// SPDX-License-Identifier: GPL-2.0
/*
 * Resctrl tests
 *
 * Copyright (C) 2018 Intel Corporation
 *
 * Authors:
 *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
 *    Fenghua Yu <fenghua.yu@intel.com>
 */
#include "resctrl.h"

/* Volatile memory sink to prevent compiler optimizations */
static volatile int sink_target;
volatile int *value_sink = &sink_target;

static struct resctrl_test *resctrl_tests[] = {
        &mbm_test,
        &mba_test,
        &cmt_test,
        &l3_cat_test,
        &l3_noncont_cat_test,
        &l2_noncont_cat_test,
};

static unsigned int detect_vendor(void)
{
        static unsigned int vendor_id;
        static bool initialized;
        char *s = NULL;
        FILE *inf;
        char *res;

        if (initialized)
                return vendor_id;

        inf = fopen("/proc/cpuinfo", "r");
        if (!inf) {
                vendor_id = 0;
                initialized = true;
                return vendor_id;
        }

        res = fgrep(inf, "vendor_id");

        if (res)
                s = strchr(res, ':');

        if (s && !strcmp(s, ": GenuineIntel\n"))
                vendor_id = ARCH_INTEL;
        else if (s && !strcmp(s, ": AuthenticAMD\n"))
                vendor_id = ARCH_AMD;
        else if (s && !strcmp(s, ": HygonGenuine\n"))
                vendor_id = ARCH_HYGON;

        fclose(inf);
        free(res);

        initialized = true;
        return vendor_id;
}

unsigned int get_vendor(void)
{
        unsigned int vendor;

        vendor = detect_vendor();

        if (vendor == 0)
                ksft_print_msg("Can not get vendor info...\n");

        return vendor;
}

static void cmd_help(void)
{
        int i;

        printf("usage: resctrl_tests [-h] [-t test list] [-n no_of_bits] [-b benchmark_cmd [option]...]\n");
        printf("\t-b benchmark_cmd [option]...: run specified benchmark for MBM, MBA and CMT\n");
        printf("\t   default benchmark is builtin fill_buf\n");
        printf("\t-t test list: run tests/groups specified by the list, ");
        printf("e.g. -t mbm,mba,cmt,cat\n");
        printf("\t\tSupported tests (group):\n");
        for (i = 0; i < ARRAY_SIZE(resctrl_tests); i++) {
                if (resctrl_tests[i]->group)
                        printf("\t\t\t%s (%s)\n", resctrl_tests[i]->name, resctrl_tests[i]->group);
                else
                        printf("\t\t\t%s\n", resctrl_tests[i]->name);
        }
        printf("\t-n no_of_bits: run cache tests using specified no of bits in cache bit mask\n");
        printf("\t-p cpu_no: specify CPU number to run the test. 1 is default\n");
        printf("\t-h: help\n");
}

static int test_prepare(const struct resctrl_test *test)
{
        int res;

        res = signal_handler_register(test);
        if (res) {
                ksft_print_msg("Failed to register signal handler\n");
                return res;
        }

        res = mount_resctrlfs();
        if (res) {
                signal_handler_unregister();
                ksft_print_msg("Failed to mount resctrl FS\n");
                return res;
        }
        return 0;
}

static void test_cleanup(const struct resctrl_test *test)
{
        if (test->cleanup)
                test->cleanup();
        umount_resctrlfs();
        signal_handler_unregister();
}

static bool test_vendor_specific_check(const struct resctrl_test *test)
{
        if (!test->vendor_specific)
                return true;

        return get_vendor() & test->vendor_specific;
}

static void run_single_test(const struct resctrl_test *test, const struct user_params *uparams)
{
        int ret, snc_mode;

        if (test->disabled)
                return;

        if (!test_vendor_specific_check(test)) {
                ksft_test_result_skip("Hardware does not support %s\n", test->name);
                return;
        }

        snc_mode = snc_nodes_per_l3_cache();

        ksft_print_msg("Starting %s test ...\n", test->name);

        if (snc_mode == 1 && snc_unreliable && get_vendor() == ARCH_INTEL) {
                ksft_test_result_skip("SNC detection unreliable due to offline CPUs. Test results may not be accurate if SNC enabled.\n");
                return;
        }

        if (test_prepare(test)) {
                ksft_exit_fail_msg("Abnormal failure when preparing for the test\n");
                return;
        }

        if (!test->feature_check(test)) {
                ksft_test_result_skip("Hardware does not support %s or %s is disabled\n",
                                      test->name, test->name);
                goto cleanup;
        }

        ret = test->run_test(test, uparams);
        ksft_test_result(!ret, "%s: test\n", test->name);

cleanup:
        test_cleanup(test);
}

/*
 * Allocate and initialize a struct fill_buf_param with user provided
 * (via "-b fill_buf <fill_buf parameters>") parameters.
 *
 * Use defaults (that may not be appropriate for all tests) for any
 * fill_buf parameters omitted by the user.
 *
 * Historically it may have been possible for user space to provide
 * additional parameters, "operation" ("read" vs "write") in
 * benchmark_cmd[3] and "once" (run "once" or until terminated) in
 * benchmark_cmd[4]. Changing these parameters have never been
 * supported with the default of "read" operation and running until
 * terminated built into the tests. Any unsupported values for
 * (original) "fill_buf" parameters are treated as failure.
 *
 * Return: On failure, forcibly exits the test on any parsing failure,
 *         returns NULL if no parsing needed (user did not actually provide
 *         "-b fill_buf").
 *         On success, returns pointer to newly allocated and fully
 *         initialized struct fill_buf_param that caller must free.
 */
static struct fill_buf_param *alloc_fill_buf_param(struct user_params *uparams)
{
        struct fill_buf_param *fill_param = NULL;
        char *endptr = NULL;

