2 * linux/include/asm-i386/tsc.h
4 * i386 TSC related functions
6 #ifndef _ARCH_x86_64_TSC_H
7 #define _ARCH_x86_64_TSC_H
10 #include <arch/processor.h>
12 typedef uint64_t cycles_t;
15 * Returns the current value of the CPU's cycle counter.
17 * NOTE: This is not serializing. It doesn't necessarily wait for previous
18 * instructions to complete before reading the cycle counter. Also,
19 * subsequent instructions could potentially begin execution before
20 * the cycle counter is read.
22 static __always_inline cycles_t
31 * This is a synchronizing version of get_cycles(). It ensures that all
32 * previous instructions have completed before reading the cycle counter.
34 static __always_inline cycles_t