blob: 5ebd436838769561bfd426a8b9c398347dc210e5 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Basic resctrl file system operations
*
* Copyright (C) 2018 Intel Corporation
*
* Authors:
* Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
* Fenghua Yu <fenghua.yu@intel.com>
*/
#include <fcntl.h>
#include <limits.h>
#include "resctrl.h"
static int find_resctrl_mount(char *buffer)
{
FILE *mounts;
char line[256], *fs, *mntpoint;
mounts = fopen("/proc/mounts", "r");
if (!mounts) {
perror("/proc/mounts");
return -ENXIO;
}
while (!feof(mounts)) {
if (!fgets(line, 256, mounts))
break;
fs = strtok(line, " \t");
if (!fs)
continue;
mntpoint = strtok(NULL, " \t");
if (!mntpoint)
continue;
fs = strtok(NULL, " \t");
if (!fs)
continue;
if (strcmp(fs, "resctrl"))
continue;
fclose(mounts);
if (buffer)
strncpy(buffer, mntpoint, 256);
return 0;
}
fclose(mounts);
return -ENOENT;
}
/*
* mount_resctrlfs - Mount resctrl FS at /sys/fs/resctrl
*
* Mounts resctrl FS. Fails if resctrl FS is already mounted to avoid
* pre-existing settings interfering with the test results.
*
* Return: 0 on success, non-zero on failure
*/
int mount_resctrlfs(void)
{
int ret;
ret = find_resctrl_mount(NULL);
if (ret != -ENOENT)
return -1;
ksft_print_msg("Mounting resctrl to \"%s\"\n", RESCTRL_PATH);
ret = mount("resctrl", RESCTRL_PATH, "resctrl", 0, NULL);
if (ret)
perror("# mount");
return ret;
}
int umount_resctrlfs(void)
{
char mountpoint[256];
int ret;
ret = find_resctrl_mount(mountpoint);
if (ret == -ENOENT)
return 0;
if (ret)
return ret;
if (umount(mountpoint)) {
perror("# Unable to umount resctrl");
return errno;
}
return 0;
}
/*
* get_resource_id - Get socket number/l3 id for a specified CPU
* @cpu_no: CPU number
* @resource_id: Socket number or l3_id
*
* Return: >= 0 on success, < 0 on failure.
*/
int get_resource_id(int cpu_no, int *resource_id)
{
char phys_pkg_path[1024];
FILE *fp;
if (get_vendor() == ARCH_AMD)
sprintf(phys_pkg_path, "%s%d/cache/index3/id",
PHYS_ID_PATH, cpu_no);
else
sprintf(phys_pkg_path, "%s%d/topology/physical_package_id",
PHYS_ID_PATH, cpu_no);
fp = fopen(phys_pkg_path, "r");
if (!fp) {
perror("Failed to open physical_package_id");
return -1;
}
if (fscanf(fp, "%d", resource_id) <= 0) {
perror("Could not get socket number or l3 id");
fclose(fp);
return -1;
}
fclose(fp);
return 0;
}
/*
* get_cache_size - Get cache size for a specified CPU
* @cpu_no: CPU number
* @cache_type: Cache level L2/L3
* @cache_size: pointer to cache_size
*
* Return: = 0 on success, < 0 on failure.
*/
int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size)
{
char cache_path[1024], cache_str[64];
int length, i, cache_num;
FILE *fp;
if (!strcmp(cache_type, "L3")) {
cache_num = 3;
} else if (!strcmp(cache_type, "L2")) {
cache_num = 2;
} else {
perror("Invalid cache level");
return -1;
}
sprintf(cache_path, "/sys/bus/cpu/devices/cpu%d/cache/index%d/size",
cpu_no, cache_num);
fp = fopen(cache_path, "r");
if (!fp) {
perror("Failed to open cache size");
return -1;
}
if (fscanf(fp, "%s", cache_str) <= 0) {
perror("Could not get cache_size");
fclose(fp);
return -1;
}
fclose(fp);
length = (int)strlen(cache_str);
*cache_size = 0;
for (i = 0; i < length; i++) {
if ((cache_str[i] >= '0') && (cache_str[i] <= '9'))
*cache_size = *cache_size * 10 + (cache_str[i] - '0');
else if (cache_str[i] == 'K')
*cache_size = *cache_size * 1024;
else if (cache_str[i] == 'M')
*cache_size = *cache_size * 1024 * 1024;
else
break;
}
return 0;
}
#define CORE_SIBLINGS_PATH "/sys/bus/cpu/devices/cpu"
/*
* get_cbm_mask - Get cbm mask for given cache
* @cache_type: Cache level L2/L3
* @cbm_mask: cbm_mask returned as a string
*
* Return: = 0 on success, < 0 on failure.
