From: Ben Adams <thundercat@illyriad.co.uk>
Date: Thu, 7 Jan 2021 23:18:27 +0000 (+0000)
Subject: Use faster Guid/Name lookup for EventSource (#45745)
X-Git-Tag: submit/tizen/20210909.063632~3892
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4b8d10154c39b1f56424d4ba2068a3150d90d475;p=platform%2Fupstream%2Fdotnet%2Fruntime.git

Use faster Guid/Name lookup for EventSource (#45745)
---

diff --git a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs
index c63d070..1e67a98 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs
@@ -2912,8 +2912,16 @@ namespace System.Diagnostics.Tracing
                 if (eventSourceAttrib != null && eventSourceAttrib.LocalizationResources != null)
                     resources = new ResourceManager(eventSourceAttrib.LocalizationResources, eventSourceType.Assembly);
 
-                manifest = new ManifestBuilder(GetName(eventSourceType, flags), GetGuid(eventSourceType), eventSourceDllName,
+                if (source is not null)
+                {
+                    // We have the source so don't need to use reflection to get the Name and Guid
+                    manifest = new ManifestBuilder(source.Name, source.Guid, eventSourceDllName, resources, flags);
+                }
+                else
+                {
+                    manifest = new ManifestBuilder(GetName(eventSourceType, flags), GetGuid(eventSourceType), eventSourceDllName,
                                                resources, flags);
+                }
 
                 // Add an entry unconditionally for event ID 0 which will be for a string message.
                 manifest.StartEvent("EventSourceMessage", new EventAttribute(0) { Level = EventLevel.LogAlways, Task = (EventTask)0xFFFE });