This source file includes following definitions.
- perf_time_to_tsc
- tsc_to_perf_time
- rdtsc
1
2 #include <linux/compiler.h>
3 #include <linux/types.h>
4
5 #include "tsc.h"
6
7 u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc)
8 {
9 u64 t, quot, rem;
10
11 t = ns - tc->time_zero;
12 quot = t / tc->time_mult;
13 rem = t % tc->time_mult;
14 return (quot << tc->time_shift) +
15 (rem << tc->time_shift) / tc->time_mult;
16 }
17
18 u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
19 {
20 u64 quot, rem;
21
22 quot = cyc >> tc->time_shift;
23 rem = cyc & (((u64)1 << tc->time_shift) - 1);
24 return tc->time_zero + quot * tc->time_mult +
25 ((rem * tc->time_mult) >> tc->time_shift);
26 }
27
28 u64 __weak rdtsc(void)
29 {
30 return 0;
31 }