Add configurable EventPipe CPU sampling rate via DOTNET_EventPipeThreadSamplingRate

src/coreclr/inc/clrconfigvalues.h

@@ -610,6 +610,7 @@ RETAIL_CONFIG_DWORD_INFO(INTERNAL_EventPipeCircularMB, W("EventPipeCircularMB"),
 RETAIL_CONFIG_DWORD_INFO(INTERNAL_EventPipeProcNumbers, W("EventPipeProcNumbers"), 0, "Enable/disable capturing processor numbers in EventPipe event headers")
 RETAIL_CONFIG_DWORD_INFO(INTERNAL_EventPipeOutputStreaming, W("EventPipeOutputStreaming"), 1, "Enable/disable streaming for trace file set in DOTNET_EventPipeOutputPath.  Non-zero values enable streaming.")
 RETAIL_CONFIG_DWORD_INFO(INTERNAL_EventPipeEnableStackwalk, W("EventPipeEnableStackwalk"), 1, "Set to 0 to disable collecting stacks for EventPipe events.")
+RETAIL_CONFIG_DWORD_INFO(INTERNAL_EventPipeThreadSamplingRate, W("EventPipeThreadSamplingRate"), 0, "Desired sample interval in milliseconds for EventPipe thread time sampling profiler. 0 means use the default.")
 
 #ifdef FEATURE_AUTO_TRACE
 RETAIL_CONFIG_DWORD_INFO_EX(INTERNAL_AutoTrace_N_Tracers, W("AutoTrace_N_Tracers"), 0, "", CLRConfig::LookupOptions::ParseIntegerAsBase10)

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

@@ -507,6 +507,23 @@ ep_rt_config_value_get_enable_stackwalk (void)
     return false;
 }
 
+static
+inline
+uint32_t
+ep_rt_config_value_get_sampling_rate (void)
+{
+    STATIC_CONTRACT_NOTHROW;
+
+    uint64_t value;
+    if (RhConfig::Environment::TryGetIntegerValue("EventPipeThreadSamplingRate", &value, true))
+    {
+        EP_ASSERT(value <= UINT32_MAX);
+        return static_cast<uint32_t>(value);
+    }
+
+    return 0;
+}
+
 /*
  * EventPipeSampleProfiler.
  */

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

@@ -444,9 +444,9 @@ ep_rt_provider_config_init (EventPipeProviderConfiguration *provider_config)
 // This function is auto-generated from /src/scripts/genEventPipe.py
 #ifdef TARGET_UNIX
 extern "C" void InitProvidersAndEvents ();
-#else
+#else // TARGET_UNIX
 extern void InitProvidersAndEvents ();
-#endif
+#endif // TARGET_UNIX
 
 static
 void
@@ -572,6 +572,15 @@ ep_rt_config_value_get_enable_stackwalk (void)
 	return CLRConfig::GetConfigValue(CLRConfig::INTERNAL_EventPipeEnableStackwalk) != 0;
 }
 
+static
+inline
+uint32_t
+ep_rt_config_value_get_sampling_rate (void)
+{
+	STATIC_CONTRACT_NOTHROW;
+	return CLRConfig::GetConfigValue(CLRConfig::INTERNAL_EventPipeThreadSamplingRate);
+}
+
 /*
  * EventPipeSampleProfiler.
  */
@@ -622,13 +631,12 @@ void
 ep_rt_notify_profiler_provider_created (EventPipeProvider *provider)
 {
 	STATIC_CONTRACT_NOTHROW;
-
-#ifndef DACCESS_COMPILE
+#if !defined(DACCESS_COMPILE) && defined(PROFILING_SUPPORTED)
 		// Let the profiler know the provider has been created so it can register if it wants to
 		BEGIN_PROFILER_CALLBACK (CORProfilerTrackEventPipe ());
 		(&g_profControlBlock)->EventPipeProviderCreated (provider);
 		END_PROFILER_CALLBACK ();
-#endif // DACCESS_COMPILE
+#endif // !DACCESS_COMPILE && PROFILING_SUPPORTED
 }
 
