ceph/src/spdk/dpdk/lib/librte_eal/common/eal_common_timer.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation
   3  */
   4
   5 #include <string.h>
   6 #include <stdio.h>
   7 #include <unistd.h>
   8 #include <inttypes.h>
   9 #include <sys/types.h>
  10 #include <errno.h>
  11
  12 #include <rte_common.h>
  13 #include <rte_log.h>
  14 #include <rte_cycles.h>
  15 #include <rte_pause.h>
  16
  17 #include "eal_private.h"
  18
  19 /* The frequency of the RDTSC timer resolution */
  20 static uint64_t eal_tsc_resolution_hz;
  21
  22 /* Pointer to user delay function */
  23 void (*rte_delay_us)(unsigned int) = NULL;
  24
  25 void
  26 rte_delay_us_block(unsigned int us)
  27 {
  28         const uint64_t start = rte_get_timer_cycles();
  29         const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
  30         while ((rte_get_timer_cycles() - start) < ticks)
  31                 rte_pause();
  32 }
  33
  34 uint64_t
  35 rte_get_tsc_hz(void)
  36 {
  37         return eal_tsc_resolution_hz;
  38 }
  39
  40 static uint64_t
  41 estimate_tsc_freq(void)
  42 {
  43         RTE_LOG(WARNING, EAL, "WARNING: TSC frequency estimated roughly"
  44                 " - clock timings may be less accurate.\n");
  45         /* assume that the sleep(1) will sleep for 1 second */
  46         uint64_t start = rte_rdtsc();
  47         sleep(1);
  48         return rte_rdtsc() - start;
  49 }
  50
  51 void
  52 set_tsc_freq(void)
  53 {
  54         uint64_t freq;
  55
  56         freq = get_tsc_freq_arch();
  57         if (!freq)
  58                 freq = get_tsc_freq();
  59         if (!freq)
  60                 freq = estimate_tsc_freq();
  61
  62         RTE_LOG(DEBUG, EAL, "TSC frequency is ~%" PRIu64 " KHz\n", freq / 1000);
  63         eal_tsc_resolution_hz = freq;
  64 }
  65
  66 void rte_delay_us_callback_register(void (*userfunc)(unsigned int))
  67 {
  68         rte_delay_us = userfunc;
  69 }
  70
  71 RTE_INIT(rte_timer_init)
  72 {
  73         /* set rte_delay_us_block as a delay function */
  74         rte_delay_us_callback_register(rte_delay_us_block);
  75 }