From c9c362e16ad30f092ee385cf8ba63b0b518334f0 Mon Sep 17 00:00:00 2001
From: Jakob Bornecrantz <jakob@collabora.com>
Date: Mon, 12 Apr 2021 20:17:10 +0100
Subject: [PATCH] c/multi: Overwrite stale scheduled frames

---
 src/xrt/compositor/multi/comp_multi_compositor.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/xrt/compositor/multi/comp_multi_compositor.c b/src/xrt/compositor/multi/comp_multi_compositor.c
index 587305716..6caa6bf7b 100644
--- a/src/xrt/compositor/multi/comp_multi_compositor.c
+++ b/src/xrt/compositor/multi/comp_multi_compositor.c
@@ -431,6 +431,13 @@ wait_for_scheduled_free(struct multi_compositor *mc)
 
 	// Block here if the scheduled slot is not clear.
 	while (mc->scheduled.active) {
+
+		// Replace the scheduled frame if it's in the past.
+		uint64_t now_ns = os_monotonic_get_ns();
+		if (mc->scheduled.display_time_ns < now_ns) {
+			break;
+		}
+
 		os_mutex_unlock(&mc->slot_lock);
 
 		os_nanosleep(U_TIME_1MS_IN_NS);