*/
int get_cbm_mask(char *cache_type, char *cbm_mask)
{
char cbm_mask_path[1024];
FILE *fp;
if (!cbm_mask)
return -1;
sprintf(cbm_mask_path, "%s/%s/cbm_mask", INFO_PATH, cache_type);
fp = fopen(cbm_mask_path, "r");
if (!fp) {
perror("Failed to open cache level");
return -1;
}
if (fscanf(fp, "%s", cbm_mask) <= 0) {
perror("Could not get max cbm_mask");
fclose(fp);
return -1;
}
fclose(fp);
return 0;
}
/*
* get_core_sibling - Get sibling core id from the same socket for given CPU
* @cpu_no: CPU number
*
* Return: > 0 on success, < 0 on failure.
*/
int get_core_sibling(int cpu_no)
{
char core_siblings_path[1024], cpu_list_str[64];
int sibling_cpu_no = -1;
FILE *fp;
sprintf(core_siblings_path, "%s%d/topology/core_siblings_list",
CORE_SIBLINGS_PATH, cpu_no);
fp = fopen(core_siblings_path, "r");
if (!fp) {
perror("Failed to open core siblings path");
return -1;
}
if (fscanf(fp, "%s", cpu_list_str) <= 0) {
perror("Could not get core_siblings list");
fclose(fp);
return -1;
}
fclose(fp);
char *token = strtok(cpu_list_str, "-,");
while (token) {
sibling_cpu_no = atoi(token);
/* Skipping core 0 as we don't want to run test on core 0 */
if (sibling_cpu_no != 0 && sibling_cpu_no != cpu_no)
break;
token = strtok(NULL, "-,");
}
return sibling_cpu_no;
}
/*
* taskset_benchmark - Taskset PID (i.e. benchmark) to a specified cpu
* @bm_pid: PID that should be binded
* @cpu_no: CPU number at which the PID would be binded
*
* Return: 0 on success, non-zero on failure
*/
int taskset_benchmark(pid_t bm_pid, int cpu_no)
{
cpu_set_t my_set;
CPU_ZERO(&my_set);
CPU_SET(cpu_no, &my_set);
if (sched_setaffinity(bm_pid, sizeof(cpu_set_t), &my_set)) {
perror("Unable to taskset benchmark");
return -1;
}
return 0;
}
/*
* create_grp - Create a group only if one doesn't exist
* @grp_name: Name of the group
* @grp: Full path and name of the group
* @parent_grp: Full path and name of the parent group
*
* Return: 0 on success, non-zero on failure
*/
static int create_grp(const char *grp_name, char *grp, const char *parent_grp)
{
int found_grp = 0;
struct dirent *ep;
DIR *dp;
/*
* At this point, we are guaranteed to have resctrl FS mounted and if
* length of grp_name == 0, it means, user wants to use root con_mon
* grp, so do nothing
*/
if (strlen(grp_name) == 0)
return 0;
/* Check if requested grp exists or not */
dp = opendir(parent_grp);
if (dp) {
while ((ep = readdir(dp)) != NULL) {
if (strcmp(ep->d_name, grp_name) == 0)
found_grp = 1;
}
closedir(dp);
} else {
perror("Unable to open resctrl for group");
return -1;
}
/* Requested grp doesn't exist, hence create it */
if (found_grp == 0) {
if (mkdir(grp, 0) == -1) {
perror("Unable to create group");
return -1;
}
}
return 0;
}
static int write_pid_to_tasks(char *tasks, pid_t pid)
{
FILE *fp;
fp = fopen(tasks, "w");
if (!fp) {
perror("Failed to open tasks file");
return -1;
}
if (fprintf(fp, "%d\n", pid) < 0) {
perror("Failed to wr pid to tasks file");
fclose(fp);
return -1;
}
fclose(fp);
return 0;
}
/*
* write_bm_pid_to_resctrl - Write a PID (i.e. benchmark) to resctrl FS
* @bm_pid: PID that should be written
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
* @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
*
* If a con_mon grp is requested, create it and write pid to it, otherwise
* write pid to root con_mon grp.
