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38 #include <sys/types.h>
41 #include <rte_common.h>
43 #include <rte_cycles.h>
45 #include "eal_private.h"
47 /* The frequency of the RDTSC timer resolution */
48 static uint64_t eal_tsc_resolution_hz;
51 rte_delay_us(unsigned us)
53 const uint64_t start = rte_get_timer_cycles();
54 const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
55 while ((rte_get_timer_cycles() - start) < ticks)
62 return eal_tsc_resolution_hz;
66 estimate_tsc_freq(void)
68 RTE_LOG(WARNING, EAL, "WARNING: TSC frequency estimated roughly"
69 " - clock timings may be less accurate.\n");
70 /* assume that the sleep(1) will sleep for 1 second */
71 uint64_t start = rte_rdtsc();
73 return rte_rdtsc() - start;
79 uint64_t freq = get_tsc_freq();
82 freq = estimate_tsc_freq();
84 RTE_LOG(DEBUG, EAL, "TSC frequency is ~%" PRIu64 " KHz\n", freq / 1000);
85 eal_tsc_resolution_hz = freq;