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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;
50 /* Pointer to user delay function */
51 void (*rte_delay_us)(unsigned int) = NULL;
54 rte_delay_us_block(unsigned int us)
56 const uint64_t start = rte_get_timer_cycles();
57 const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
58 while ((rte_get_timer_cycles() - start) < ticks)
65 return eal_tsc_resolution_hz;
69 estimate_tsc_freq(void)
71 RTE_LOG(WARNING, EAL, "WARNING: TSC frequency estimated roughly"
72 " - clock timings may be less accurate.\n");
73 /* assume that the sleep(1) will sleep for 1 second */
74 uint64_t start = rte_rdtsc();
76 return rte_rdtsc() - start;
82 uint64_t freq = get_tsc_freq();
85 freq = estimate_tsc_freq();
87 RTE_LOG(DEBUG, EAL, "TSC frequency is ~%" PRIu64 " KHz\n", freq / 1000);
88 eal_tsc_resolution_hz = freq;
91 void rte_delay_us_callback_register(void (*userfunc)(unsigned int))
93 rte_delay_us = userfunc;
96 static void __attribute__((constructor))
99 /* set rte_delay_us_block as a delay function */
100 rte_delay_us_callback_register(rte_delay_us_block);