blob: b32b96356ec70a79136b44b9d3b045894ba9c0b1 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Memory bandwidth monitoring and allocation library
*
* Copyright (C) 2018 Intel Corporation
*
* Authors:
* Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
* Fenghua Yu <fenghua.yu@intel.com>
*/
#include "resctrl.h"
#define UNCORE_IMC "uncore_imc"
#define READ_FILE_NAME "events/cas_count_read"
#define WRITE_FILE_NAME "events/cas_count_write"
#define DYN_PMU_PATH "/sys/bus/event_source/devices"
#define SCALE 0.00006103515625
#define MAX_IMCS 20
#define MAX_TOKENS 5
#define READ 0
#define WRITE 1
#define CON_MON_MBM_LOCAL_BYTES_PATH \
"%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
#define CON_MBM_LOCAL_BYTES_PATH \
"%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
#define MON_MBM_LOCAL_BYTES_PATH \
"%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
#define MBM_LOCAL_BYTES_PATH \
"%s/mon_data/mon_L3_%02d/mbm_local_bytes"
#define CON_MON_LCC_OCCUP_PATH \
"%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
#define CON_LCC_OCCUP_PATH \
"%s/%s/mon_data/mon_L3_%02d/llc_occupancy"
#define MON_LCC_OCCUP_PATH \
"%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
#define LCC_OCCUP_PATH \
"%s/mon_data/mon_L3_%02d/llc_occupancy"
struct membw_read_format {
__u64 value; /* The value of the event */
__u64 time_enabled; /* if PERF_FORMAT_TOTAL_TIME_ENABLED */
__u64 time_running; /* if PERF_FORMAT_TOTAL_TIME_RUNNING */
__u64 id; /* if PERF_FORMAT_ID */
};
struct imc_counter_config {
__u32 type;
__u64 event;
__u64 umask;
struct perf_event_attr pe;
struct membw_read_format return_value;
int fd;
};
static char mbm_total_path[1024];
static int imcs;
static struct imc_counter_config imc_counters_config[MAX_IMCS][2];
void membw_initialize_perf_event_attr(int i, int j)
{
memset(&imc_counters_config[i][j].pe, 0,
sizeof(struct perf_event_attr));
imc_counters_config[i][j].pe.type = imc_counters_config[i][j].type;
imc_counters_config[i][j].pe.size = sizeof(struct perf_event_attr);
imc_counters_config[i][j].pe.disabled = 1;
imc_counters_config[i][j].pe.inherit = 1;
imc_counters_config[i][j].pe.exclude_guest = 0;
imc_counters_config[i][j].pe.config =
imc_counters_config[i][j].umask << 8 |
imc_counters_config[i][j].event;
imc_counters_config[i][j].pe.sample_type = PERF_SAMPLE_IDENTIFIER;
imc_counters_config[i][j].pe.read_format =
PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING;
}
void membw_ioctl_perf_event_ioc_reset_enable(int i, int j)
{
ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_RESET, 0);
ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_ENABLE, 0);
}
void membw_ioctl_perf_event_ioc_disable(int i, int j)
{
ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_DISABLE, 0);
}
/*
* get_event_and_umask: Parse config into event and umask
* @cas_count_cfg: Config
* @count: iMC number
* @op: Operation (read/write)
*/
void get_event_and_umask(char *cas_count_cfg, int count, bool op)
{
char *token[MAX_TOKENS];
int i = 0;
strcat(cas_count_cfg, ",");
token[0] = strtok(cas_count_cfg, "=,");
for (i = 1; i < MAX_TOKENS; i++)
token[i] = strtok(NULL, "=,");
for (i = 0; i < MAX_TOKENS; i++) {
if (!token[i])
break;
if (strcmp(token[i], "event") == 0) {
if (op == READ)
imc_counters_config[count][READ].event =
strtol(token[i + 1], NULL, 16);
else
imc_counters_config[count][WRITE].event =
strtol(token[i + 1], NULL, 16);
}
if (strcmp(token[i], "umask") == 0) {
if (op == READ)
imc_counters_config[count][READ].umask =
strtol(token[i + 1], NULL, 16);
else
imc_counters_config[count][WRITE].umask =
strtol(token[i + 1], NULL, 16);
}
}
}
static int open_perf_event(int i, int cpu_no, int j)
