Re: [PATCH v7 06/13] selftests/resctrl: Add MBM test
From: Andre Przywara
Date: Fri May 10 2019 - 13:38:57 EST
On Sat, 9 Feb 2019 18:50:35 -0800
Fenghua Yu <fenghua.yu@xxxxxxxxx> wrote:
Hi,
> From: Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pathan@xxxxxxxxx>
>
> MBM (Memory Bandwidth Monitoring) test is the first implemented selftest.
> It starts a stressful memory bandwidth benchmark and assigns the
> bandwidth pid in a resctrl monitoring group. Read and compare perf IMC
> counter and MBM total bytes for the benchmark. The numbers should be
> close enough to pass the test.
>
> Default benchmark is built-in fill_buf. But users can specify their
> own benchmark by option "-b".
>
> We can add memory bandwidth monitoring for multiple processes in the
> future.
>
> Signed-off-by: Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pathan@xxxxxxxxx>
> Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@xxxxxxxxx>,
> Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> ---
> tools/testing/selftests/resctrl/Makefile | 8 +-
> tools/testing/selftests/resctrl/mbm_test.c | 149 ++++++++++++++++++++++++
> tools/testing/selftests/resctrl/resctrl.h | 3 +
> tools/testing/selftests/resctrl/resctrl_tests.c | 114 ++++++++++++++++++
> tools/testing/selftests/resctrl/resctrl_val.c | 2 +
> 5 files changed, 275 insertions(+), 1 deletion(-)
> create mode 100644 tools/testing/selftests/resctrl/mbm_test.c
> create mode 100644 tools/testing/selftests/resctrl/resctrl_tests.c
>
> diff --git a/tools/testing/selftests/resctrl/Makefile b/tools/testing/selftests/resctrl/Makefile
> index bd5c5418961e..eaa8b45de10d 100644
> --- a/tools/testing/selftests/resctrl/Makefile
> +++ b/tools/testing/selftests/resctrl/Makefile
> @@ -1,10 +1,16 @@
> CC = gcc
> CFLAGS = -g -Wall
>
> +all: resctrl_tests
> +
> *.o: *.c
> $(CC) $(CFLAGS) -c *.c
>
> +resctrl_tests: *.o
> + $(CC) $(CFLAGS) -o resctrl_tests resctrl_tests.o resctrlfs.o \
> + resctrl_val.o fill_buf.o mbm_test.o
This is a somewhat non-standard way of specifying things in a Makefile.
What about:
OBJS = resctrl_tests.o resctrlfs.o resctrl_val.o fill_buf.o mbm_test.o
resctrl_tests: $(OBJS)
$(CC) $(LDFLAGS) -o $@ $^
> +
> .PHONY: clean
>
> clean:
> - $(RM) *.o *~
> + $(RM) *.o *~ resctrl_tests
> diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
> new file mode 100644
> index 000000000000..dba981c562ff
> --- /dev/null
> +++ b/tools/testing/selftests/resctrl/mbm_test.c
> @@ -0,0 +1,149 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Memory Bandwidth Monitoring (MBM) test
> + *
> + * Copyright (C) 2018 Intel Corporation
> + *
> + * Authors:
> + * Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pathan@xxxxxxxxx>
> + * Sai Praneeth Prakhya <sai.praneeth.prakhya@xxxxxxxxx>,
> + * Fenghua Yu <fenghua.yu@xxxxxxxxx>
> + */
> +#include "resctrl.h"
> +
> +#define RESULT_FILE_NAME "result_mbm"
> +#define MAX_DIFF 300
What is that value? 300 MB/s? Is that some heuristic? Shouldn't that be
relative, like in the other benchmarks?
> +#define NUM_OF_RUNS 5
> +
> +static void
> +show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, int span)
> +{
> + unsigned long avg_bw_imc = 0, avg_bw_resc = 0;
Why do you initialise those if they are overwritten below?
> + unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
> + long avg_diff = 0;
Same here.
> + int runs;
> +
> + /*
> + * Discard the first value which is inaccurate due to monitoring setup
> + * transition phase.
