From 7fe60600b4ab2497b53a7ea02e18b8685f6e2db7 Mon Sep 17 00:00:00 2001
From: tmds <tmds@users.noreply.github.com>
Date: Wed, 6 May 2020 18:28:23 +0000
Subject: [PATCH] Ensure Process.ProcessName doesn't change when setting
 Thread.Name on Linux

Fixes https://github.com/dotnet/runtime/issues/33673

This issue is a side-effect of adding support for setting thread names on Linux in https://github.com/dotnet/coreclr/pull/27182.

cc @janvorli @lpereira @SteveL-MSFT
---
 mono/utils/mono-threads-posix.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/mono/utils/mono-threads-posix.c b/mono/utils/mono-threads-posix.c
index 33afc458a792..f8f21ca67700 100644
--- a/mono/utils/mono-threads-posix.c
+++ b/mono/utils/mono-threads-posix.c
@@ -282,6 +282,15 @@ mono_native_thread_set_name (MonoNativeThreadId tid, const char *name)
 	if (tid != mono_native_thread_id_get ())
 		return;
 
+#if defined(__linux__)
+	/*
+	 * Ignore requests to set the main thread name because
+	 * it causes the value returned by Process.ProcessName to change.
+	 */
+	if (mono_native_thread_os_id_get () == (guint64)getpid ())
+		return;
+#endif
+
 	if (!name) {
 		pthread_setname_np ("");
 	} else {