ceph/src/seastar/dpdk/lib/librte_eal/common/include/arch/x86/rte_cycles.h

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33 /*   BSD LICENSE
  34  *
  35  *   Copyright(c) 2013 6WIND.
  36  *
  37  *   Redistribution and use in source and binary forms, with or without
  38  *   modification, are permitted provided that the following conditions
  39  *   are met:
  40  *
  41  *     * Redistributions of source code must retain the above copyright
  42  *       notice, this list of conditions and the following disclaimer.
  43  *     * Redistributions in binary form must reproduce the above copyright
  44  *       notice, this list of conditions and the following disclaimer in
  45  *       the documentation and/or other materials provided with the
  46  *       distribution.
  47  *     * Neither the name of 6WIND S.A. nor the names of its
  48  *       contributors may be used to endorse or promote products derived
  49  *       from this software without specific prior written permission.
  50  *
  51  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  52  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  53  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  54  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  55  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  56  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  57  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  58  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  59  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  60  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  61  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  62  */
  63
  64 #ifndef _RTE_CYCLES_X86_64_H_
  65 #define _RTE_CYCLES_X86_64_H_
  66
  67 #ifdef __cplusplus
  68 extern "C" {
  69 #endif
  70
  71 #include "generic/rte_cycles.h"
  72
  73 #ifdef RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT
  74 /* Global switch to use VMWARE mapping of TSC instead of RDTSC */
  75 extern int rte_cycles_vmware_tsc_map;
  76 #include <rte_branch_prediction.h>
  77 #endif
  78 #include <rte_common.h>
  79
  80 static inline uint64_t
  81 rte_rdtsc(void)
  82 {
  83         union {
  84                 uint64_t tsc_64;
  85                 RTE_STD_C11
  86                 struct {
  87                         uint32_t lo_32;
  88                         uint32_t hi_32;
  89                 };
  90         } tsc;
  91
  92 #ifdef RTE_LIBRTE_EAL_VMWARE_TSC_MAP_SUPPORT
  93         if (unlikely(rte_cycles_vmware_tsc_map)) {
  94                 /* ecx = 0x10000 corresponds to the physical TSC for VMware */
  95                 asm volatile("rdpmc" :
  96                              "=a" (tsc.lo_32),
  97                              "=d" (tsc.hi_32) :
  98                              "c"(0x10000));
  99                 return tsc.tsc_64;
 100         }
 101 #endif
 102
 103         asm volatile("rdtsc" :
 104                      "=a" (tsc.lo_32),
 105                      "=d" (tsc.hi_32));
 106         return tsc.tsc_64;
 107 }
 108
 109 static inline uint64_t
 110 rte_rdtsc_precise(void)
 111 {
 112         rte_mb();
 113         return rte_rdtsc();
 114 }
 115
 116 static inline uint64_t
 117 rte_get_tsc_cycles(void) { return rte_rdtsc(); }
 118
 119 #ifdef __cplusplus
 120 }
 121 #endif
 122
 123 #endif /* _RTE_CYCLES_X86_64_H_ */