{
imc_counters_config[i][j].fd =
perf_event_open(&imc_counters_config[i][j].pe, -1, cpu_no, -1,
PERF_FLAG_FD_CLOEXEC);
if (imc_counters_config[i][j].fd == -1) {
fprintf(stderr, "Error opening leader %llx\n",
imc_counters_config[i][j].pe.config);
return -1;
}
return 0;
}
/* Get type and config (read and write) of an iMC counter */
static int read_from_imc_dir(char *imc_dir, int count)
{
char cas_count_cfg[1024], imc_counter_cfg[1024], imc_counter_type[1024];
FILE *fp;
/* Get type of iMC counter */
sprintf(imc_counter_type, "%s%s", imc_dir, "type");
fp = fopen(imc_counter_type, "r");
if (!fp) {
perror("Failed to open imc counter type file");
return -1;
}
if (fscanf(fp, "%u", &imc_counters_config[count][READ].type) <= 0) {
perror("Could not get imc type");
fclose(fp);
return -1;
}
fclose(fp);
imc_counters_config[count][WRITE].type =
imc_counters_config[count][READ].type;
/* Get read config */
sprintf(imc_counter_cfg, "%s%s", imc_dir, READ_FILE_NAME);
fp = fopen(imc_counter_cfg, "r");
if (!fp) {
perror("Failed to open imc config file");
return -1;
}
if (fscanf(fp, "%s", cas_count_cfg) <= 0) {
perror("Could not get imc cas count read");
fclose(fp);
return -1;
}
fclose(fp);
get_event_and_umask(cas_count_cfg, count, READ);
/* Get write config */
sprintf(imc_counter_cfg, "%s%s", imc_dir, WRITE_FILE_NAME);
fp = fopen(imc_counter_cfg, "r");
if (!fp) {
perror("Failed to open imc config file");
return -1;
}
if (fscanf(fp, "%s", cas_count_cfg) <= 0) {
perror("Could not get imc cas count write");
fclose(fp);
return -1;
}
fclose(fp);
get_event_and_umask(cas_count_cfg, count, WRITE);
return 0;
}
/*
* A system can have 'n' number of iMC (Integrated Memory Controller)
* counters, get that 'n'. For each iMC counter get it's type and config.
* Also, each counter has two configs, one for read and the other for write.
* A config again has two parts, event and umask.
* Enumerate all these details into an array of structures.
*
* Return: >= 0 on success. < 0 on failure.
*/
static int num_of_imcs(void)
{
char imc_dir[512], *temp;
unsigned int count = 0;
struct dirent *ep;
int ret;
DIR *dp;
dp = opendir(DYN_PMU_PATH);
if (dp) {
while ((ep = readdir(dp))) {
temp = strstr(ep->d_name, UNCORE_IMC);
if (!temp)
continue;
/*
* imc counters are named as "uncore_imc_<n>", hence
* increment the pointer to point to <n>. Note that
* sizeof(UNCORE_IMC) would count for null character as
* well and hence the last underscore character in
* uncore_imc'_' need not be counted.
*/
temp = temp + sizeof(UNCORE_IMC);
/*
* Some directories under "DYN_PMU_PATH" could have
* names like "uncore_imc_free_running", hence, check if
* first character is a numerical digit or not.
*/
if (temp[0] >= '0' && temp[0] <= '9') {
sprintf(imc_dir, "%s/%s/", DYN_PMU_PATH,
ep->d_name);
ret = read_from_imc_dir(imc_dir, count);
if (ret) {
closedir(dp);
return ret;
}
count++;
}
}
closedir(dp);
if (count == 0) {
perror("Unable find iMC counters!\n");
return -1;
}
} else {
perror("Unable to open PMU directory!\n");
return -1;
}
return count;
}
static int initialize_mem_bw_imc(void)
{
int imc, j;
imcs = num_of_imcs();
if (imcs <= 0)
return imcs;
/* Initialize perf_event_attr structures for all iMC's */
for (imc = 0; imc < imcs; imc++) {
for (j = 0; j < 2; j++)
membw_initialize_perf_event_attr(imc, j);
}
return 0;
}
/*
* get_mem_bw_imc: Memory band width as reported by iMC counters
* @cpu_no: CPU number that the benchmark PID is binded to
* @bw_report: Bandwidth report type (reads, writes)
*
* Memory B/W utilized by a process on a socket can be calculated using
* iMC counters. Perf events are used to read these counters.
