e76b027e64
LSL is faster than RDTSCP and works everywhere; there's no need to switch between them depending on CPU. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Andi Kleen <andi@firstfloor.org> Link: http://lkml.kernel.org/r/72f73d5ec4514e02bba345b9759177ef03742efb.1414706021.git.luto@amacapital.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
28 lines
572 B
C
28 lines
572 B
C
/*
|
|
* Copyright 2006 Andi Kleen, SUSE Labs.
|
|
* Subject to the GNU Public License, v.2
|
|
*
|
|
* Fast user context implementation of getcpu()
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/getcpu.h>
|
|
#include <linux/time.h>
|
|
#include <asm/vgtod.h>
|
|
|
|
notrace long
|
|
__vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
|
|
{
|
|
unsigned int p;
|
|
|
|
p = __getcpu();
|
|
|
|
if (cpu)
|
|
*cpu = p & VGETCPU_CPU_MASK;
|
|
if (node)
|
|
*node = p >> 12;
|
|
return 0;
|
|
}
|
|
|
|
long getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
|
|
__attribute__((weak, alias("__vdso_getcpu")));
|