tor-browser

commit 8d73b933b1a5af0cc15c2d680f077944780bf53d
parent 2133e66f54eb62c4e5047a4188f1cc8ddddf1318
Author: Markus Stange <mstange.moz@gmail.com>
Date:   Thu, 23 Oct 2025 16:07:53 +0000

Bug 1996052 - Limit the default QOS change from bug 1995638 to macOS 26+ (Tahoe or later), to minimize risk. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D269786

Diffstat:
M
xpcom/threads/nsThread.cpp
 | 
9
+++++++--

1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/xpcom/threads/nsThread.cpp b/xpcom/threads/nsThread.cpp
@@ -85,6 +85,8 @@ using GetCurrentThreadStackLimitsFn = void(WINAPI*)(PULONG_PTR LowLimit,
 #  include <mach/mach.h>
 #  include <mach/thread_policy.h>
 #  include <sys/qos.h>
+
+#  include "nsCocoaFeatures.h"
 #endif
 
 #ifdef MOZ_CANARY
@@ -338,8 +340,11 @@ void nsThread::ThreadFunc(void* aArg) {
   self->InitCommon();
 
 #ifdef XP_MACOSX
-  // Use "User Initiated" as the default quality of service.
-  pthread_set_qos_class_self_np(QOS_CLASS_USER_INITIATED, 0);
+  if (nsCocoaFeatures::OnTahoeOrLater()) {
+    // On macOS 26+, use "User Initiated" as the default quality of service.
+    // It may make sense to do this on all versions of macOS.
+    pthread_set_qos_class_self_np(QOS_CLASS_USER_INITIATED, 0);
+  }
 #endif
 
   // Inform the ThreadManager