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v0.8.1
swh:1:snp:a902887e4be9191b7c6c4406aa06b31c1ce2c7cc
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Tip revision: 9735a22799b9214d17d3c231fe377fc852f042e9 authored by Linus Torvalds on 03 April 2016, 14:09:40 UTC
Linux 4.6-rc2
Tip revision: 9735a22
tsc.c
#include <linux/compiler.h>
#include <linux/types.h>

#include "tsc.h"

u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc)
{
	u64 t, quot, rem;

	t = ns - tc->time_zero;
	quot = t / tc->time_mult;
	rem  = t % tc->time_mult;
	return (quot << tc->time_shift) +
	       (rem << tc->time_shift) / tc->time_mult;
}

u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
{
	u64 quot, rem;

	quot = cyc >> tc->time_shift;
	rem  = cyc & (((u64)1 << tc->time_shift) - 1);
	return tc->time_zero + quot * tc->time_mult +
	       ((rem * tc->time_mult) >> tc->time_shift);
}

u64 __weak rdtsc(void)
{
	return 0;
}
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