// SPDX-License-Identifier: GPL-2.0-only
/*
* (C) 2016 SUSE Software Solutions GmbH
* Thomas Renninger <[email protected]>
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <stdio.h>
#include <dirent.h>
#include "powercap.h"
static unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen)
{
int fd;
ssize_t numread;
fd = open(path, O_RDONLY);
if (fd == -1)
return 0;
numread = read(fd, buf, buflen - 1);
if (numread < 1) {
close(fd);
return 0;
}
buf[numread] = '\0';
close(fd);
return (unsigned int) numread;
}
static int sysfs_get_enabled(char *path, int *mode)
{
int fd;
char yes_no;
int ret = 0;
*mode = 0;
fd = open(path, O_RDONLY);
if (fd == -1) {
ret = -1;
goto out;
}
if (read(fd, &yes_no, 1) != 1) {
ret = -1;
goto out_close;
}
if (yes_no == '1') {
*mode = 1;
goto out_close;
} else if (yes_no == '0') {
goto out_close;
} else {
ret = -1;
goto out_close;
}
out_close:
close(fd);
out:
return ret;
}
int powercap_get_enabled(int *mode)
{
char path[SYSFS_PATH_MAX] = PATH_TO_POWERCAP "/intel-rapl/enabled";
return sysfs_get_enabled(path, mode);
}
/*
* TODO: implement function. Returns dummy 0 for now.
*/
int powercap_set_enabled(int mode)
{
return 0;
}
/*
* Hardcoded, because rapl is the only powercap implementation
- * this needs to get more generic if more powercap implementations
* should show up
*/
int powercap_get_driver(char *driver, int buflen)
{
char file[SYSFS_PATH_MAX] = PATH_TO_RAPL;
struct stat statbuf;
if (stat(file, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) {
driver = "";
return -1;
} else if (buflen > 10) {
strcpy(driver, "intel-rapl");
return 0;
} else
return -1;
}
enum powercap_get64 {
GET_ENERGY_UJ,
GET_MAX_ENERGY_RANGE_UJ,
GET_POWER_UW,
GET_MAX_POWER_RANGE_UW,
MAX_GET_64_FILES
};
static const char *powercap_get64_files[MAX_GET_64_FILES] = {
[GET_POWER_UW] = "power_uw",
[GET_MAX_POWER_RANGE_UW] = "max_power_range_uw",
[GET_ENERGY_UJ] = "energy_uj",
[GET_MAX_ENERGY_RANGE_UJ] = "max_energy_range_uj",
};
static int sysfs_powercap_get64_val(struct powercap_zone *zone,
enum powercap_get64 which,
uint64_t *val)
{
char file[SYSFS_PATH_MAX] = PATH_TO_POWERCAP "/";
int ret;
char buf[MAX_LINE_LEN];
strcat(file, zone->sys_name);
strcat(file, "/");
strcat(file, powercap_get64_files[which]);
ret = sysfs_read_file(file, buf, MAX_LINE_LEN);
if (ret < 0)
return ret;
if (ret == 0)
return -1;
*val = strtoll(buf, NULL, 10);
return 0;
}
int powercap_get_max_energy_range_uj(struct powercap_zone *zone, uint64_t *val)
{
return sysfs_powercap_get64_val(zone, GET_MAX_ENERGY_RANGE_UJ, val);
}
int powercap_get_energy_uj(struct powercap_zone *zone, uint64_t *val)
{
return sysfs_powercap_get64_val(zone, GET_ENERGY_UJ, val);
}
int powercap_get_max_power_range_uw(struct powercap_zone *zone, uint64_t *val)
{
return sysfs_powercap_get64_val(zone, GET_MAX_POWER_RANGE_UW, val);
}
int powercap_get_power_uw(struct powercap_zone *zone, uint64_t *val)
{
return sysfs_powercap_get64_val(zone, GET_POWER_UW, val);
}
int powercap_zone_get_enabled(struct powercap_zone *zone, int *mode)
{