* If a mon grp is requested, create it and write pid to it, otherwise
* pid is not written, this means that pid is in con_mon grp and hence
* should consult con_mon grp's mon_data directory for results.
*
* Return: 0 on success, non-zero on failure
*/
int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
char *resctrl_val)
{
char controlgroup[128], monitorgroup[512], monitorgroup_p[256];
char tasks[1024];
int ret = 0;
if (strlen(ctrlgrp))
sprintf(controlgroup, "%s/%s", RESCTRL_PATH, ctrlgrp);
else
sprintf(controlgroup, "%s", RESCTRL_PATH);
/* Create control and monitoring group and write pid into it */
ret = create_grp(ctrlgrp, controlgroup, RESCTRL_PATH);
if (ret)
goto out;
sprintf(tasks, "%s/tasks", controlgroup);
ret = write_pid_to_tasks(tasks, bm_pid);
if (ret)
goto out;
/* Create mon grp and write pid into it for "mbm" and "cmt" test */
if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)) ||
!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
if (strlen(mongrp)) {
sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
ret = create_grp(mongrp, monitorgroup, monitorgroup_p);
if (ret)
goto out;
sprintf(tasks, "%s/mon_groups/%s/tasks",
controlgroup, mongrp);
ret = write_pid_to_tasks(tasks, bm_pid);
if (ret)
goto out;
}
}
out:
ksft_print_msg("Writing benchmark parameters to resctrl FS\n");
if (ret)
perror("# writing to resctrlfs");
return ret;
}
/*
* write_schemata - Update schemata of a con_mon grp
* @ctrlgrp: Name of the con_mon grp
* @schemata: Schemata that should be updated to
* @cpu_no: CPU number that the benchmark PID is binded to
* @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
*
* Update schemata of a con_mon grp *only* if requested resctrl feature is
* allocation type
*
* Return: 0 on success, non-zero on failure
*/
int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, char *resctrl_val)
{
char controlgroup[1024], reason[128], schema[1024] = {};
int resource_id, fd, schema_len = -1, ret = 0;
if (strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) &&
strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) &&
strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) &&
strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
return -ENOENT;
if (!schemata) {
ksft_print_msg("Skipping empty schemata update\n");
return -1;
}
if (get_resource_id(cpu_no, &resource_id) < 0) {
sprintf(reason, "Failed to get resource id");
ret = -1;
goto out;
}
if (strlen(ctrlgrp) != 0)
sprintf(controlgroup, "%s/%s/schemata", RESCTRL_PATH, ctrlgrp);
else
sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);
if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) ||
!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
schema_len = snprintf(schema, sizeof(schema), "%s%d%c%s\n",
"L3:", resource_id, '=', schemata);
if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
schema_len = snprintf(schema, sizeof(schema), "%s%d%c%s\n",
"MB:", resource_id, '=', schemata);
if (schema_len < 0 || schema_len >= sizeof(schema)) {
snprintf(reason, sizeof(reason),
"snprintf() failed with return value : %d", schema_len);
ret = -1;
goto out;
}
fd = open(controlgroup, O_WRONLY);
if (fd < 0) {
snprintf(reason, sizeof(reason),
"open() failed : %s", strerror(errno));
ret = -1;
goto err_schema_not_empty;
}
if (write(fd, schema, schema_len) < 0) {
snprintf(reason, sizeof(reason),
"write() failed : %s", strerror(errno));
