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>
29 lines
572 B
C
29 lines
572 B
C
/*
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* Copyright 2006 Andi Kleen, SUSE Labs.
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* Subject to the GNU Public License, v.2
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*
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* Fast user context implementation of getcpu()
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*/
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#include <linux/kernel.h>
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#include <linux/getcpu.h>
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#include <linux/time.h>
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#include <asm/vgtod.h>
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notrace long
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__vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
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{
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unsigned int p;
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p = __getcpu();
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if (cpu)
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*cpu = p & VGETCPU_CPU_MASK;
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if (node)
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*node = p >> 12;
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return 0;
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}
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long getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
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__attribute__((weak, alias("__vdso_getcpu")));
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