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38 #include <sys/types.h>
41 #include <rte_common.h>
43 #include <rte_cycles.h>
44 #include <rte_pause.h>
46 #include "eal_private.h"
48 /* The frequency of the RDTSC timer resolution */
49 static uint64_t eal_tsc_resolution_hz;
51 /* Pointer to user delay function */
52 void (*rte_delay_us)(unsigned int) = NULL;
55 rte_delay_us_block(unsigned int us)
57 const uint64_t start = rte_get_timer_cycles();
58 const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
59 while ((rte_get_timer_cycles() - start) < ticks)
66 return eal_tsc_resolution_hz;
70 estimate_tsc_freq(void)
72 RTE_LOG(WARNING, EAL, "WARNING: TSC frequency estimated roughly"
73 " - clock timings may be less accurate.\n");
74 /* assume that the sleep(1) will sleep for 1 second */
75 uint64_t start = rte_rdtsc();
77 return rte_rdtsc() - start;
83 uint64_t freq = get_tsc_freq();
86 freq = estimate_tsc_freq();
88 RTE_LOG(DEBUG, EAL, "TSC frequency is ~%" PRIu64 " KHz\n", freq / 1000);
89 eal_tsc_resolution_hz = freq;
92 void rte_delay_us_callback_register(void (*userfunc)(unsigned int))
94 rte_delay_us = userfunc;
97 static void __attribute__((constructor))
100 /* set rte_delay_us_block as a delay function */
101 rte_delay_us_callback_register(rte_delay_us_block);