blob: 20823725daca5bcb0d769e08ffef5888a7bac4f4 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Cache Allocation Technology (CAT) test
*
* Copyright (C) 2018 Intel Corporation
*
* Authors:
* Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
* Fenghua Yu <fenghua.yu@intel.com>
*/
#include "resctrl.h"
#include <unistd.h>
#define RESULT_FILE_NAME1 "result_cat1"
#define RESULT_FILE_NAME2 "result_cat2"
#define NUM_OF_RUNS 5
#define MAX_DIFF_PERCENT 4
#define MAX_DIFF 1000000
static int count_of_bits;
static char cbm_mask[256];
static unsigned long long_mask;
static unsigned long cache_size;
/*
* Change schemata. Write schemata to specified
* con_mon grp, mon_grp in resctrl FS.
* Run 5 times in order to get average values.
*/
static int cat_setup(int num, ...)
{
struct resctrl_val_param *p;
char schemata[64];
va_list param;
int ret = 0;
va_start(param, num);
p = va_arg(param, struct resctrl_val_param *);
va_end(param);
/* Run NUM_OF_RUNS times */
if (p->num_of_runs >= NUM_OF_RUNS)
return -1;
if (p->num_of_runs == 0) {
sprintf(schemata, "%lx", p->mask);
ret = write_schemata(p->ctrlgrp, schemata, p->cpu_no,
p->resctrl_val);
}
p->num_of_runs++;
return ret;
}
static void show_cache_info(unsigned long sum_llc_perf_miss, int no_of_bits,
unsigned long span)
{
unsigned long allocated_cache_lines = span / 64;
unsigned long avg_llc_perf_miss = 0;
float diff_percent;
avg_llc_perf_miss = sum_llc_perf_miss / (NUM_OF_RUNS - 1);
diff_percent = ((float)allocated_cache_lines - avg_llc_perf_miss) /
allocated_cache_lines * 100;
printf("%sok CAT: cache miss rate within %d%%\n",
!is_amd && abs((int)diff_percent) > MAX_DIFF_PERCENT ?
"not " : "", MAX_DIFF_PERCENT);
tests_run++;
printf("# Percent diff=%d\n", abs((int)diff_percent));
printf("# Number of bits: %d\n", no_of_bits);
printf("# Avg_llc_perf_miss: %lu\n", avg_llc_perf_miss);
printf("# Allocated cache lines: %lu\n", allocated_cache_lines);
}
static int check_results(struct resctrl_val_param *param)
{
char *token_array[8], temp[512];
unsigned long sum_llc_perf_miss = 0;
int runs = 0, no_of_bits = 0;
FILE *fp;
printf("# Checking for pass/fail\n");
fp = fopen(param->filename, "r");
if (!fp) {
perror("# Cannot open file");
return errno;
}
while (fgets(temp, sizeof(temp), fp)) {
char *token = strtok(temp, ":\t");
int fields = 0;
while (token) {
token_array[fields++] = token;
token = strtok(NULL, ":\t");
}
/*
* Discard the first value which is inaccurate due to monitoring
* setup transition phase.
*/
if (runs > 0)
sum_llc_perf_miss += strtoul(token_array[3], NULL, 0);
runs++;
}
fclose(fp);
no_of_bits = count_bits(param->mask);
show_cache_info(sum_llc_perf_miss, no_of_bits, param->span);
return 0;
}
void cat_test_cleanup(void)
{
remove(RESULT_FILE_NAME1);
remove(RESULT_FILE_NAME2);
}
int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
{
unsigned long l_mask, l_mask_1;
int ret, pipefd[2], sibling_cpu_no;
char pipe_message;
pid_t bm_pid;
cache_size = 0;
ret = remount_resctrlfs(true);
if (ret)
return ret;
if (!validate_resctrl_feature_request("cat"))
return -1;
/* Get default cbm mask for L3/L2 cache */
ret = get_cbm_mask(cache_type, cbm_mask);
if (ret)
return ret;
long_mask = strtoul(cbm_mask, NULL, 16);
/* Get L3/L2 cache size */
ret = get_cache_size(cpu_no, cache_type, &cache_size);
if (ret)
return ret;
printf("cache size :%lu\n", cache_size);
/* Get max number of bits from default-cabm mask */
count_of_bits = count_bits(long_mask);
if (n < 1 || n > count_of_bits - 1) {
printf("Invalid input value for no_of_bits n!\n");
printf("Please Enter value in range 1 to %d\n",
count_of_bits - 1);
return -1;
}
/* Get core id from same socket for running another thread */
sibling_cpu_no = get_core_sibling(cpu_no);
if (sibling_cpu_no < 0)
return -1;
struct resctrl_val_param param = {
.resctrl_val = CAT_STR,
.cpu_no = cpu_no,
.mum_resctrlfs = 0,
.setup = cat_setup,
};
l_mask = long_mask >> n;
l_mask_1 = ~l_mask & long_mask;
/* Set param values for parent thread which will be allocated bitmask
* with (max_bits - n) bits
*/
param.span = cache_size * (count_of_bits - n) / count_of_bits;
strcpy(param.ctrlgrp, "c2");
strcpy(param.mongrp, "m2");
strcpy(param.filename, RESULT_FILE_NAME2);
param.mask = l_mask;
param.num_of_runs = 0;
if (pipe(pipefd)) {
perror("# Unable to create pipe");
return errno;
}
bm_pid = fork();
/* Set param values for child thread which will be allocated bitmask
* with n bits
*/
if (bm_pid == 0) {
param.mask = l_mask_1;
strcpy(param.ctrlgrp, "c1");
strcpy(param.mongrp, "m1");
param.span = cache_size * n / count_of_bits;
strcpy(param.filename, RESULT_FILE_NAME1);
param.num_of_runs = 0;
param.cpu_no = sibling_cpu_no;
}
remove(param.filename);
ret = cat_val(&param);
if (ret)
return ret;
ret = check_results(&param);
if (ret)
return ret;
if (bm_pid == 0) {
/* Tell parent that child is ready */
close(pipefd[0]);
pipe_message = 1;
if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
sizeof(pipe_message)) {
close(pipefd[1]);
perror("# failed signaling parent process");
return errno;
}
close(pipefd[1]);
while (1)
;
} else {
/* Parent waits for child to be ready. */
close(pipefd[1]);
pipe_message = 0;
while (pipe_message != 1) {
if (read(pipefd[0], &pipe_message,
sizeof(pipe_message)) < sizeof(pipe_message)) {
perror("# failed reading from child process");
break;
}
}
close(pipefd[0]);
kill(bm_pid, SIGKILL);
}
cat_test_cleanup();
if (bm_pid)
umount_resctrlfs();
return 0;
}