// SPDX-License-Identifier: GPL-2.0
/*
 * Cache Monitoring Technology (CMT) 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_NAME        "result_cmt"
#define NUM_OF_RUNS             5
#define MAX_DIFF                2000000
#define MAX_DIFF_PERCENT        15

#define CON_MON_LCC_OCCUP_PATH          \
        "%s/%s/mon_data/mon_L3_%02d/llc_occupancy"

static int cmt_init(const struct resctrl_val_param *param, int domain_id)
{
        sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
                param->ctrlgrp, domain_id);

        return 0;
}

static int cmt_setup(const struct resctrl_test *test,
                     const struct user_params *uparams,
                     struct resctrl_val_param *p)
{
        /* Run NUM_OF_RUNS times */
        if (p->num_of_runs >= NUM_OF_RUNS)
                return END_OF_TESTS;

        p->num_of_runs++;

        return 0;
}

static int cmt_measure(const struct user_params *uparams,
                       struct resctrl_val_param *param, pid_t bm_pid)
{
        sleep(1);
        return measure_llc_resctrl(param->filename, bm_pid);
}

static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
                             unsigned long cache_span, unsigned long max_diff,
                             unsigned long max_diff_percent, unsigned long num_of_runs,
                             bool platform)
{
        unsigned long avg_llc_val = 0;
        float diff_percent;
        long avg_diff = 0;
        int ret;

        avg_llc_val = sum_llc_val / num_of_runs;
        avg_diff = (long)(cache_span - avg_llc_val);
        diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100;

        ret = platform && abs((int)diff_percent) > max_diff_percent &&
              labs(avg_diff) > max_diff;

        ksft_print_msg("%s Check cache miss rate within %lu%%\n",
                       ret ? "Fail:" : "Pass:", max_diff_percent);

        ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));

        show_cache_info(no_of_bits, avg_llc_val, cache_span, false);

        return ret;
}

static int check_results(struct resctrl_val_param *param, size_t span, int no_of_bits)
{
        char *token_array[8], temp[512];
        unsigned long sum_llc_occu_resc = 0;
        int runs = 0;
        FILE *fp;

        ksft_print_msg("Checking for pass/fail\n");
        fp = fopen(param->filename, "r");
        if (!fp) {
                ksft_perror("Error in opening file");

                return -1;
        }

        while (fgets(temp, sizeof(temp), fp)) {
                char *token = strtok(temp, ":\t");
                int fields = 0;

                while (token) {
                        token_array[fields++] = token;
                        token = strtok(NULL, ":\t");
                }

                /* Field 3 is llc occ resc value */
                sum_llc_occu_resc += strtoul(token_array[3], NULL, 0);
                runs++;
        }
        fclose(fp);

        return show_results_info(sum_llc_occu_resc, no_of_bits, span,
                                 MAX_DIFF, MAX_DIFF_PERCENT, runs, true);
}

static void cmt_test_cleanup(void)
{
        remove(RESULT_FILE_NAME);
}

static int cmt_run_test(const struct resctrl_test *test, const struct user_params *uparams)
{
        struct fill_buf_param fill_buf = {};
        unsigned long cache_total_size = 0;
        int n = uparams->bits ? : 5;
        unsigned long long_mask;
        int count_of_bits;
        size_t span;
        int ret;

        ret = get_full_cbm("L3", &long_mask);
        if (ret)
                return ret;

        ret = get_cache_size(uparams->cpu, "L3", &cache_total_size);
        if (ret)
                return ret;
        ksft_print_msg("Cache size :%lu\n", cache_total_size);

        count_of_bits = count_bits(long_mask);

        if (n < 1 || n > count_of_bits) {
                ksft_print_msg("Invalid input value for numbr_of_bits n!\n");
                ksft_print_msg("Please enter value in range 1 to %d\n", count_of_bits);
                return -1;
        }

        struct resctrl_val_param param = {
                .ctrlgrp        = "c1",
                .filename       = RESULT_FILE_NAME,
                .mask           = ~(long_mask << n) & long_mask,
                .num_of_runs    = 0,
                .init           = cmt_init,
                .setup          = cmt_setup,
                .measure        = cmt_measure,
        };

        span = cache_portion_size(cache_total_size, param.mask, long_mask);

        if (uparams->fill_buf) {
                fill_buf.buf_size = span;
                fill_buf.memflush = uparams->fill_buf->memflush;
                param.fill_buf = &fill_buf;
        } else if (!uparams->benchmark_cmd[0]) {
                fill_buf.buf_size = span;
                fill_buf.memflush = true;
                param.fill_buf = &fill_buf;
        }

        remove(RESULT_FILE_NAME);

        ret = resctrl_val(test, uparams, &param);
        if (ret)
                return ret;

        ret = check_results(&param, span, n);
        if (ret && (get_vendor() == ARCH_INTEL) && !snc_kernel_support())
                ksft_print_msg("Kernel doesn't support Sub-NUMA Clustering but it is enabled on the system.\n");

        return ret;
}

static bool cmt_feature_check(const struct resctrl_test *test)
{
        return test_resource_feature_check(test) &&
               resctrl_mon_feature_exists("L3_MON", "llc_occupancy");
}

struct resctrl_test cmt_test = {
        .name = "CMT",
        .resource = "L3",
        .feature_check = cmt_feature_check,
        .run_test = cmt_run_test,
        .cleanup = cmt_test_cleanup,
};