auto import from //depot/cupcake/@135843
diff --git a/libc/kernel/arch-x86/asm/tsc.h b/libc/kernel/arch-x86/asm/tsc.h
new file mode 100644
index 0000000..2528cd1
--- /dev/null
+++ b/libc/kernel/arch-x86/asm/tsc.h
@@ -0,0 +1,22 @@
+/****************************************************************************
+ ****************************************************************************
+ ***
+ *** This header was automatically generated from a Linux kernel header
+ *** of the same name, to make information necessary for userspace to
+ *** call into the kernel available to libc. It contains only constants,
+ *** structures, and macros generated from the original header, and thus,
+ *** contains no copyrightable information.
+ ***
+ ****************************************************************************
+ ****************************************************************************/
+#ifndef _ASM_X86_TSC_H
+#define _ASM_X86_TSC_H
+
+#include <asm/processor.h>
+
+#define NS_SCALE 10
+#define US_SCALE 32
+
+typedef unsigned long long cycles_t;
+
+#endif