examples/vm_power_manager/power_manager.c

/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2010-2014 Intel Corporation
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <fcntl.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>

#include <sys/sysinfo.h>
#include <sys/types.h>

#include <rte_log.h>
#include <rte_power.h>
#include <rte_spinlock.h>

#include "channel_manager.h"
#include "power_manager.h"
#include "oob_monitor.h"

#define POWER_SCALE_CORE(DIRECTION, core_num , ret) do { \
    if (core_num >= ci.core_count) \
        return -1; \
    if (!(ci.cd[core_num].global_enabled_cpus)) \
        return -1; \
    rte_spinlock_lock(&global_core_freq_info[core_num].power_sl); \
    ret = rte_power_freq_##DIRECTION(core_num); \
    rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl); \
} while (0)

struct freq_info {
    rte_spinlock_t power_sl;
    uint32_t freqs[RTE_MAX_LCORE_FREQS];
    unsigned num_freqs;
} __rte_cache_aligned;

static struct freq_info global_core_freq_info[RTE_MAX_LCORE];

struct core_info ci;

#define SYSFS_CPU_PATH "/sys/devices/system/cpu/cpu%u/topology/core_id"

struct core_info *
get_core_info(void)
{
    return &ci;
}

int
core_info_init(void)
{
    struct core_info *ci;
    int i;

    ci = get_core_info();

    ci->core_count = get_nprocs_conf();
    ci->cd = malloc(ci->core_count * sizeof(struct core_details));
    memset(ci->cd, 0, ci->core_count * sizeof(struct core_details));
    if (!ci->cd) {
        RTE_LOG(ERR, POWER_MANAGER, "Failed to allocate memory for core info.");
        return -1;
    }
    for (i = 0; i < ci->core_count; i++) {
        ci->cd[i].global_enabled_cpus = 1;
        ci->cd[i].branch_ratio_threshold = BRANCH_RATIO_THRESHOLD;
    }
    printf("%d cores in system\n", ci->core_count);
    return 0;
}

int
power_manager_init(void)
{
    unsigned int i, num_cpus = 0, num_freqs = 0;
    int ret = 0;
    struct core_info *ci;
    unsigned int max_core_num;

    rte_power_set_env(PM_ENV_NOT_SET);

    ci = get_core_info();
    if (!ci) {
        RTE_LOG(ERR, POWER_MANAGER,
                "Failed to get core info!\n");
        return -1;
    }

    if (ci->core_count > RTE_MAX_LCORE)
        max_core_num = RTE_MAX_LCORE;
    else
        max_core_num = ci->core_count;

    for (i = 0; i < max_core_num; i++) {
        if (ci->cd[i].global_enabled_cpus) {
            if (rte_power_init(i) < 0)
                RTE_LOG(ERR, POWER_MANAGER,
                        "Unable to initialize power manager "
                        "for core %u\n", i);
            num_cpus++;
            num_freqs = rte_power_freqs(i,
                    global_core_freq_info[i].freqs,
                    RTE_MAX_LCORE_FREQS);
            if (num_freqs == 0) {
                RTE_LOG(ERR, POWER_MANAGER,
                    "Unable to get frequency list for core %u\n",
                    i);
                ci->cd[i].oob_enabled = 0;
                ret = -1;
            }
            global_core_freq_info[i].num_freqs = num_freqs;

            rte_spinlock_init(&global_core_freq_info[i].power_sl);
        }
        if (ci->cd[i].oob_enabled)
            add_core_to_monitor(i);
    }
    RTE_LOG(INFO, POWER_MANAGER, "Managing %u cores out of %u available host cores\n",
            num_cpus, ci->core_count);
    return ret;

}

uint32_t
power_manager_get_current_frequency(unsigned core_num)
{
    uint32_t freq, index;

    if (core_num >= RTE_MAX_LCORE) {
        RTE_LOG(ERR, POWER_MANAGER, "Core(%u) is out of range 0...%d\n",
                core_num, RTE_MAX_LCORE-1);
        return -1;
    }
    if (!(ci.cd[core_num].global_enabled_cpus))
        return 0;

    rte_spinlock_lock(&global_core_freq_info[core_num].power_sl);
    index = rte_power_get_freq(core_num);
    rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl);
    if (index >= RTE_MAX_LCORE_FREQS)
        freq = 0;
    else
        freq = global_core_freq_info[core_num].freqs[index];

    return freq;
}

int
power_manager_exit(void)
{
    unsigned int i;
    int ret = 0;
    struct core_info *ci;
    unsigned int max_core_num;

    ci = get_core_info();
    if (!ci) {
        RTE_LOG(ERR, POWER_MANAGER,
                "Failed to get core info!\n");
        return -1;
    }

    if (ci->core_count > RTE_MAX_LCORE)
        max_core_num = RTE_MAX_LCORE;
    else
        max_core_num = ci->core_count;

    for (i = 0; i < max_core_num; i++) {
        if (ci->cd[i].global_enabled_cpus) {
            if (rte_power_exit(i) < 0) {
                RTE_LOG(ERR, POWER_MANAGER, "Unable to shutdown power manager "
                        "for core %u\n", i);
                ret = -1;
            }
            ci->cd[i].global_enabled_cpus = 0;
        }
        remove_core_from_monitor(i);
    }
    return ret;
}

int
power_manager_scale_core_up(unsigned core_num)
{
    int ret = 0;

    POWER_SCALE_CORE(up, core_num, ret);
    return ret;
}

int
power_manager_scale_core_down(unsigned core_num)
{
    int ret = 0;

    POWER_SCALE_CORE(down, core_num, ret);
    return ret;
}

int
power_manager_scale_core_min(unsigned core_num)
{
    int ret = 0;

    POWER_SCALE_CORE(min, core_num, ret);
    return ret;
}

int
power_manager_scale_core_max(unsigned core_num)
{
    int ret = 0;

    POWER_SCALE_CORE(max, core_num, ret);
    return ret;
}

int
power_manager_enable_turbo_core(unsigned int core_num)
{
    int ret = 0;

    POWER_SCALE_CORE(enable_turbo, core_num, ret);
    return ret;
}

int
power_manager_disable_turbo_core(unsigned int core_num)
{
    int ret = 0;

    POWER_SCALE_CORE(disable_turbo, core_num, ret);
    return ret;
}

int
power_manager_scale_core_med(unsigned int core_num)
{
    int ret = 0;
    struct core_info *ci;

    ci = get_core_info();
    if (core_num >= RTE_MAX_LCORE)
        return -1;
    if (!(ci->cd[core_num].global_enabled_cpus))
        return -1;
    rte_spinlock_lock(&global_core_freq_info[core_num].power_sl);
    ret = rte_power_set_freq(core_num,
                global_core_freq_info[core_num].num_freqs / 2);
    rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl);
    return ret;
}