*
* Return: = 0 on success. < 0 on failure.
*/
static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
{
float reads, writes, of_mul_read, of_mul_write;
int imc, j, ret;
/* Start all iMC counters to log values (both read and write) */
reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
for (imc = 0; imc < imcs; imc++) {
for (j = 0; j < 2; j++) {
ret = open_perf_event(imc, cpu_no, j);
if (ret)
return -1;
}
for (j = 0; j < 2; j++)
membw_ioctl_perf_event_ioc_reset_enable(imc, j);
}
sleep(1);
/* Stop counters after a second to get results (both read and write) */
for (imc = 0; imc < imcs; imc++) {
for (j = 0; j < 2; j++)
membw_ioctl_perf_event_ioc_disable(imc, j);
}
/*
* Get results which are stored in struct type imc_counter_config
* Take over flow into consideration before calculating total b/w
*/
for (imc = 0; imc < imcs; imc++) {
struct imc_counter_config *r =
&imc_counters_config[imc][READ];
struct imc_counter_config *w =
&imc_counters_config[imc][WRITE];
if (read(r->fd, &r->return_value,
sizeof(struct membw_read_format)) == -1) {
perror("Couldn't get read b/w through iMC");
return -1;
}
if (read(w->fd, &w->return_value,
sizeof(struct membw_read_format)) == -1) {
perror("Couldn't get write bw through iMC");
return -1;
}
__u64 r_time_enabled = r->return_value.time_enabled;
__u64 r_time_running = r->return_value.time_running;
if (r_time_enabled != r_time_running)
of_mul_read = (float)r_time_enabled /
(float)r_time_running;
__u64 w_time_enabled = w->return_value.time_enabled;
__u64 w_time_running = w->return_value.time_running;
if (w_time_enabled != w_time_running)
of_mul_write = (float)w_time_enabled /
(float)w_time_running;
reads += r->return_value.value * of_mul_read * SCALE;
writes += w->return_value.value * of_mul_write * SCALE;
}
for (imc = 0; imc < imcs; imc++) {
close(imc_counters_config[imc][READ].fd);
close(imc_counters_config[imc][WRITE].fd);
}
if (strcmp(bw_report, "reads") == 0) {
*bw_imc = reads;
return 0;
}
if (strcmp(bw_report, "writes") == 0) {
*bw_imc = writes;
return 0;
}
*bw_imc = reads + writes;
return 0;
}
void set_mbm_path(const char *ctrlgrp, const char *mongrp, int resource_id)
{
if (ctrlgrp && mongrp)
sprintf(mbm_total_path, CON_MON_MBM_LOCAL_BYTES_PATH,
RESCTRL_PATH, ctrlgrp, mongrp, resource_id);
else if (!ctrlgrp && mongrp)
sprintf(mbm_total_path, MON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
mongrp, resource_id);
else if (ctrlgrp && !mongrp)
sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
ctrlgrp, resource_id);
else if (!ctrlgrp && !mongrp)
sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
resource_id);
}
/*
* initialize_mem_bw_resctrl: Appropriately populate "mbm_total_path"
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
* @cpu_no: CPU number that the benchmark PID is binded to
* @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
*/
static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
int cpu_no, char *resctrl_val)
{
int resource_id;
if (get_resource_id(cpu_no, &resource_id) < 0) {
perror("Could not get resource_id");
return;
}
if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
set_mbm_path(ctrlgrp, mongrp, resource_id);
if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
if (ctrlgrp)
sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH,
RESCTRL_PATH, ctrlgrp, resource_id);
else
sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH,
RESCTRL_PATH, resource_id);
}
}
/*
* Get MBM Local bytes as reported by resctrl FS
* For MBM,
* 1. If con_mon grp and mon grp are given, then read from con_mon grp's mon grp
* 2. If only con_mon grp is given, then read from con_mon grp
* 3. If both are not given, then read from root con_mon grp
* For MBA,
* 1. If con_mon grp is given, then read from it
* 2. If con_mon grp is not given, then read from root con_mon grp
*/
static int get_mem_bw_resctrl(unsigned long *mbm_total)
{
FILE *fp;
fp = fopen(mbm_total_path, "r");
if (!fp) {
perror("Failed to open total bw file");
return -1;
}
if (fscanf(fp, "%lu", mbm_total) <= 0) {
perror("Could not get mbm local bytes");
fclose(fp);
return -1;
}
fclose(fp);
return 0;
}
pid_t bm_pid, ppid;
void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
{
kill(bm_pid, SIGKILL);
umount_resctrlfs();
tests_cleanup();
ksft_print_msg("Ending\n\n");
exit(EXIT_SUCCESS);
}
/*
* print_results_bw: the memory bandwidth results are stored in a file
* @filename: file that stores the results
* @bm_pid: child pid that runs benchmark
* @bw_imc: perf imc counter value
* @bw_resc: memory bandwidth value
*
* Return: 0 on success. non-zero on failure.
