
+	// here we just store the context for later
+	current_sampling_event = sampling_event;
+	current_sampling_thread = sampling_thread;
+
+	return true;
+}
+
+static void
+method_enter (MonoProfiler *prof, MonoMethod *method, MonoProfilerCallContext *ctx)
+{
+	MonoThreadInfo *thread_info = mono_thread_info_current ();
+	SampleProfileStackWalkData stack_walk_data;
+	SampleProfileStackWalkData *data= &stack_walk_data;
+	THREAD_INFO_TYPE adapter = { { 0 } };
+
+	data->thread_id = ep_rt_thread_id_t_to_uint64_t (mono_thread_info_get_tid (thread_info));
+	data->thread_ip = (uintptr_t)MONO_CONTEXT_GET_IP (&ctx->context);
+	data->payload_data = EP_SAMPLE_PROFILER_SAMPLE_TYPE_ERROR;
+	data->stack_walk_data.stack_contents = &data->stack_contents;
+	data->stack_walk_data.top_frame = true;
+	data->stack_walk_data.async_frame = false;
+	data->stack_walk_data.safe_point_frame = false;
+	data->stack_walk_data.runtime_invoke_frame = false;
+	ep_stack_contents_reset (&data->stack_contents);
+
+	mono_get_eh_callbacks ()->mono_walk_stack_with_ctx (sample_profiler_walk_managed_stack_for_thread_callback, &ctx->context, MONO_UNWIND_SIGNAL_SAFE, &stack_walk_data);
+	if (data->payload_data == EP_SAMPLE_PROFILER_SAMPLE_TYPE_EXTERNAL && (data->stack_walk_data.safe_point_frame || data->stack_walk_data.runtime_invoke_frame)) {
+		data->payload_data = EP_SAMPLE_PROFILER_SAMPLE_TYPE_MANAGED;
+	}
+	if (data->stack_walk_data.top_frame && ep_stack_contents_get_length (&data->stack_contents) == 0) {
+		data->payload_data = EP_SAMPLE_PROFILER_SAMPLE_TYPE_EXTERNAL;
+	}
+
+	if ((data->stack_walk_data.top_frame && data->payload_data == EP_SAMPLE_PROFILER_SAMPLE_TYPE_EXTERNAL) || (data->payload_data != EP_SAMPLE_PROFILER_SAMPLE_TYPE_ERROR && ep_stack_contents_get_length (&data->stack_contents) > 0)) {
+		if (data->stack_walk_data.async_frame) {
+			for (uint32_t frame_count = 0; frame_count < data->stack_contents.next_available_frame; ++frame_count)
+				mono_jit_info_table_find_internal ((gpointer)data->stack_contents.stack_frames [frame_count], TRUE, FALSE);
+		}
+		mono_thread_info_set_tid (&adapter, ep_rt_uint64_t_to_thread_id_t (data->thread_id));
+		uint32_t payload_data = ep_rt_val_uint32_t (data->payload_data);
+		ep_write_sample_profile_event (current_sampling_thread, current_sampling_event, &adapter, &data->stack_contents, (uint8_t *)&payload_data, sizeof (payload_data));
+	}
+}
+
+static MonoProfilerCallInstrumentationFlags
+method_filter (MonoProfiler *prof, MonoMethod *method)
+{
+	// TODO add more instrumentation, something like MINT_SDB_SEQ_POINT
+	return MONO_PROFILER_CALL_INSTRUMENTATION_ENTER;
+}
+
+#endif // PERFTRACING_MULTI_THREADED
+
+void
+ep_rt_mono_sampling_provider_component_init (void)
+{
+#if defined(PERFTRACING_SINGLE_THREADED)
+	// in single-threaded mode, we install instrumentation callbacks on the mono profiler, instead of stop-the-world
+	_ep_rt_mono_sampling_profiler_provider = mono_profiler_create (NULL);
+	// this has negative performance impact even when the EP client is not connected!
+	// but it has to be enabled before managed code starts running, because the instrumentation needs to be in place
+	mono_profiler_set_call_instrumentation_filter_callback (_ep_rt_mono_sampling_profiler_provider, method_filter);
+#endif
+}
+
+void
+ep_rt_mono_sample_profiler_enabled (void)
+{
+#if defined(PERFTRACING_SINGLE_THREADED)
+	mono_profiler_set_method_enter_callback (_ep_rt_mono_sampling_profiler_provider, method_enter);
+#endif
+}
+
+void
+ep_rt_mono_sample_profiler_disabled (void)
+{
+#if defined(PERFTRACING_SINGLE_THREADED)
+	mono_profiler_set_method_enter_callback (_ep_rt_mono_sampling_profiler_provider, NULL);
+#endif
+}
+
 void
 ep_rt_mono_execute_rundown (dn_vector_ptr_t *execution_checkpoints)
 {

src/mono/mono/eventpipe/ep-rt-mono.c

@@ -789,6 +789,7 @@ ep_rt_mono_component_init (void)
 	g_free (diag_env);
 
 	ep_rt_mono_runtime_provider_component_init ();
+	ep_rt_mono_sampling_provider_component_init ();
 	ep_rt_mono_profiler_provider_component_init ();
 }