char path[SYSFS_PATH_MAX] = PATH_TO_POWERCAP;
if ((strlen(PATH_TO_POWERCAP) + strlen(zone->sys_name)) +
strlen("/enabled") + 1 >= SYSFS_PATH_MAX)
return -1;
strcat(path, "/");
strcat(path, zone->sys_name);
strcat(path, "/enabled");
return sysfs_get_enabled(path, mode);
}
int powercap_zone_set_enabled(struct powercap_zone *zone, int mode)
{
/* To be done if needed */
return 0;
}
int powercap_read_zone(struct powercap_zone *zone)
{
struct dirent *dent;
DIR *zone_dir;
char sysfs_dir[SYSFS_PATH_MAX] = PATH_TO_POWERCAP;
struct powercap_zone *child_zone;
char file[SYSFS_PATH_MAX] = PATH_TO_POWERCAP;
int i, ret = 0;
uint64_t val = 0;
strcat(sysfs_dir, "/");
strcat(sysfs_dir, zone->sys_name);
zone_dir = opendir(sysfs_dir);
if (zone_dir == NULL)
return -1;
strcat(file, "/");
strcat(file, zone->sys_name);
strcat(file, "/name");
sysfs_read_file(file, zone->name, MAX_LINE_LEN);
if (zone->parent)
zone->tree_depth = zone->parent->tree_depth + 1;
ret = powercap_get_energy_uj(zone, &val);
if (ret == 0)
zone->has_energy_uj = 1;
ret = powercap_get_power_uw(zone, &val);
if (ret == 0)
zone->has_power_uw = 1;
while ((dent = readdir(zone_dir)) != NULL) {
struct stat st;
if (strcmp(dent->d_name, ".") == 0 || strcmp(dent->d_name, "..") == 0)
continue;
if (stat(dent->d_name, &st) != 0 || !S_ISDIR(st.st_mode))
if (fstatat(dirfd(zone_dir), dent->d_name, &st, 0) < 0)
continue;
if (strncmp(dent->d_name, "intel-rapl:", 11) != 0)
continue;
child_zone = calloc(1, sizeof(struct powercap_zone));
if (child_zone == NULL)
return -1;
for (i = 0; i < POWERCAP_MAX_CHILD_ZONES; i++) {
if (zone->children[i] == NULL) {
zone->children[i] = child_zone;
break;
}
if (i == POWERCAP_MAX_CHILD_ZONES - 1) {
free(child_zone);
fprintf(stderr, "Reached POWERCAP_MAX_CHILD_ZONES %d\n",
POWERCAP_MAX_CHILD_ZONES);
return -1;
}
}
strcpy(child_zone->sys_name, zone->sys_name);
strcat(child_zone->sys_name, "/");
strcat(child_zone->sys_name, dent->d_name);
child_zone->parent = zone;
if (zone->tree_depth >= POWERCAP_MAX_TREE_DEPTH) {
fprintf(stderr, "Maximum zone hierarchy depth[%d] reached\n",
POWERCAP_MAX_TREE_DEPTH);
ret = -1;
break;
}
powercap_read_zone(child_zone);
}
closedir(zone_dir);
return ret;
}
struct powercap_zone *powercap_init_zones(void)
{
int enabled;
struct powercap_zone *root_zone;
int ret;
char file[SYSFS_PATH_MAX] = PATH_TO_RAPL "/enabled";
ret = sysfs_get_enabled(file, &enabled);
if (ret)
return NULL;
if (!enabled)
return NULL;
root_zone = calloc(1, sizeof(struct powercap_zone));
if (!root_zone)
return NULL;
strcpy(root_zone->sys_name, "intel-rapl/intel-rapl:0");
powercap_read_zone(root_zone);
return root_zone;
}
/* Call function *f on the passed zone and all its children */
int powercap_walk_zones(struct powercap_zone *zone,
int (*f)(struct powercap_zone *zone))
{
int i, ret;
if (!zone)
return -1;
ret = f(zone);
if (ret)
return ret;
for (i = 0; i < POWERCAP_MAX_CHILD_ZONES; i++) {
if (zone->children[i] != NULL)
powercap_walk_zones(zone->children[i], f);
}
return 0;
}
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