 /*

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

@@ -14,10 +14,14 @@
   <Import Sdk="Microsoft.NET.Sdk.WebAssembly" Project="Sdk.props" Condition="'$(UsingNativeAOT)' != 'true' and '$(UsingMicrosoftNETSdkWebAssembly)' == 'true'" />
   <Import Project="$(MSBuildThisFileDirectory)BrowserWasmApp.props" Condition="'$(UsingNativeAOT)' != 'true' and '$(RuntimeFlavor)' == 'Mono'" />
 
-  <!-- TODO-WASM https://github.com/dotnet/runtime/issues/120226 (CoreCLR on wasm defaults) -->
   <PropertyGroup Condition="'$(RuntimeFlavor)' == 'CoreCLR'">
+    <UseMonoRuntime>false</UseMonoRuntime>
+    <!-- TODO-WASM https://github.com/dotnet/runtime/issues/120226 (CoreCLR on wasm defaults) -->
     <InvariantGlobalization Condition="'$(InvariantGlobalization)' == ''">false</InvariantGlobalization>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(RuntimeFlavor)' == 'Mono'">
+    <UseMonoRuntime>true</UseMonoRuntime>
+  </PropertyGroup>
 
   <PropertyGroup Condition="'$(IsTestProject)' == 'true' or '$(IsOutputTypeLibrary)' == 'true'">
     <OutputType>library</OutputType>

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

@@ -1507,8 +1507,6 @@ void
 ep_rt_mono_sample_profiler_enabled (EventPipeEvent *sampling_event)
 {
 	desired_sample_interval_ms = ((double)ep_sample_profiler_get_sampling_rate ()) / 1000000.0;
-	EP_ASSERT (desired_sample_interval_ms >= 0.0);
-	EP_ASSERT (desired_sample_interval_ms < 1000.0);
 
 	current_sampling_event = sampling_event;
 	current_sampling_thread = ep_rt_thread_get_handle ();

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

@@ -637,6 +637,25 @@ ep_rt_config_value_get_enable_stackwalk (void)
 	return value_uint32_t != 0;
 }
 
+static
+inline
+uint32_t
+ep_rt_config_value_get_sampling_rate (void)
+{
+	uint32_t value_uint32_t = 0;
+	gchar *value = g_getenv ("DOTNET_EventPipeThreadSamplingRate");
+	if (!value)
+		value = g_getenv ("COMPlus_EventPipeThreadSamplingRate");
+	if (value) {
+		gchar *endptr = NULL;
+		guint64 parsed = strtoull (value, &endptr, 10);
+		if (endptr != value && *endptr == '\0' && value [0] != '-' && parsed <= G_MAXUINT32)
+			value_uint32_t = (uint32_t)parsed;
+	}
+	g_free (value);
+	return value_uint32_t;
+}
+
 /*
  * EventPipeSampleProfiler.
  */

src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.targets

@@ -482,9 +482,22 @@ Copyright (c) .NET Foundation. All rights reserved.
     </ItemGroup>
   </Target>
 