*/
static int print_results_bw(char *filename, int bm_pid, float bw_imc,
unsigned long bw_resc)
{
unsigned long diff = fabs(bw_imc - bw_resc);
FILE *fp;
if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
printf("Pid: %d \t Mem_BW_iMC: %f \t ", bm_pid, bw_imc);
printf("Mem_BW_resc: %lu \t Difference: %lu\n", bw_resc, diff);
} else {
fp = fopen(filename, "a");
if (!fp) {
perror("Cannot open results file");
return errno;
}
if (fprintf(fp, "Pid: %d \t Mem_BW_iMC: %f \t Mem_BW_resc: %lu \t Difference: %lu\n",
bm_pid, bw_imc, bw_resc, diff) <= 0) {
fclose(fp);
perror("Could not log results.");
return errno;
}
fclose(fp);
}
return 0;
}
static void set_cmt_path(const char *ctrlgrp, const char *mongrp, char sock_num)
{
if (strlen(ctrlgrp) && strlen(mongrp))
sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
ctrlgrp, mongrp, sock_num);
else if (!strlen(ctrlgrp) && strlen(mongrp))
sprintf(llc_occup_path, MON_LCC_OCCUP_PATH, RESCTRL_PATH,
mongrp, sock_num);
else if (strlen(ctrlgrp) && !strlen(mongrp))
sprintf(llc_occup_path, CON_LCC_OCCUP_PATH, RESCTRL_PATH,
ctrlgrp, sock_num);
else if (!strlen(ctrlgrp) && !strlen(mongrp))
sprintf(llc_occup_path, LCC_OCCUP_PATH, RESCTRL_PATH, sock_num);
}
/*
* initialize_llc_occu_resctrl: Appropriately populate "llc_occup_path"
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
* @cpu_no: CPU number that the benchmark PID is binded to
* @resctrl_val: Resctrl feature (Eg: cat, cmt.. etc)
*/
static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
int cpu_no, char *resctrl_val)
{
int resource_id;
if (get_resource_id(cpu_no, &resource_id) < 0) {
perror("# Unable to resource_id");
return;
}
if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
set_cmt_path(ctrlgrp, mongrp, resource_id);
}
static int
measure_vals(struct resctrl_val_param *param, unsigned long *bw_resc_start)
{
unsigned long bw_resc, bw_resc_end;
float bw_imc;
int ret;
/*
* Measure memory bandwidth from resctrl and from
* another source which is perf imc value or could
* be something else if perf imc event is not available.
* Compare the two values to validate resctrl value.
* It takes 1sec to measure the data.
*/
ret = get_mem_bw_imc(param->cpu_no, param->bw_report, &bw_imc);
if (ret < 0)
return ret;
ret = get_mem_bw_resctrl(&bw_resc_end);
if (ret < 0)
return ret;
bw_resc = (bw_resc_end - *bw_resc_start) / MB;
ret = print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
if (ret)
return ret;
*bw_resc_start = bw_resc_end;
return 0;
}
/*
* resctrl_val: execute benchmark and measure memory bandwidth on
* the benchmark
* @benchmark_cmd: benchmark command and its arguments
* @param: parameters passed to resctrl_val()
*
* Return: 0 on success. non-zero on failure.