close(fd);
ret = -1;
goto err_schema_not_empty;
}
close(fd);
err_schema_not_empty:
schema[schema_len - 1] = 0;
out:
ksft_print_msg("Write schema \"%s\" to resctrl FS%s%s\n",
schema, ret ? " # " : "",
ret ? reason : "");
return ret;
}
bool check_resctrlfs_support(void)
{
FILE *inf = fopen("/proc/filesystems", "r");
DIR *dp;
char *res;
bool ret = false;
if (!inf)
return false;
res = fgrep(inf, "nodev\tresctrl\n");
if (res) {
ret = true;
free(res);
}
fclose(inf);
ksft_print_msg("%s Check kernel supports resctrl filesystem\n",
ret ? "Pass:" : "Fail:");
if (!ret)
return ret;
dp = opendir(RESCTRL_PATH);
ksft_print_msg("%s Check resctrl mountpoint \"%s\" exists\n",
dp ? "Pass:" : "Fail:", RESCTRL_PATH);
if (dp)
closedir(dp);
ksft_print_msg("resctrl filesystem %s mounted\n",
find_resctrl_mount(NULL) ? "not" : "is");
return ret;
}
char *fgrep(FILE *inf, const char *str)
{
char line[256];
int slen = strlen(str);
while (!feof(inf)) {
if (!fgets(line, 256, inf))
break;
if (strncmp(line, str, slen))
continue;
return strdup(line);
}
return NULL;
}
/*
* validate_resctrl_feature_request - Check if requested feature is valid.
* @resource: Required resource (e.g., MB, L3, L2, L3_MON, etc.)
* @feature: Required monitor feature (in mon_features file). Can only be
* set for L3_MON. Must be NULL for all other resources.
*
* Return: True if the resource/feature is supported, else false. False is
* also returned if resctrl FS is not mounted.
*/
bool validate_resctrl_feature_request(const char *resource, const char *feature)
{
char res_path[PATH_MAX];
struct stat statbuf;
char *res;
FILE *inf;
int ret;
if (!resource)
return false;
ret = find_resctrl_mount(NULL);
if (ret)
return false;
snprintf(res_path, sizeof(res_path), "%s/%s", INFO_PATH, resource);
if (stat(res_path, &statbuf))
return false;
if (!feature)
return true;
snprintf(res_path, sizeof(res_path), "%s/%s/mon_features", INFO_PATH, resource);
inf = fopen(res_path, "r");
if (!inf)
return false;
res = fgrep(inf, feature);
free(res);
fclose(inf);
return !!res;
}
int filter_dmesg(void)
{
char line[1024];
FILE *fp;
int pipefds[2];
pid_t pid;
int ret;
ret = pipe(pipefds);
if (ret) {
perror("pipe");
return ret;
}
fflush(stdout);
pid = fork();
if (pid == 0) {
close(pipefds[0]);
dup2(pipefds[1], STDOUT_FILENO);
execlp("dmesg", "dmesg", NULL);
perror("executing dmesg");
exit(1);
}
close(pipefds[1]);
fp = fdopen(pipefds[0], "r");
if (!fp) {
perror("fdopen(pipe)");
kill(pid, SIGTERM);
return -1;
}
while (fgets(line, 1024, fp)) {
if (strstr(line, "intel_rdt:"))
ksft_print_msg("dmesg: %s", line);
if (strstr(line, "resctrl:"))
ksft_print_msg("dmesg: %s", line);
}
fclose(fp);
waitpid(pid, NULL, 0);
return 0;
}
int validate_bw_report_request(char *bw_report)
{
if (strcmp(bw_report, "reads") == 0)
return 0;
if (strcmp(bw_report, "writes") == 0)
return 0;
if (strcmp(bw_report, "nt-writes") == 0) {
strcpy(bw_report, "writes");
return 0;
}
if (strcmp(bw_report, "total") == 0)
return 0;
fprintf(stderr, "Requested iMC B/W report type unavailable\n");
return -1;
}
int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
int group_fd, unsigned long flags)
{
int ret;
ret = syscall(__NR_perf_event_open, hw_event, pid, cpu,
group_fd, flags);
return ret;
}
unsigned int count_bits(unsigned long n)
{
unsigned int count = 0;
while (n) {
count += n & 1;
n >>= 1;
}
return count;
}