ceph/src/spdk/dpdk/lib/librte_eal/common/include/generic/rte_cycles.h

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation.
   3  * Copyright(c) 2013 6WIND S.A.
   4  */
   5
   6 #ifndef _RTE_CYCLES_H_
   7 #define _RTE_CYCLES_H_
   8
   9 /**
  10  * @file
  11  *
  12  * Simple Time Reference Functions (Cycles and HPET).
  13  */
  14
  15 #include <stdint.h>
  16 #include <rte_compat.h>
  17 #include <rte_debug.h>
  18 #include <rte_atomic.h>
  19
  20 #define MS_PER_S 1000
  21 #define US_PER_S 1000000
  22 #define NS_PER_S 1000000000
  23
  24 enum timer_source {
  25         EAL_TIMER_TSC = 0,
  26         EAL_TIMER_HPET
  27 };
  28 extern enum timer_source eal_timer_source;
  29
  30 /**
  31  * Get the measured frequency of the RDTSC counter
  32  *
  33  * @return
  34  *   The TSC frequency for this lcore
  35  */
  36 uint64_t
  37 rte_get_tsc_hz(void);
  38
  39 /**
  40  * Return the number of TSC cycles since boot
  41  *
  42   * @return
  43  *   the number of cycles
  44  */
  45 static inline uint64_t
  46 rte_get_tsc_cycles(void);
  47
  48 #ifdef RTE_LIBEAL_USE_HPET
  49 /**
  50  * Return the number of HPET cycles since boot
  51  *
  52  * This counter is global for all execution units. The number of
  53  * cycles in one second can be retrieved using rte_get_hpet_hz().
  54  *
  55  * @return
  56  *   the number of cycles
  57  */
  58 uint64_t
  59 rte_get_hpet_cycles(void);
  60
  61 /**
  62  * Get the number of HPET cycles in one second.
  63  *
  64  * @return
  65  *   The number of cycles in one second.
  66  */
  67 uint64_t
  68 rte_get_hpet_hz(void);
  69
  70 /**
  71  * Initialise the HPET for use. This must be called before the rte_get_hpet_hz
  72  * and rte_get_hpet_cycles APIs are called. If this function does not succeed,
  73  * then the HPET functions are unavailable and should not be called.
  74  *
  75  * @param make_default
  76  *      If set, the hpet timer becomes the default timer whose values are
  77  *      returned by the rte_get_timer_hz/cycles API calls
  78  *
  79  * @return
  80  *      0 on success,
  81  *      -1 on error, and the make_default parameter is ignored.
  82  */
  83 int rte_eal_hpet_init(int make_default);
  84
  85 #endif
  86
  87 /**
  88  * Get the number of cycles since boot from the default timer.
  89  *
  90  * @return
  91  *   The number of cycles
  92  */
  93 static inline uint64_t
  94 rte_get_timer_cycles(void)
  95 {
  96 #ifdef RTE_LIBEAL_USE_HPET
  97         switch(eal_timer_source) {
  98         case EAL_TIMER_TSC:
  99 #endif
 100                 return rte_get_tsc_cycles();
 101 #ifdef RTE_LIBEAL_USE_HPET
 102         case EAL_TIMER_HPET:
 103                 return rte_get_hpet_cycles();
 104         default: rte_panic("Invalid timer source specified\n");
 105         }
 106 #endif
 107 }
 108
 109 /**
 110  * Get the number of cycles in one second for the default timer.
 111  *
 112  * @return
 113  *   The number of cycles in one second.
 114  */
 115 static inline uint64_t
 116 rte_get_timer_hz(void)
 117 {
 118 #ifdef RTE_LIBEAL_USE_HPET
 119         switch(eal_timer_source) {
 120         case EAL_TIMER_TSC:
 121 #endif
 122                 return rte_get_tsc_hz();
 123 #ifdef RTE_LIBEAL_USE_HPET
 124         case EAL_TIMER_HPET:
 125                 return rte_get_hpet_hz();
 126         default: rte_panic("Invalid timer source specified\n");
 127         }
 128 #endif
 129 }
 130 /**
 131  * Wait at least us microseconds.
 132  * This function can be replaced with user-defined function.
 133  * @see rte_delay_us_callback_register
 134  *
 135  * @param us
 136  *   The number of microseconds to wait.
 137  */
 138 extern void
 139 (*rte_delay_us)(unsigned int us);
 140
 141 /**
 142  * Wait at least ms milliseconds.
 143  *
 144  * @param ms
 145  *   The number of milliseconds to wait.
 146  */
 147 static inline void
 148 rte_delay_ms(unsigned ms)
 149 {
 150         rte_delay_us(ms * 1000);
 151 }
 152
 153 /**
 154  * Blocking delay function.
 155  *
 156  * @param us
 157  *   Number of microseconds to wait.
 158  */
 159 void rte_delay_us_block(unsigned int us);
 160
 161 /**
 162  * Delay function that uses system sleep.
 163  * Does not block the CPU core.
 164  *
 165  * @param us
 166  *   Number of microseconds to wait.
 167  */
 168 void __rte_experimental
 169 rte_delay_us_sleep(unsigned int us);
 170
 171 /**
 172  * Replace rte_delay_us with user defined function.
 173  *
 174  * @param userfunc
 175  *   User function which replaces rte_delay_us. rte_delay_us_block restores
 176  *   builtin block delay function.
 177  */
 178 void rte_delay_us_callback_register(void(*userfunc)(unsigned int));
 179
 180 #endif /* _RTE_CYCLES_H_ */