From 10d42721e97fed6932af9d2f77334b391b3b07ed Mon Sep 17 00:00:00 2001
From: Mathieu Maret <mathieu.maret@gmail.com>
Date: Wed, 15 Sep 2021 21:51:58 +0200
Subject: [PATCH] Add read_cycle_counter

---
 core/time.c | 7 +++++++
 core/time.h | 3 +++
 2 files changed, 10 insertions(+)

diff --git a/core/time.c b/core/time.c
index 4bd7f42..b08b77d 100644
--- a/core/time.c
+++ b/core/time.c
@@ -27,3 +27,10 @@ unsigned long usecs_to_jiffies(const unsigned int u)
     // This could overflow
     return (u * HZ) / 1000000L;
 }
+
+#include <x86intrin.h>
+inline uint64_t read_cycle_counter()
+{
+        uint64_t tsc = __rdtsc();
+        return tsc;
+}
diff --git a/core/time.h b/core/time.h
index 699b33d..a5a4bdd 100644
--- a/core/time.h
+++ b/core/time.h
@@ -1,4 +1,5 @@
 #pragma once
+#include <stdint.h>
 
 #define HZ 100
 /*
@@ -50,3 +51,5 @@ unsigned int jiffies_to_msecs(const unsigned long j);
 unsigned int jiffies_to_usecs(const unsigned long j);
 unsigned long msecs_to_jiffies(const unsigned int m);
 unsigned long usecs_to_jiffies(const unsigned int u);
+
+uint64_t read_cycle_counter();