[Mono]: Add dotnet-gcdump support. (#88634)

Add support for dotnet-gcdump on Mono.

New GC events consumed by dotnet-gcdump has been added to the new ep-rt-mono-runtime-provider.c source file.

Disable experimental EventPipe mono profiler provider by default to preserve resources. It is possible to re-enable it by setting the following env variable, MONO_DIAGNOSTICS=--diagnostic-mono-profiler=enable.

Author: lateralusX

src/coreclr/scripts/genEventPipe.py

@@ -662,8 +662,16 @@ def getMonoEventPipeHelperFileImplPrefix():
     size_t *size,
     bool *fixed_buffer)
 {
-    if (!value)
+    if (!value || value_len == 0) {
+        value_len = sizeof (ep_char16_t);
+        if ((value_len + *offset) > *size)
+            ep_raise_error_if_nok (resize_buffer (buffer, size, *offset, *size + value_len, fixed_buffer));
+        (*buffer) [*offset] = 0;
+        (*offset)++;
+        (*buffer) [*offset] = 0;
+        (*offset)++;
         return true;
+    }
 
     GFixedBufferCustomAllocatorData custom_alloc_data;
     custom_alloc_data.buffer = *buffer + *offset;
@@ -695,9 +703,23 @@ def getMonoEventPipeHelperFileImplPrefix():
     bool *fixed_buffer)
 {
     if (!value)
-        return true;
+        value_len = 0;
+
+    if ((value_len + 1 + *offset) > *size)
+        ep_raise_error_if_nok (resize_buffer (buffer, size, *offset, *size + value_len + 1, fixed_buffer));
+
+    if (value_len != 0) {
+        memcpy (*buffer + *offset, value, value_len);
+        *offset += value_len;
+    }
 
-    return write_buffer ((const uint8_t *)value, (value_len + 1) * sizeof(*value), buffer, offset, size, fixed_buffer);
+    (*buffer) [*offset] = 0;
+    (*offset)++;
+
+    return true;
+
+ep_on_error:
+    return false;
 }
 
 """

src/coreclr/scripts/genEventing.py

@@ -731,7 +731,7 @@ def generatePlatformIndependentFiles(sClrEtwAllMan, incDir, etmDummyFile, extern
 
             eventpipeProviderCtxName = providerSymbol + "_EVENTPIPE_Context"
             if is_windows:
-                Clrallevents.write(('constexpr ' if target_cpp else '') + 'EVENTPIPE_TRACE_CONTEXT ' + eventpipeProviderCtxName + ' = { W("' + providerName + '"), 0, false, 0 };\n')
+                Clrallevents.write(('constexpr ' if target_cpp else 'static const ') + 'EVENTPIPE_TRACE_CONTEXT ' + eventpipeProviderCtxName + ' = { W("' + providerName + '"), 0, false, 0 };\n')
 
             if not is_windows and not write_xplatheader:
                 Clrallevents.write('__attribute__((weak)) EVENTPIPE_TRACE_CONTEXT ' + eventpipeProviderCtxName + ' = { W("' + providerName + '"), 0, false, 0 };\n')
@@ -782,14 +782,14 @@ def generatePlatformIndependentFiles(sClrEtwAllMan, incDir, etmDummyFile, extern
                     symbolName = eventNode.getAttribute('symbol')
                     keywords = eventNode.getAttribute('keywords')
                     level = convertToLevelId(levelName)
-                    Clrproviders.write(("constexpr " if target_cpp else "const ") + "EVENT_DESCRIPTOR " + symbolName + " = { " + str(level) + ", " + hex(getKeywordsMaskCombined(keywords, keywordsToMask)) + " };\n")
+                    Clrproviders.write(("constexpr " if target_cpp else "static const ") + "EVENT_DESCRIPTOR " + symbolName + " = { " + str(level) + ", " + hex(getKeywordsMaskCombined(keywords, keywordsToMask)) + " };\n")
 
                 allProviders.append("&" + providerSymbol + "_LTTNG_Context")
 
             # define and initialize runtime providers' DOTNET_TRACE_CONTEXT depending on the platform
             if not is_windows:
                 Clrproviders.write('#define NB_PROVIDERS ' + str(nbProviders) + '\n')
-                Clrproviders.write(('constexpr ' if target_cpp else 'const ') + 'LTTNG_TRACE_CONTEXT * ALL_LTTNG_PROVIDERS_CONTEXT[NB_PROVIDERS] = { ')
+                Clrproviders.write(('constexpr ' if target_cpp else 'static const ') + 'LTTNG_TRACE_CONTEXT * ALL_LTTNG_PROVIDERS_CONTEXT[NB_PROVIDERS] = { ')
                 Clrproviders.write(', '.join(allProviders))
                 Clrproviders.write(' };\n')
 

src/mono/mono/component/event_pipe.c

@@ -17,7 +17,6 @@
 #include <emscripten/emscripten.h>
 #endif
 
-extern void ep_rt_mono_component_init (void);
 static bool _event_pipe_component_inited = false;
 
 struct _EventPipeProviderConfigurationNative {
@@ -127,7 +126,7 @@ static MonoComponentEventPipe fn_table = {
 	&ep_provider_add_event,
 	&event_pipe_get_session_info,
 	&event_pipe_thread_ctrl_activity_id,
-	&ep_rt_mono_write_event_ee_startup_start,
+	&ep_rt_write_event_ee_startup_start,
 	&ep_rt_write_event_threadpool_worker_thread_start,
 	&ep_rt_write_event_threadpool_worker_thread_stop,
 	&ep_rt_write_event_threadpool_worker_thread_wait,

src/mono/mono/eglib/glib.h

@@ -1635,6 +1635,7 @@ __CAST_UTYPE_TO_STYPE(gunichar, gchar, CHAR_MIN, CHAR_MAX)
 
 #define GLONG_TO_ULONG(v)        G_CAST_TYPE_TO_TYPE(glong, gulong, v)
 #define GULONG_TO_LONG(v)        G_CAST_TYPE_TO_TYPE(gulong, glong, v)
+#define GLONG_TO_UINT32(v)       G_CAST_TYPE_TO_TYPE(glong, guint32, v)
 
 #define GDOUBLE_TO_INT64(v)      G_CAST_TYPE_TO_TYPE(gdouble, gint64, v)
 #define GDOUBLE_TO_UINT64(v)     G_CAST_TYPE_TO_TYPE(gdouble, guint64, v)

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

@@ -214,8 +214,8 @@ static
 uint32_t
 ds_rt_set_environment_variable (const ep_char16_t *name, const ep_char16_t *value)
 {
-	gchar *nameNarrow = ep_rt_utf16le_to_utf8_string (name, ep_rt_utf16_string_len (name));
-	gchar *valueNarrow = ep_rt_utf16le_to_utf8_string (value, ep_rt_utf16_string_len (value));
+	gchar *nameNarrow = ep_rt_utf16le_to_utf8_string (name, -1);
+	gchar *valueNarrow = ep_rt_utf16le_to_utf8_string (value, -1);
 
 	gboolean success = g_setenv(nameNarrow, valueNarrow, true);