examples/vm_power_manager/power_manager.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
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  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.
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  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
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  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
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  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
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <stdint.h>
  37 #include <inttypes.h>
  38 #include <sys/un.h>
  39 #include <fcntl.h>
  40 #include <unistd.h>
  41 #include <dirent.h>
  42 #include <errno.h>
  43
  44 #include <sys/types.h>
  45
  46 #include <rte_log.h>
  47 #include <rte_power.h>
  48 #include <rte_spinlock.h>
  49
  50 #include "power_manager.h"
  51
  52 #define RTE_LOGTYPE_POWER_MANAGER RTE_LOGTYPE_USER1
  53
  54 #define POWER_SCALE_CORE(DIRECTION, core_num , ret) do { \
  55         if (core_num >= POWER_MGR_MAX_CPUS) \
  56                 return -1; \
  57         if (!(global_enabled_cpus & (1ULL << core_num))) \
  58                 return -1; \
  59         rte_spinlock_lock(&global_core_freq_info[core_num].power_sl); \
  60         ret = rte_power_freq_##DIRECTION(core_num); \
  61         rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl); \
  62 } while (0)
  63
  64 #define POWER_SCALE_MASK(DIRECTION, core_mask, ret) do { \
  65         int i; \
  66         for (i = 0; core_mask; core_mask &= ~(1 << i++)) { \
  67                 if ((core_mask >> i) & 1) { \
  68                         if (!(global_enabled_cpus & (1ULL << i))) \
  69                                 continue; \
  70                         rte_spinlock_lock(&global_core_freq_info[i].power_sl); \
  71                         if (rte_power_freq_##DIRECTION(i) != 1) \
  72                                 ret = -1; \
  73                         rte_spinlock_unlock(&global_core_freq_info[i].power_sl); \
  74                 } \
  75         } \
  76 } while (0)
  77
  78 struct freq_info {
  79         rte_spinlock_t power_sl;
  80         uint32_t freqs[RTE_MAX_LCORE_FREQS];
  81         unsigned num_freqs;
  82 } __rte_cache_aligned;
  83
  84 static struct freq_info global_core_freq_info[POWER_MGR_MAX_CPUS];
  85
  86 static uint64_t global_enabled_cpus;
  87
  88 #define SYSFS_CPU_PATH "/sys/devices/system/cpu/cpu%u/topology/core_id"
  89
  90 static unsigned
  91 set_host_cpus_mask(void)
  92 {
  93         char path[PATH_MAX];
  94         unsigned i;
  95         unsigned num_cpus = 0;
  96
  97         for (i = 0; i < POWER_MGR_MAX_CPUS; i++) {
  98                 snprintf(path, sizeof(path), SYSFS_CPU_PATH, i);
  99                 if (access(path, F_OK) == 0) {
 100                         global_enabled_cpus |= 1ULL << i;
 101                         num_cpus++;
 102                 } else
 103                         return num_cpus;
 104         }
 105         return num_cpus;
 106 }
 107
 108 int
 109 power_manager_init(void)
 110 {
 111         unsigned i, num_cpus;
 112         uint64_t cpu_mask;
 113         int ret = 0;
 114
 115         num_cpus = set_host_cpus_mask();
 116         if (num_cpus == 0) {
 117                 RTE_LOG(ERR, POWER_MANAGER, "Unable to detected host CPUs, please "
 118                         "ensure that sufficient privileges exist to inspect sysfs\n");
 119                 return -1;
 120         }
 121         rte_power_set_env(PM_ENV_ACPI_CPUFREQ);
 122         cpu_mask = global_enabled_cpus;
 123         for (i = 0; cpu_mask; cpu_mask &= ~(1 << i++)) {
 124                 if (rte_power_init(i) < 0 || rte_power_freqs(i,