-  <Target Name="_AddWasmDiagnosticPortsEnvironmentVariable">
+  <Target Name="_AddWasmDiagnosticPortsEnvironmentVariable" Condition="'$(EnableDiagnostics)' == 'true'">
+    <PropertyGroup>
+      <_WasmPerfInstFilter>$(WasmPerformanceInstrumentation)</_WasmPerfInstFilter>
+      <_WasmPerfInstInterval></_WasmPerfInstInterval>
+      <_WasmPerfInstDescriptor></_WasmPerfInstDescriptor>
+      <_WasmPerfInstInterval Condition="$(WasmPerformanceInstrumentation.Contains(',interval='))">$(WasmPerformanceInstrumentation.Substring($([MSBuild]::Add($(WasmPerformanceInstrumentation.IndexOf(',interval=')), 10))))</_WasmPerfInstInterval>
+      <_WasmPerfInstFilter Condition="$(WasmPerformanceInstrumentation.Contains(',interval='))">$(WasmPerformanceInstrumentation.Substring(0, $(WasmPerformanceInstrumentation.IndexOf(',interval='))))</_WasmPerfInstFilter>
+      <_WasmPerfInstInterval Condition="'$(_WasmPerfInstInterval)' != '' and $(_WasmPerfInstInterval.Contains(','))">$(_WasmPerfInstInterval.Substring(0, $(_WasmPerfInstInterval.IndexOf(','))))</_WasmPerfInstInterval>
+      <_WasmPerfInstDescriptor Condition="'$(_WasmPerfInstFilter)' != '' and '$(UseMonoRuntime)' != 'false'">eventpipe,callspec=$(_WasmPerfInstFilter)</_WasmPerfInstDescriptor>
+      <_WasmPerfInstFilter Condition="'$(_WasmPerfInstFilter)' == 'all' and '$(UseMonoRuntime)' == 'false'">*</_WasmPerfInstFilter>
+      <_WasmPerfInstDescriptor Condition="'$(_WasmPerfInstFilter)' != '' and '$(UseMonoRuntime)' == 'false'">$(_WasmPerfInstFilter)</_WasmPerfInstDescriptor>
+    </PropertyGroup>
     <ItemGroup>
       <WasmEnvironmentVariable Include="DOTNET_DiagnosticPorts" Value="$(DiagnosticPorts)" Condition="'$(DiagnosticPorts)' != ''"/>
+      <WasmEnvironmentVariable Include="DOTNET_WasmPerformanceInstrumentation" Value="$(_WasmPerfInstDescriptor)" Condition="'$(_WasmPerfInstDescriptor)' != ''" />
+      <WasmEnvironmentVariable Condition="'$(_WasmPerfInstInterval)' != ''" Include="DOTNET_EventPipeThreadSamplingRate" Value="$(_WasmPerfInstInterval)" />
     </ItemGroup>
   </Target>
 

src/native/eventpipe/ds-ipc-pal-websocket.h

@@ -53,11 +53,17 @@ struct _DiagnosticsIpcStream {
 };
 #endif
 
+#ifdef __cplusplus
+extern "C" {
+#endif
 extern int ds_rt_websocket_poll (int client_socket);
 extern int ds_rt_websocket_create (const char* url);
-extern int ds_rt_websocket_recv (int client_socket, const uint8_t* buffer, uint32_t bytes_to_read);
+extern int ds_rt_websocket_recv (int client_socket, uint8_t* buffer, uint32_t bytes_to_read);
 extern int ds_rt_websocket_send (int client_socket, const uint8_t* buffer, uint32_t bytes_to_write);
 extern int ds_rt_websocket_close(int client_socket);
+#ifdef __cplusplus
+}
+#endif
 
 #endif /* ENABLE_PERFTRACING */
 #endif /* __DIAGNOSTICS_IPC_PAL_WEB_SOCKET_H__ */

src/native/eventpipe/ep-rt.h

@@ -200,6 +200,11 @@ inline
 bool
 ep_rt_config_value_get_enable_stackwalk (void);
 
+static
+inline
+uint32_t
+ep_rt_config_value_get_sampling_rate (void);
+
 /*
  * EventPipeSampleProfiler.
  */

src/native/eventpipe/ep.c

@@ -1496,7 +1496,13 @@ ep_init (void)
 #else // PERFTRACING_DISABLE_THREADS
 	const uint32_t default_profiler_sample_rate_in_nanoseconds = 5000000; // 5 msec.
 #endif // PERFTRACING_DISABLE_THREADS
-	ep_sample_profiler_set_sampling_rate (default_profiler_sample_rate_in_nanoseconds);
+
+	// Allow overriding the sampling rate via DOTNET_EventPipeThreadSamplingRate (in milliseconds).
+	uint32_t configured_rate_ms = ep_rt_config_value_get_sampling_rate ();
+	if (configured_rate_ms > 0)
+		ep_sample_profiler_set_sampling_rate ((uint64_t)configured_rate_ms * 1000000);
+	else
+		ep_sample_profiler_set_sampling_rate (default_profiler_sample_rate_in_nanoseconds);
 
 	_ep_deferred_enable_session_ids = dn_vector_alloc_t (EventPipeSessionID);
 	_ep_deferred_disable_session_ids = dn_vector_alloc_t (EventPipeSessionID);