From c9a6759335a562b5bc5ad070cc009d90f40a8461 Mon Sep 17 00:00:00 2001
From: Nikolai Vazquez <hello@nikolaivazquez.com>
Date: Fri, 27 Oct 2023 10:31:19 -0400
Subject: [PATCH] Serialize AArch64 timestamp counter

---
 src/time/timestamp/tsc/aarch64.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/time/timestamp/tsc/aarch64.rs b/src/time/timestamp/tsc/aarch64.rs
index deff9ee..e064fcd 100644
--- a/src/time/timestamp/tsc/aarch64.rs
+++ b/src/time/timestamp/tsc/aarch64.rs
@@ -27,7 +27,9 @@ pub(crate) fn timestamp() -> u64 {
     unsafe {
         let timestamp: u64;
         asm!(
-            "mrs {}, cntvct_el0",
+            "isb sy
+            mrs {}, cntvct_el0
+            isb sy",
             out(reg) timestamp,
             // Leave off `nomem` because this should be a compiler fence.
             options(nostack, preserves_flags),