1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Memory Bandwidth Allocation (MBA) 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
 13#define RESULT_FILE_NAME	"result_mba"
 14#define NUM_OF_RUNS		5
 15#define MAX_DIFF_PERCENT	5
 16#define ALLOCATION_MAX		100
 17#define ALLOCATION_MIN		10
 18#define ALLOCATION_STEP		10
 19
 20/*
 21 * Change schemata percentage from 100 to 10%. Write schemata to specified
 22 * con_mon grp, mon_grp in resctrl FS.
 23 * For each allocation, run 5 times in order to get average values.
 24 */
 25static int mba_setup(int num, ...)
 26{
 27	static int runs_per_allocation, allocation = 100;
 28	struct resctrl_val_param *p;
 29	char allocation_str[64];
 30	va_list param;
 31
 32	va_start(param, num);
 33	p = va_arg(param, struct resctrl_val_param *);
 34	va_end(param);
 35
 36	if (runs_per_allocation >= NUM_OF_RUNS)
 37		runs_per_allocation = 0;
 38
 39	/* Only set up schemata once every NUM_OF_RUNS of allocations */
 40	if (runs_per_allocation++ != 0)
 41		return 0;
 42
 43	if (allocation < ALLOCATION_MIN || allocation > ALLOCATION_MAX)
 44		return -1;
 45
 46	sprintf(allocation_str, "%d", allocation);
 47
 48	write_schemata(p->ctrlgrp, allocation_str, p->cpu_no, p->resctrl_val);
 49	allocation -= ALLOCATION_STEP;
 50
 51	return 0;
 52}
 53
 54static void show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
 55{
 56	int allocation, runs;
 57	bool failed = false;
 58
 59	ksft_print_msg("Results are displayed in (MB)\n");
 60	/* Memory bandwidth from 100% down to 10% */
 61	for (allocation = 0; allocation < ALLOCATION_MAX / ALLOCATION_STEP;
 62	     allocation++) {
 63		unsigned long avg_bw_imc, avg_bw_resc;
 64		unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
 65		int avg_diff_per;
 66		float avg_diff;
 67
 68		/*
 69		 * The first run is discarded due to inaccurate value from
 70		 * phase transition.
 71		 */
 72		for (runs = NUM_OF_RUNS * allocation + 1;
 73		     runs < NUM_OF_RUNS * allocation + NUM_OF_RUNS ; runs++) {
 74			sum_bw_imc += bw_imc[runs];
 75			sum_bw_resc += bw_resc[runs];
 76		}
 77
 78		avg_bw_imc = sum_bw_imc / (NUM_OF_RUNS - 1);
 79		avg_bw_resc = sum_bw_resc / (NUM_OF_RUNS - 1);
 80		avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;
 81		avg_diff_per = (int)(avg_diff * 100);
 82
 83		ksft_print_msg("%s Check MBA diff within %d%% for schemata %u\n",
 84			       avg_diff_per > MAX_DIFF_PERCENT ?
 85			       "Fail:" : "Pass:",
 86			       MAX_DIFF_PERCENT,
 87			       ALLOCATION_MAX - ALLOCATION_STEP * allocation);
 88
 89		ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);
 90		ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
 91		ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
 92		if (avg_diff_per > MAX_DIFF_PERCENT)
 93			failed = true;
 94	}
 95
 96	ksft_print_msg("%s Check schemata change using MBA\n",
 97		       failed ? "Fail:" : "Pass:");
 98	if (failed)
 99		ksft_print_msg("At least one test failed\n");
100}
101
102static int check_results(void)
103{
104	char *token_array[8], output[] = RESULT_FILE_NAME, temp[512];
105	unsigned long bw_imc[1024], bw_resc[1024];
106	int runs;
107	FILE *fp;
108
109	fp = fopen(output, "r");
110	if (!fp) {
111		perror(output);
112
113		return errno;
114	}
115
116	runs = 0;
117	while (fgets(temp, sizeof(temp), fp)) {
118		char *token = strtok(temp, ":\t");
119		int fields = 0;
120
121		while (token) {
122			token_array[fields++] = token;
123			token = strtok(NULL, ":\t");
124		}
125
126		/* Field 3 is perf imc value */
127		bw_imc[runs] = strtoul(token_array[3], NULL, 0);
128		/* Field 5 is resctrl value */
129		bw_resc[runs] = strtoul(token_array[5], NULL, 0);
130		runs++;
131	}
132
133	fclose(fp);
134
135	show_mba_info(bw_imc, bw_resc);
136
137	return 0;
138}
139
140void mba_test_cleanup(void)
141{
142	remove(RESULT_FILE_NAME);
143}
144
145int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd)
146{
147	struct resctrl_val_param param = {
148		.resctrl_val	= MBA_STR,
149		.ctrlgrp	= "c1",
150		.mongrp		= "m1",
151		.cpu_no		= cpu_no,
152		.mum_resctrlfs	= 1,
153		.filename	= RESULT_FILE_NAME,
154		.bw_report	= bw_report,
155		.setup		= mba_setup
156	};
157	int ret;
158
159	remove(RESULT_FILE_NAME);
160
161	ret = resctrl_val(benchmark_cmd, &param);
162	if (ret)
163		return ret;
164
165	ret = check_results();
166	if (ret)
167		return ret;
168
169	mba_test_cleanup();
170
171	return 0;
172}