 125                                 global_core_freq_info[i].freqs,
 126                                 RTE_MAX_LCORE_FREQS) == 0) {
 127                         RTE_LOG(ERR, POWER_MANAGER, "Unable to initialize power manager "
 128                                         "for core %u\n", i);
 129                         global_enabled_cpus &= ~(1 << i);
 130                         num_cpus--;
 131                         ret = -1;
 132                 }
 133                 rte_spinlock_init(&global_core_freq_info[i].power_sl);
 134         }
 135         RTE_LOG(INFO, POWER_MANAGER, "Detected %u host CPUs , enabled core mask:"
 136                                         " 0x%"PRIx64"\n", num_cpus, global_enabled_cpus);
 137         return ret;
 138
 139 }
 140
 141 uint32_t
 142 power_manager_get_current_frequency(unsigned core_num)
 143 {
 144         uint32_t freq, index;
 145
 146         if (core_num >= POWER_MGR_MAX_CPUS) {
 147                 RTE_LOG(ERR, POWER_MANAGER, "Core(%u) is out of range 0...%d\n",
 148                                 core_num, POWER_MGR_MAX_CPUS-1);
 149                 return -1;
 150         }
 151         if (!(global_enabled_cpus & (1ULL << core_num)))
 152                 return 0;
 153
 154         rte_spinlock_lock(&global_core_freq_info[core_num].power_sl);
 155         index = rte_power_get_freq(core_num);
 156         rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl);
 157         if (index >= POWER_MGR_MAX_CPUS)
 158                 freq = 0;
 159         else
 160                 freq = global_core_freq_info[core_num].freqs[index];
 161
 162         return freq;
 163 }
 164
 165 int
 166 power_manager_exit(void)
 167 {
 168         unsigned int i;
 169         int ret = 0;
 170
 171         for (i = 0; global_enabled_cpus; global_enabled_cpus &= ~(1 << i++)) {
 172                 if (rte_power_exit(i) < 0) {
 173                         RTE_LOG(ERR, POWER_MANAGER, "Unable to shutdown power manager "
 174                                         "for core %u\n", i);
 175                         ret = -1;
 176                 }
 177         }
 178         global_enabled_cpus = 0;
 179         return ret;
 180 }
 181
 182 int
 183 power_manager_scale_mask_up(uint64_t core_mask)
 184 {
 185         int ret = 0;
 186
 187         POWER_SCALE_MASK(up, core_mask, ret);
 188         return ret;
 189 }
 190
 191 int
 192 power_manager_scale_mask_down(uint64_t core_mask)
 193 {
 194         int ret = 0;
 195
 196         POWER_SCALE_MASK(down, core_mask, ret);
 197         return ret;
 198 }
 199
 200 int
 201 power_manager_scale_mask_min(uint64_t core_mask)
 202 {
 203         int ret = 0;
 204
 205         POWER_SCALE_MASK(min, core_mask, ret);
 206         return ret;
 207 }
 208
 209 int
 210 power_manager_scale_mask_max(uint64_t core_mask)
 211 {
 212         int ret = 0;
 213
 214         POWER_SCALE_MASK(max, core_mask, ret);
 215         return ret;
 216 }
 217
 218 int
 219 power_manager_scale_core_up(unsigned core_num)
 220 {
 221         int ret = 0;
 222
 223         POWER_SCALE_CORE(up, core_num, ret);
 224         return ret;
 225 }
 226
 227 int
 228 power_manager_scale_core_down(unsigned core_num)
 229 {
 230         int ret = 0;
 231
 232         POWER_SCALE_CORE(down, core_num, ret);
 233         return ret;
 234 }
 235
 236 int
 237 power_manager_scale_core_min(unsigned core_num)
 238 {
 239         int ret = 0;
 240
 241         POWER_SCALE_CORE(min, core_num, ret);
 242         return ret;
 243 }
 244
 245 int
 246 power_manager_scale_core_max(unsigned core_num)
 247 {
 248         int ret = 0;
 249
 250         POWER_SCALE_CORE(max, core_num, ret);
 251         return ret;
 252 }