cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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cat_test.c (5031B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Cache Allocation Technology (CAT) test
      4 *
      5 * Copyright (C) 2018 Intel Corporation
      6 *
      7 * Authors:
      8 *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
      9 *    Fenghua Yu <fenghua.yu@intel.com>
     10 */
     11#include "resctrl.h"
     12#include <unistd.h>
     13
     14#define RESULT_FILE_NAME1	"result_cat1"
     15#define RESULT_FILE_NAME2	"result_cat2"
     16#define NUM_OF_RUNS		5
     17#define MAX_DIFF_PERCENT	4
     18#define MAX_DIFF		1000000
     19
     20static int count_of_bits;
     21static char cbm_mask[256];
     22static unsigned long long_mask;
     23static unsigned long cache_size;
     24
     25/*
     26 * Change schemata. Write schemata to specified
     27 * con_mon grp, mon_grp in resctrl FS.
     28 * Run 5 times in order to get average values.
     29 */
     30static int cat_setup(int num, ...)
     31{
     32	struct resctrl_val_param *p;
     33	char schemata[64];
     34	va_list param;
     35	int ret = 0;
     36
     37	va_start(param, num);
     38	p = va_arg(param, struct resctrl_val_param *);
     39	va_end(param);
     40
     41	/* Run NUM_OF_RUNS times */
     42	if (p->num_of_runs >= NUM_OF_RUNS)
     43		return -1;
     44
     45	if (p->num_of_runs == 0) {
     46		sprintf(schemata, "%lx", p->mask);
     47		ret = write_schemata(p->ctrlgrp, schemata, p->cpu_no,
     48				     p->resctrl_val);
     49	}
     50	p->num_of_runs++;
     51
     52	return ret;
     53}
     54
     55static int check_results(struct resctrl_val_param *param)
     56{
     57	char *token_array[8], temp[512];
     58	unsigned long sum_llc_perf_miss = 0;
     59	int runs = 0, no_of_bits = 0;
     60	FILE *fp;
     61
     62	ksft_print_msg("Checking for pass/fail\n");
     63	fp = fopen(param->filename, "r");
     64	if (!fp) {
     65		perror("# Cannot open file");
     66
     67		return errno;
     68	}
     69
     70	while (fgets(temp, sizeof(temp), fp)) {
     71		char *token = strtok(temp, ":\t");
     72		int fields = 0;
     73
     74		while (token) {
     75			token_array[fields++] = token;
     76			token = strtok(NULL, ":\t");
     77		}
     78		/*
     79		 * Discard the first value which is inaccurate due to monitoring
     80		 * setup transition phase.
     81		 */
     82		if (runs > 0)
     83			sum_llc_perf_miss += strtoul(token_array[3], NULL, 0);
     84		runs++;
     85	}
     86
     87	fclose(fp);
     88	no_of_bits = count_bits(param->mask);
     89
     90	return show_cache_info(sum_llc_perf_miss, no_of_bits, param->span / 64,
     91			       MAX_DIFF, MAX_DIFF_PERCENT, NUM_OF_RUNS,
     92			       get_vendor() == ARCH_INTEL, false);
     93}
     94
     95void cat_test_cleanup(void)
     96{
     97	remove(RESULT_FILE_NAME1);
     98	remove(RESULT_FILE_NAME2);
     99}
    100
    101int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
    102{
    103	unsigned long l_mask, l_mask_1;
    104	int ret, pipefd[2], sibling_cpu_no;
    105	char pipe_message;
    106	pid_t bm_pid;
    107
    108	cache_size = 0;
    109
    110	ret = remount_resctrlfs(true);
    111	if (ret)
    112		return ret;
    113
    114	/* Get default cbm mask for L3/L2 cache */
    115	ret = get_cbm_mask(cache_type, cbm_mask);
    116	if (ret)
    117		return ret;
    118
    119	long_mask = strtoul(cbm_mask, NULL, 16);
    120
    121	/* Get L3/L2 cache size */
    122	ret = get_cache_size(cpu_no, cache_type, &cache_size);
    123	if (ret)
    124		return ret;
    125	ksft_print_msg("Cache size :%lu\n", cache_size);
    126
    127	/* Get max number of bits from default-cabm mask */
    128	count_of_bits = count_bits(long_mask);
    129
    130	if (!n)
    131		n = count_of_bits / 2;
    132
    133	if (n > count_of_bits - 1) {
    134		ksft_print_msg("Invalid input value for no_of_bits n!\n");
    135		ksft_print_msg("Please enter value in range 1 to %d\n",
    136			       count_of_bits - 1);
    137		return -1;
    138	}
    139
    140	/* Get core id from same socket for running another thread */
    141	sibling_cpu_no = get_core_sibling(cpu_no);
    142	if (sibling_cpu_no < 0)
    143		return -1;
    144
    145	struct resctrl_val_param param = {
    146		.resctrl_val	= CAT_STR,
    147		.cpu_no		= cpu_no,
    148		.mum_resctrlfs	= 0,
    149		.setup		= cat_setup,
    150	};
    151
    152	l_mask = long_mask >> n;
    153	l_mask_1 = ~l_mask & long_mask;
    154
    155	/* Set param values for parent thread which will be allocated bitmask
    156	 * with (max_bits - n) bits
    157	 */
    158	param.span = cache_size * (count_of_bits - n) / count_of_bits;
    159	strcpy(param.ctrlgrp, "c2");
    160	strcpy(param.mongrp, "m2");
    161	strcpy(param.filename, RESULT_FILE_NAME2);
    162	param.mask = l_mask;
    163	param.num_of_runs = 0;
    164
    165	if (pipe(pipefd)) {
    166		perror("# Unable to create pipe");
    167		return errno;
    168	}
    169
    170	bm_pid = fork();
    171
    172	/* Set param values for child thread which will be allocated bitmask
    173	 * with n bits
    174	 */
    175	if (bm_pid == 0) {
    176		param.mask = l_mask_1;
    177		strcpy(param.ctrlgrp, "c1");
    178		strcpy(param.mongrp, "m1");
    179		param.span = cache_size * n / count_of_bits;
    180		strcpy(param.filename, RESULT_FILE_NAME1);
    181		param.num_of_runs = 0;
    182		param.cpu_no = sibling_cpu_no;
    183	}
    184
    185	remove(param.filename);
    186
    187	ret = cat_val(&param);
    188	if (ret)
    189		return ret;
    190
    191	ret = check_results(&param);
    192	if (ret)
    193		return ret;
    194
    195	if (bm_pid == 0) {
    196		/* Tell parent that child is ready */
    197		close(pipefd[0]);
    198		pipe_message = 1;
    199		if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
    200		    sizeof(pipe_message)) {
    201			close(pipefd[1]);
    202			perror("# failed signaling parent process");
    203			return errno;
    204		}
    205
    206		close(pipefd[1]);
    207		while (1)
    208			;
    209	} else {
    210		/* Parent waits for child to be ready. */
    211		close(pipefd[1]);
    212		pipe_message = 0;
    213		while (pipe_message != 1) {
    214			if (read(pipefd[0], &pipe_message,
    215				 sizeof(pipe_message)) < sizeof(pipe_message)) {
    216				perror("# failed reading from child process");
    217				break;
    218			}
    219		}
    220		close(pipefd[0]);
    221		kill(bm_pid, SIGKILL);
    222	}
    223
    224	cat_test_cleanup();
    225	if (bm_pid)
    226		umount_resctrlfs();
    227
    228	return 0;
    229}