From 02b59ba8f79d43805635b2d58752a01759e66d1c Mon Sep 17 00:00:00 2001
From: Geoffrey McRae <geoff@hostfission.com>
Date: Tue, 21 Dec 2021 10:47:11 +1100
Subject: [PATCH] [client] x11: don't use the atomic msc value when we already
 have it

---
 client/displayservers/X11/x11.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/client/displayservers/X11/x11.c b/client/displayservers/X11/x11.c
index ca2616eb..7de18334 100644
--- a/client/displayservers/X11/x11.c
+++ b/client/displayservers/X11/x11.c
@@ -84,7 +84,7 @@ static void x11XInputEvent(XGenericEventCookie *cookie);
 static void x11XPresentEvent(XGenericEventCookie *cookie);
 static void x11GrabPointer(void);
 
-static void x11DoPresent(void)
+static void x11DoPresent(uint64_t msc)
 {
   static bool startup = true;
   if (startup)
@@ -114,7 +114,6 @@ static void x11DoPresent(void)
 
   static bool first   = true;
   static uint64_t lastMsc = 0;
-  uint64_t msc = atomic_load(&x11.presentMsc);
 
   uint64_t refill;
   if (!first)
@@ -686,7 +685,7 @@ static bool x11Init(const LG_DSInitParams params)
   }
 
   if (x11.jitRender)
-    x11DoPresent();
+    x11DoPresent(0);
 
   return true;
 
@@ -1338,10 +1337,10 @@ static void x11XPresentEvent(XGenericEventCookie *cookie)
     case PresentCompleteNotify:
     {
       XPresentCompleteNotifyEvent * e = cookie->data;
+      x11DoPresent(e->msc);
       atomic_store(&x11.presentMsc, e->msc);
       atomic_store(&x11.presentUst, e->ust);
       lgSignalEvent(x11.frameEvent);
-      x11DoPresent();
       break;
     }
   }