*/
int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param)
{
char *resctrl_val = param->resctrl_val;
unsigned long bw_resc_start = 0;
struct sigaction sigact;
int ret = 0, pipefd[2];
char pipe_message = 0;
union sigval value;
if (strcmp(param->filename, "") == 0)
sprintf(param->filename, "stdio");
if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
ret = validate_bw_report_request(param->bw_report);
if (ret)
return ret;
}
ret = remount_resctrlfs(param->mum_resctrlfs);
if (ret)
return ret;
/*
* If benchmark wasn't successfully started by child, then child should
* kill parent, so save parent's pid
*/
ppid = getpid();
if (pipe(pipefd)) {
perror("# Unable to create pipe");
return -1;
}
/*
* Fork to start benchmark, save child's pid so that it can be killed
* when needed
*/
bm_pid = fork();
if (bm_pid == -1) {
perror("# Unable to fork");
return -1;
}
if (bm_pid == 0) {
/*
* Mask all signals except SIGUSR1, parent uses SIGUSR1 to
* start benchmark
*/
sigfillset(&sigact.sa_mask);
sigdelset(&sigact.sa_mask, SIGUSR1);
sigact.sa_sigaction = run_benchmark;
sigact.sa_flags = SA_SIGINFO;
/* Register for "SIGUSR1" signal from parent */
if (sigaction(SIGUSR1, &sigact, NULL))
PARENT_EXIT("Can't register child for signal");
/* Tell parent that child is ready */
close(pipefd[0]);
pipe_message = 1;
if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
sizeof(pipe_message)) {
perror("# failed signaling parent process");
close(pipefd[1]);
return -1;
}
close(pipefd[1]);
/* Suspend child until delivery of "SIGUSR1" from parent */
sigsuspend(&sigact.sa_mask);
PARENT_EXIT("Child is done");
}
ksft_print_msg("Benchmark PID: %d\n", bm_pid);
/*
* Register CTRL-C handler for parent, as it has to kill benchmark
* before exiting
*/
sigact.sa_sigaction = ctrlc_handler;
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = SA_SIGINFO;
if (sigaction(SIGINT, &sigact, NULL) ||
sigaction(SIGTERM, &sigact, NULL) ||
sigaction(SIGHUP, &sigact, NULL)) {
perror("# sigaction");
ret = errno;
goto out;
}
value.sival_ptr = benchmark_cmd;
/* Taskset benchmark to specified cpu */
ret = taskset_benchmark(bm_pid, param->cpu_no);
if (ret)
goto out;
/* Write benchmark to specified control&monitoring grp in resctrl FS */
ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
resctrl_val);
if (ret)
goto out;
if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
ret = initialize_mem_bw_imc();
if (ret)
goto out;
initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
param->cpu_no, resctrl_val);
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
param->cpu_no, resctrl_val);
/* Parent waits for child to be ready. */
close(pipefd[1]);
while (pipe_message != 1) {
if (read(pipefd[0], &pipe_message, sizeof(pipe_message)) <
sizeof(pipe_message)) {
perror("# failed reading message from child process");
close(pipefd[0]);
goto out;
}
}
close(pipefd[0]);
/* Signal child to start benchmark */
if (sigqueue(bm_pid, SIGUSR1, value) == -1) {
perror("# sigqueue SIGUSR1 to child");
ret = errno;
goto out;
}
/* Give benchmark enough time to fully run */
sleep(1);
/* Test runs until the callback setup() tells the test to stop. */
while (1) {
if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
ret = param->setup(1, param);
if (ret) {
ret = 0;
break;
}
ret = measure_vals(param, &bw_resc_start);
if (ret)
break;
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
ret = param->setup(1, param);
if (ret) {
ret = 0;
break;
}
sleep(1);
ret = measure_cache_vals(param, bm_pid);
if (ret)
break;
} else {
break;
}
}
out:
kill(bm_pid, SIGKILL);
umount_resctrlfs();
return ret;
}