From 6abd515c051b6dcb545e1033ff129aaaf7293917 Mon Sep 17 00:00:00 2001
From: Marvin Borner
Date: Sun, 10 May 2020 13:35:43 +0200
Subject: Added basic spinlock
---
src/kernel/io/io.c | 8 ++++++++
1 file changed, 8 insertions(+)
(limited to 'src')
diff --git a/src/kernel/io/io.c b/src/kernel/io/io.c
index 2d9d009..dfd9efa 100644
--- a/src/kernel/io/io.c
+++ b/src/kernel/io/io.c
@@ -66,6 +66,14 @@ void outl(u16 port, u32 data)
asm volatile("outl %0, %1" ::"a"(data), "Nd"(port));
}
+void spinlock(int *ptr)
+{
+ int prev;
+ do
+ asm volatile("lock xchgl %0,%1" : "=a"(prev) : "m"(*ptr), "a"(1));
+ while (prev);
+}
+
void init_serial()
{
outb(0x3f8 + 1, 0x00);
--
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