From 975f77a3bcbe14d891bd3501588065ffe1f8ed04 Mon Sep 17 00:00:00 2001
From: BrahmaMantra <140599389+BrahmaMantra@users.noreply.github.com>
Date: Sun, 19 May 2024 23:27:41 +0800
Subject: [PATCH] =?UTF-8?q?fix(time):=E4=BF=AE=E5=A4=8D=E4=BA=86issue=20#8?=
 =?UTF-8?q?16=20(#830)?=
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---
 kernel/src/time/timekeeping.rs | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/kernel/src/time/timekeeping.rs b/kernel/src/time/timekeeping.rs
index dff0cb91..deaad142 100644
--- a/kernel/src/time/timekeeping.rs
+++ b/kernel/src/time/timekeeping.rs
@@ -164,10 +164,8 @@ impl Timekeeper {
 
     #[inline]
     fn do_read_cpu_cycle_ns(&self) -> usize {
-        CurrentTimeArch::cycles2ns(
-            CurrentTimeArch::get_cycles()
-                .wrapping_sub(self.last_update_cpu_cycle.load(Ordering::SeqCst)),
-        )
+        let prev = self.last_update_cpu_cycle.load(Ordering::SeqCst);
+        CurrentTimeArch::cycles2ns(CurrentTimeArch::get_cycles().wrapping_sub(prev))
     }
 
     fn mark_update_wall_time_ok(&self) {