> + */
> + for (runs = 1; runs < NUM_OF_RUNS ; runs++) {
> + sum_bw_imc += bw_imc[runs];
> + sum_bw_resc += bw_resc[runs];
> + }
> +
> + avg_bw_imc = sum_bw_imc / 4;
> + avg_bw_resc = sum_bw_resc / 4;
> + avg_diff = avg_bw_resc - avg_bw_imc;
You could make avg_diff unsigned and use the labs() call already here.
Cheers,
Andre.
> +
> + printf("\nSpan (MB): %d \t", span);
> + printf("avg_bw_imc: %lu\t", avg_bw_imc);
> + printf("avg_bw_resc: %lu\t", avg_bw_resc);
> + printf("avg_diff: %lu\t", labs(avg_diff));
> +
> + if (labs(avg_diff) > MAX_DIFF)
> + printf(" failed\n");
> + else
> + printf(" passed\n");
> +}
> +
> +static int check_results(int span)
> +{
> + unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS];
> + char temp[1024], *token_array[8];
> + char output[] = RESULT_FILE_NAME;
> + int runs;
> + FILE *fp;
> +
> + printf("\nChecking for pass/fail\n");
> +
> + fp = fopen(output, "r");
> + if (!fp) {
> + perror("Error in opening file\n");
> +
> + return errno;
> + }
> +
> + runs = 0;
> + while (fgets(temp, 1024, fp)) {
> + char *token = strtok(temp, ":\t");
> + int i = 0;
> +
> + while (token) {
> + token_array[i++] = token;
> + token = strtok(NULL, ":\t");
> + }
> +
> + bw_resc[runs] = strtoul(token_array[5], NULL, 0);
> + bw_imc[runs] = strtoul(token_array[3], NULL, 0);
> + runs++;
> + }
> +
> + show_bw_info(bw_imc, bw_resc, span);
> +
> + fclose(fp);
> +
> + return 0;
> +}
> +
> +static int mbm_setup(int num, ...)
> +{
> + struct resctrl_val_param *p;
> + static int num_of_runs;
> + va_list param;
> + int ret = 0;
> +
> + /* Run NUM_OF_RUNS times */
> + if (num_of_runs++ >= NUM_OF_RUNS)
> + return -1;
> +
> + va_start(param, num);
> + p = va_arg(param, struct resctrl_val_param *);
> + va_end(param);
> +
> + /* Set up shemata with 100% allocation on the first run. */
> + if (num_of_runs == 0)
> + ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
> + p->resctrl_val);
> +
> + return ret;
> +}
> +
> +void mbm_test_cleanup(void)
> +{
> + remove(RESULT_FILE_NAME);
> +}
> +
> +int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
> +{
> + struct resctrl_val_param param = {
> + .resctrl_val = "mbm",
> + .ctrlgrp = "c1",
> + .mongrp = "m1",
> + .span = span,
> + .cpu_no = cpu_no,
> + .mum_resctrlfs = 1,
> + .filename = RESULT_FILE_NAME,
> + .bw_report = bw_report,
> + .setup = mbm_setup
> + };
> + int ret;
> +
> + remove(RESULT_FILE_NAME);
> +
> + ret = validate_resctrl_feature_request("mbm");
> + if (ret)
> + return ret;
> +
> + ret = resctrl_val(benchmark_cmd, ¶m);
> + if (ret)
> + return ret;
> +
> + ret = check_results(span);
> + if (ret)
> + return ret;
> +
> + mbm_test_cleanup();
> +
> + return 0;
> +}
> diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
> index c286790ba24d..7f7ea180478c 100644
> --- a/tools/testing/selftests/resctrl/resctrl.h
> +++ b/tools/testing/selftests/resctrl/resctrl.h
> @@ -71,5 +71,8 @@ int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
> int run_fill_buf(unsigned long span, int malloc_and_init_memory, int memflush,
> int op, char *resctrl_va);
> int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param);
> +int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd);
> +void tests_cleanup(void);
> +void mbm_test_cleanup(void);
>
> #endif /* RESCTRL_H */
> diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
