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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   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.
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  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
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  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_config.h>
  47 #include <rte_log.h>
  48 #include <rte_power.h>
  49 #include <rte_spinlock.h>
  50
  51 #include "power_manager.h"
  52
  53 #define RTE_LOGTYPE_POWER_MANAGER RTE_LOGTYPE_USER1
  54
  55 #define POWER_SCALE_CORE(DIRECTION, core_num , ret) do { \
  56         if (core_num >= POWER_MGR_MAX_CPUS) \
  57                 return -1; \
  58         if (!(global_enabled_cpus & (1ULL << core_num))) \
  59                 return -1; \
  60         rte_spinlock_lock(&global_core_freq_info[core_num].power_sl); \
  61         ret = rte_power_freq_##DIRECTION(core_num); \
  62         rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl); \
  63 } while (0)
  64
  65 #define POWER_SCALE_MASK(DIRECTION, core_mask, ret) do { \
  66         int i; \
  67         for (i = 0; core_mask; core_mask &= ~(1 << i++)) { \
  68                 if ((core_mask >> i) & 1) { \
  69                         if (!(global_enabled_cpus & (1ULL << i))) \
  70                                 continue; \
  71                         rte_spinlock_lock(&global_core_freq_info[i].power_sl); \
  72                         if (rte_power_freq_##DIRECTION(i) != 1) \
  73                                 ret = -1; \
  74                         rte_spinlock_unlock(&global_core_freq_info[i].power_sl); \
  75                 } \
  76         } \
  77 } while (0)
  78
  79 struct freq_info {
  80         rte_spinlock_t power_sl;
  81         uint32_t freqs[RTE_MAX_LCORE_FREQS];
  82         unsigned num_freqs;
  83 } __rte_cache_aligned;
  84
  85 static struct freq_info global_core_freq_info[POWER_MGR_MAX_CPUS];
  86
  87 static uint64_t global_enabled_cpus;
  88
  89 #define SYSFS_CPU_PATH "/sys/devices/system/cpu/cpu%u/topology/core_id"
  90
  91 static unsigned
  92 set_host_cpus_mask(void)
  93 {
  94         char path[PATH_MAX];
  95         unsigned i;
  96         unsigned num_cpus = 0;
  97
  98         for (i = 0; i < POWER_MGR_MAX_CPUS; i++) {
  99                 snprintf(path, sizeof(path), SYSFS_CPU_PATH, i);
 100                 if (access(path, F_OK) == 0) {
 101                         global_enabled_cpus |= 1ULL << i;
 102                         num_cpus++;
 103                 } else
 104                         return num_cpus;
 105         }
 106         return num_cpus;
 107 }
 108
 109 int
 110 power_manager_init(void)
 111 {
 112         unsigned i, num_cpus;
 113         uint64_t cpu_mask;
 114         int ret = 0;
 115
 116         num_cpus = set_host_cpus_mask();
 117         if (num_cpus == 0) {
 118                 RTE_LOG(ERR, POWER_MANAGER, "Unable to detected host CPUs, please "
 119                         "ensure that sufficient privileges exist to inspect sysfs\n");
 120                 return -1;
 121         }
 122         rte_power_set_env(PM_ENV_ACPI_CPUFREQ);
 123         cpu_mask = global_enabled_cpus;
 124         for (i = 0; cpu_mask; cpu_mask &= ~(1 << i++)) {
 125                 if (rte_power_init(i) < 0 || rte_power_freqs(i,
 126                                 global_core_freq_info[i].freqs,
 127                                 RTE_MAX_LCORE_FREQS) == 0) {
 128                         RTE_LOG(ERR, POWER_MANAGER, "Unable to initialize power manager "
 129                                         "for core %u\n", i);
 130                         global_enabled_cpus &= ~(1 << i);
 131                         num_cpus--;
 132                         ret = -1;
 133                 }
 134                 rte_spinlock_init(&global_core_freq_info[i].power_sl);
 135         }
 136         RTE_LOG(INFO, POWER_MANAGER, "Detected %u host CPUs , enabled core mask:"
 137                                         " 0x%"PRIx64"\n", num_cpus, global_enabled_cpus);
 138         return ret;
 139
 140 }
 141
 142 uint32_t
 143 power_manager_get_current_frequency(unsigned core_num)
 144 {
 145         uint32_t freq, index;
 146
 147         if (core_num >= POWER_MGR_MAX_CPUS) {
 148                 RTE_LOG(ERR, POWER_MANAGER, "Core(%u) is out of range 0...%d\n",
 149                                 core_num, POWER_MGR_MAX_CPUS-1);
 150                 return -1;
 151         }
 152         if (!(global_enabled_cpus & (1ULL << core_num)))
 153                 return 0;
 154
 155         rte_spinlock_lock(&global_core_freq_info[core_num].power_sl);
 156         index = rte_power_get_freq(core_num);
 157         rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl);
 158         if (index >= POWER_MGR_MAX_CPUS)
 159                 freq = 0;
 160         else
 161                 freq = global_core_freq_info[core_num].freqs[index];
 162
 163         return freq;
 164 }
 165
 166 int
 167 power_manager_exit(void)
 168 {
 169         unsigned int i;
 170         int ret = 0;
 171
 172         for (i = 0; global_enabled_cpus; global_enabled_cpus &= ~(1 << i++)) {
 173                 if (rte_power_exit(i) < 0) {
 174                         RTE_LOG(ERR, POWER_MANAGER, "Unable to shutdown power manager "
 175                                         "for core %u\n", i);
 176                         ret = -1;
 177                 }
 178         }
 179         global_enabled_cpus = 0;
 180         return ret;
 181 }
 182
 183 int
 184 power_manager_scale_mask_up(uint64_t core_mask)
 185 {
 186         int ret = 0;
 187
 188         POWER_SCALE_MASK(up, core_mask, ret);
 189         return ret;
 190 }
 191
 192 int
 193 power_manager_scale_mask_down(uint64_t core_mask)
 194 {
 195         int ret = 0;
 196
 197         POWER_SCALE_MASK(down, core_mask, ret);
 198         return ret;
 199 }
 200
 201 int
 202 power_manager_scale_mask_min(uint64_t core_mask)
 203 {
 204         int ret = 0;
 205
 206         POWER_SCALE_MASK(min, core_mask, ret);
 207         return ret;
 208 }
 209
 210 int
 211 power_manager_scale_mask_max(uint64_t core_mask)
 212 {
 213         int ret = 0;
 214
 215         POWER_SCALE_MASK(max, core_mask, ret);
 216         return ret;
 217 }
 218
 219 int
 220 power_manager_scale_core_up(unsigned core_num)
 221 {
 222         int ret = 0;
 223
 224         POWER_SCALE_CORE(up, core_num, ret);
 225         return ret;
 226 }
 227
 228 int
 229 power_manager_scale_core_down(unsigned core_num)
 230 {
 231         int ret = 0;
 232
 233         POWER_SCALE_CORE(down, core_num, ret);
 234         return ret;
 235 }
 236
 237 int
 238 power_manager_scale_core_min(unsigned core_num)
 239 {
 240         int ret = 0;
 241
 242         POWER_SCALE_CORE(min, core_num, ret);
 243         return ret;
 244 }
 245
 246 int
 247 power_manager_scale_core_max(unsigned core_num)
 248 {
 249         int ret = 0;
 250
 251         POWER_SCALE_CORE(max, core_num, ret);
 252         return ret;
 253 }