lib/librte_eal/common/include/arch/x86/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_X86_64_H_
   7 #define _RTE_CYCLES_X86_64_H_
   8
   9 #ifdef __cplusplus
  10 extern "C" {
  11 #endif
  12
  13 #include "generic/rte_cycles.h"
  14
  15 #ifdef RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT
  16 /* Global switch to use VMWARE mapping of TSC instead of RDTSC */
  17 extern int rte_cycles_vmware_tsc_map;
  18 #include <rte_branch_prediction.h>
  19 #endif
  20 #include <rte_common.h>
  21 #include <rte_config.h>
  22
  23 static inline uint64_t
  24 rte_rdtsc(void)
  25 {
  26         union {
  27                 uint64_t tsc_64;
  28                 RTE_STD_C11
  29                 struct {
  30                         uint32_t lo_32;
  31                         uint32_t hi_32;
  32                 };
  33         } tsc;
  34
  35 #ifdef RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT
  36         if (unlikely(rte_cycles_vmware_tsc_map)) {
  37                 /* ecx = 0x10000 corresponds to the physical TSC for VMware */
  38                 asm volatile("rdpmc" :
  39                              "=a" (tsc.lo_32),
  40                              "=d" (tsc.hi_32) :
  41                              "c"(0x10000));
  42                 return tsc.tsc_64;
  43         }
  44 #endif
  45
  46         asm volatile("rdtsc" :
  47                      "=a" (tsc.lo_32),
  48                      "=d" (tsc.hi_32));
  49         return tsc.tsc_64;
  50 }
  51
  52 static inline uint64_t
  53 rte_rdtsc_precise(void)
  54 {
  55         rte_mb();
  56         return rte_rdtsc();
  57 }
  58
  59 static inline uint64_t
  60 rte_get_tsc_cycles(void) { return rte_rdtsc(); }
  61
  62 #ifdef __cplusplus
  63 }
  64 #endif
  65
  66 #endif /* _RTE_CYCLES_X86_64_H_ */