> new file mode 100644
> index 000000000000..a51780d28ff1
> --- /dev/null
> +++ b/tools/testing/selftests/resctrl/resctrl_tests.c
> @@ -0,0 +1,114 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Resctrl tests
> + *
> + * Copyright (C) 2018 Intel Corporation
> + *
> + * Authors:
> + * Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pathan@xxxxxxxxx>
> + * Sai Praneeth Prakhya <sai.praneeth.prakhya@xxxxxxxxx>,
> + * Fenghua Yu <fenghua.yu@xxxxxxxxx>
> + */
> +#include "resctrl.h"
> +
> +#define BENCHMARK_ARGS 64
> +#define BENCHMARK_ARG_SIZE 64
> +
> +static void cmd_help(void)
> +{
> + printf("usage: resctrl_tests [-h] [-b \"benchmark_cmd [options]\"] [-t test list]\n");
> + printf("\t-b benchmark_cmd [options]: run specified benchmark\n");
> + printf("\t default benchmark is builtin fill_buf\n");
> + printf("\t-t test list: run tests specified in the test list, ");
> + printf("e.g. -t mbm,mba\n");
> + printf("\t-h: help\n");
> +}
> +
> +void tests_cleanup(void)
> +{
> + mbm_test_cleanup();
> +}
> +
> +int main(int argc, char **argv)
> +{
> + char benchmark_cmd_area[BENCHMARK_ARGS][BENCHMARK_ARG_SIZE];
> + int res, c, cpu_no = 1, span = 250, argc_new = argc, i;
> + int ben_ind;
> + bool has_ben = false, mbm_test = true;
> + char *benchmark_cmd[BENCHMARK_ARGS];
> + char bw_report[64], bm_type[64];
> +
> + for (i = 0; i < argc; i++) {
> + if (strcmp(argv[i], "-b") == 0) {
> + ben_ind = i + 1;
> + argc_new = ben_ind - 1;
> + has_ben = 1;
> + break;
> + }
> + }
> +
> + while ((c = getopt(argc_new, argv, "ht:b:")) != -1) {
> + char *token;
> +
> + switch (c) {
> + case 't':
> + token = strtok(optarg, ",");
> +
> + mbm_test = false;
> + while (token) {
> + if (!strcmp(token, "mbm")) {
> + mbm_test = true;
> + } else {
> + printf("invalid argument\n");
> +
> + return -1;
> + }
> + token = strtok(NULL, ":\t");
> + }
> + break;
> + case 'h':
> + cmd_help();
> +
> + return 0;
> + default:
> + printf("invalid argument\n");
> +
> + return -1;
> + }
> + }
> +
> + /*
> + * We need root privileges to run because
> + * 1. We write to resctrl FS
> + * 2. We execute perf commands
> + */
> + if (geteuid() != 0) {
> + perror("Please run this program as root\n");
> +
> + return errno;
> + }
> +
> + if (!has_ben) {
> + /* If no benchmark is given by "-b" argument, use fill_buf. */
> + for (i = 0; i < 5; i++)
> + benchmark_cmd[i] = benchmark_cmd_area[i];
> + strcpy(benchmark_cmd[0], "fill_buf");
> + sprintf(benchmark_cmd[1], "%d", span);
> + strcpy(benchmark_cmd[2], "1");
> + strcpy(benchmark_cmd[3], "1");
> + strcpy(benchmark_cmd[4], "0");
> + benchmark_cmd[5] = NULL;
> + }
> +
> + sprintf(bw_report, "reads");
> + sprintf(bm_type, "fill_buf");
> +
> + if (mbm_test) {
> + printf("\nMBM BW Change Starting..\n");
> + res = mbm_bw_change(span, cpu_no, bw_report, benchmark_cmd);
> + if (res)
> + printf("Error in running tests for mbm bw change!\n");
> + }
> +
> + return 0;
> +}
> diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
> index 43c15e382892..200a5b6756da 100644
> --- a/tools/testing/selftests/resctrl/resctrl_val.c
> +++ b/tools/testing/selftests/resctrl/resctrl_val.c
> @@ -437,6 +437,8 @@ pid_t bm_pid, ppid;
> static void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
> {
> kill(bm_pid, SIGKILL);
> + umount_resctrlfs();
> + tests_cleanup();
> printf("Ending\n\n");
>
> exit(EXIT_SUCCESS);