        if (!uparams->benchmark_cmd[0] || strcmp(uparams->benchmark_cmd[0], "fill_buf"))
                return NULL;

        fill_param = malloc(sizeof(*fill_param));
        if (!fill_param)
                ksft_exit_skip("Unable to allocate memory for fill_buf parameters.\n");

        if (uparams->benchmark_cmd[1] && *uparams->benchmark_cmd[1] != '\0') {
                errno = 0;
                fill_param->buf_size = strtoul(uparams->benchmark_cmd[1], &endptr, 10);
                if (errno || *endptr != '\0') {
                        free(fill_param);
                        ksft_exit_skip("Unable to parse benchmark buffer size.\n");
                }
        } else {
                fill_param->buf_size = MINIMUM_SPAN;
        }

        if (uparams->benchmark_cmd[2] && *uparams->benchmark_cmd[2] != '\0') {
                errno = 0;
                fill_param->memflush = strtol(uparams->benchmark_cmd[2], &endptr, 10) != 0;
                if (errno || *endptr != '\0') {
                        free(fill_param);
                        ksft_exit_skip("Unable to parse benchmark memflush parameter.\n");
                }
        } else {
                fill_param->memflush = true;
        }

        if (uparams->benchmark_cmd[3] && *uparams->benchmark_cmd[3] != '\0') {
                if (strcmp(uparams->benchmark_cmd[3], "0")) {
                        free(fill_param);
                        ksft_exit_skip("Only read operations supported.\n");
                }
        }

        if (uparams->benchmark_cmd[4] && *uparams->benchmark_cmd[4] != '\0') {
                if (strcmp(uparams->benchmark_cmd[4], "false")) {
                        free(fill_param);
                        ksft_exit_skip("fill_buf is required to run until termination.\n");
                }
        }

        return fill_param;
}

static void init_user_params(struct user_params *uparams)
{
        memset(uparams, 0, sizeof(*uparams));

        uparams->cpu = 1;
        uparams->bits = 0;
}

int main(int argc, char **argv)
{
        struct fill_buf_param *fill_param = NULL;
        int tests = ARRAY_SIZE(resctrl_tests);
        bool test_param_seen = false;
        struct user_params uparams;
        int c, i;

        init_user_params(&uparams);

        while ((c = getopt(argc, argv, "ht:b:n:p:")) != -1) {
                char *token;

                switch (c) {
                case 'b':
                        /*
                         * First move optind back to the (first) optarg and
                         * then build the benchmark command using the
                         * remaining arguments.
                         */
                        optind--;
                        if (argc - optind >= BENCHMARK_ARGS)
                                ksft_exit_fail_msg("Too long benchmark command");

                        /* Extract benchmark command from command line. */
                        for (i = 0; i < argc - optind; i++)
                                uparams.benchmark_cmd[i] = argv[i + optind];
                        uparams.benchmark_cmd[i] = NULL;

                        goto last_arg;
                case 't':
                        token = strtok(optarg, ",");

                        if (!test_param_seen) {
                                for (i = 0; i < ARRAY_SIZE(resctrl_tests); i++)
                                        resctrl_tests[i]->disabled = true;
                                tests = 0;
                                test_param_seen = true;
                        }
                        while (token) {
                                bool found = false;

                                for (i = 0; i < ARRAY_SIZE(resctrl_tests); i++) {
                                        if (!strcasecmp(token, resctrl_tests[i]->name) ||
                                            (resctrl_tests[i]->group &&
                                             !strcasecmp(token, resctrl_tests[i]->group))) {
                                                if (resctrl_tests[i]->disabled)
                                                        tests++;
                                                resctrl_tests[i]->disabled = false;
                                                found = true;
                                        }
                                }

                                if (!found) {
                                        printf("invalid test: %s\n", token);

                                        return -1;
                                }
                                token = strtok(NULL, ",");
                        }
                        break;
                case 'p':
                        uparams.cpu = atoi(optarg);
                        break;
                case 'n':
                        uparams.bits = atoi(optarg);
                        if (uparams.bits <= 0) {
                                printf("Bail out! invalid argument for no_of_bits\n");
                                return -1;
                        }
                        break;
                case 'h':
                        cmd_help();

                        return 0;
                default:
                        printf("invalid argument\n");

                        return -1;
                }
        }
last_arg:

        fill_param = alloc_fill_buf_param(&uparams);
        if (fill_param)
                uparams.fill_buf = fill_param;

        ksft_print_header();

        /*
         * Typically we need root privileges, because:
         * 1. We write to resctrl FS
         * 2. We execute perf commands
         */
        if (geteuid() != 0)
                ksft_exit_skip("Not running as root. Skipping...\n");

        if (!check_resctrlfs_support())
                ksft_exit_skip("resctrl FS does not exist. Enable X86_CPU_RESCTRL config option.\n");

        if (umount_resctrlfs())
                ksft_exit_skip("resctrl FS unmount failed.\n");

        filter_dmesg();

        ksft_set_plan(tests);

        for (i = 0; i < ARRAY_SIZE(resctrl_tests); i++)
                run_single_test(resctrl_tests[i], &uparams);

        free(fill_param);
        ksft_finished();
}