Bug 1763593 - Bypass NS_DispatchToMainThread's assert while handling the leak. r=TravisLong

Differential Revision: https://phabricator.services.mozilla.com/D144175

toolkit/components/glean/build_scripts/glean_parser_ext/templates/gifft.jinja2

@@ -14,6 +14,7 @@ Jinja2 template is not. Pleas file bugs! #}
 {% if probe_type == "Scalar" %}
 #include "mozilla/Tuple.h"
 #include "nsClassHashtable.h"
+#include "nsIThread.h"
 #include "nsTHashMap.h"
 {% endif %}
 #include "nsThreadUtils.h"
@@ -52,10 +53,15 @@ static inline Maybe<TimerToStampMutex::AutoLock> GetTimerIdToStartsLock() {
     // In that event we leak. Grab a pointer so we have something to NS_RELEASE
     // in that case.
     nsIRunnable* temp = cleanupFn.get();
-    if (NS_FAILED(NS_DispatchToMainThread(cleanupFn.forget()))) {
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread)))
+      || NS_FAILED(mainThread->Dispatch(cleanupFn.forget(), nsIThread::DISPATCH_NORMAL))
+    ) {
       // Failed to dispatch cleanup routine.
-      // First, un-leak the runnable:
-      NS_RELEASE(temp);
+      // First, un-leak the runnable (but only if we actually attempted dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
       // Next, cleanup immediately, and allow metrics to try again later.
       *lock = nullptr;
       return Nothing();
@@ -93,10 +99,15 @@ static inline Maybe<SubmetricToMirrorMutex::AutoLock> GetLabeledMirrorLock() {
     // In that event we leak. Grab a pointer so we have something to NS_RELEASE
     // in that case.
     nsIRunnable* temp = cleanupFn.get();
-    if (NS_FAILED(NS_DispatchToMainThread(cleanupFn.forget()))) {
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread)))
+      || NS_FAILED(mainThread->Dispatch(cleanupFn.forget(), nsIThread::DISPATCH_NORMAL))
+    ) {
       // Failed to dispatch cleanup routine.
-      // First, un-leak the runnable:
-      NS_RELEASE(temp);
+      // First, un-leak the runnable (but only if we actually attempted dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
       // Next, cleanup immediately, and allow metrics to try again later.
       *lock = nullptr;
       return Nothing();
@@ -154,10 +165,15 @@ static inline Maybe<TimesToStartsMutex::AutoLock> GetTimesToStartsLock() {
     // In that event we leak. Grab a pointer so we have something to NS_RELEASE
     // in that case.
     nsIRunnable* temp = cleanupFn.get();
-    if (NS_FAILED(NS_DispatchToMainThread(cleanupFn.forget()))) {
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread)))
+      || NS_FAILED(mainThread->Dispatch(cleanupFn.forget(), nsIThread::DISPATCH_NORMAL))
+    ) {
       // Failed to dispatch cleanup routine.
-      // First, un-leak the runnable:
-      NS_RELEASE(temp);
+      // First, un-leak the runnable (but only if we actually attempted dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
       // Next, cleanup immediately, and allow metrics to try again later.
       *lock = nullptr;
       return Nothing();

toolkit/components/glean/tests/pytest/gifft_output_Histogram

@@ -44,10 +44,15 @@ static inline Maybe<TimerToStampMutex::AutoLock> GetTimerIdToStartsLock() {
     // In that event we leak. Grab a pointer so we have something to NS_RELEASE
     // in that case.
     nsIRunnable* temp = cleanupFn.get();
-    if (NS_FAILED(NS_DispatchToMainThread(cleanupFn.forget()))) {
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread)))
+      || NS_FAILED(mainThread->Dispatch(cleanupFn.forget(), nsIThread::DISPATCH_NORMAL))
+    ) {
       // Failed to dispatch cleanup routine.
-      // First, un-leak the runnable:
-      NS_RELEASE(temp);
+      // First, un-leak the runnable (but only if we actually attempted dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
       // Next, cleanup immediately, and allow metrics to try again later.
       *lock = nullptr;
       return Nothing();

toolkit/components/glean/tests/pytest/gifft_output_Scalar

@@ -11,6 +11,7 @@
 #include "mozilla/DataMutex.h"
 #include "mozilla/Tuple.h"
 #include "nsClassHashtable.h"
+#include "nsIThread.h"
 #include "nsTHashMap.h"
 #include "nsThreadUtils.h"
 
@@ -50,10 +51,15 @@ static inline Maybe<SubmetricToMirrorMutex::AutoLock> GetLabeledMirrorLock() {
     // In that event we leak. Grab a pointer so we have something to NS_RELEASE
     // in that case.
     nsIRunnable* temp = cleanupFn.get();
-    if (NS_FAILED(NS_DispatchToMainThread(cleanupFn.forget()))) {
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread)))
+      || NS_FAILED(mainThread->Dispatch(cleanupFn.forget(), nsIThread::DISPATCH_NORMAL))
+    ) {
       // Failed to dispatch cleanup routine.
-      // First, un-leak the runnable:
-      NS_RELEASE(temp);
+      // First, un-leak the runnable (but only if we actually attempted dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
       // Next, cleanup immediately, and allow metrics to try again later.
       *lock = nullptr;
       return Nothing();
@@ -111,10 +117,15 @@ static inline Maybe<TimesToStartsMutex::AutoLock> GetTimesToStartsLock() {
     // In that event we leak. Grab a pointer so we have something to NS_RELEASE
     // in that case.
     nsIRunnable* temp = cleanupFn.get();
-    if (NS_FAILED(NS_DispatchToMainThread(cleanupFn.forget()))) {
+    nsCOMPtr<nsIThread> mainThread;
+    if (NS_FAILED(NS_GetMainThread(getter_AddRefs(mainThread)))
+      || NS_FAILED(mainThread->Dispatch(cleanupFn.forget(), nsIThread::DISPATCH_NORMAL))
+    ) {
       // Failed to dispatch cleanup routine.
-      // First, un-leak the runnable:
-      NS_RELEASE(temp);
+      // First, un-leak the runnable (but only if we actually attempted dispatch)
+      if (!cleanupFn) {
+        NS_RELEASE(temp);
+      }
       // Next, cleanup immediately, and allow metrics to try again later.
       *lock = nullptr;
       return Nothing();