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35 #ifndef LTHREAD_TIMER_H_
36 #define LTHREAD_TIMER_H_
42 #include "lthread_int.h"
43 #include "lthread_sched.h"
46 static inline uint64_t
47 _ns_to_clks(uint64_t ns)
50 * clkns needs to be divided by 1E9 to get ns clocks. However,
51 * dividing by this first would lose a lot of accuracy.
52 * Dividing after a multiply by ns, could cause overflow of
53 * uint64_t if ns is about 5 seconds [if we assume a max tsc
54 * rate of 4GHz]. Therefore we first divide by 1E4, then
55 * multiply and finally divide by 1E5. This allows ns to be
56 * values many hours long, without overflow, while still keeping
57 * reasonable accuracy.
59 uint64_t clkns = rte_get_tsc_hz() / 1e4;
69 _timer_start(struct lthread *lt, uint64_t clks)
72 DIAG_EVENT(lt, LT_DIAG_LTHREAD_TMR_START, <->tim, clks);
73 rte_timer_init(<->tim);
74 rte_timer_reset(<->tim,
85 _timer_stop(struct lthread *lt)
88 DIAG_EVENT(lt, LT_DIAG_LTHREAD_TMR_DELETE, <->tim, 0);
89 rte_timer_stop(<->tim);
97 #endif /* LTHREAD_TIMER_H_ */