From: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com>
The callback starts a child process and puts the child pid in created
resctrl group with specified memory bandwidth in schemata. The child
starts running benchmark.
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com>
Signed-off-by: Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pat...@intel.com>
Signed-off-by: Fenghua Yu <fenghua...@intel.com>
---
tools/testing/selftests/resctrl/membw.c | 273 ++++++++++++++++++++++++++++++
tools/testing/selftests/resctrl/resctrl.h | 27 +++
2 files changed, 300 insertions(+)
diff --git a/tools/testing/selftests/resctrl/membw.c
b/tools/testing/selftests/resctrl/membw.c
index 1bced7e7f148..dfcd9c1244d8 100644
--- a/tools/testing/selftests/resctrl/membw.c
+++ b/tools/testing/selftests/resctrl/membw.c
@@ -401,3 +401,276 @@ static unsigned long get_mem_bw_resctrl(void)
return mbm_total;
}
+
+pid_t bm_pid, ppid;
+
+static void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
+{
+ kill(bm_pid, SIGKILL);
+ printf("Ending\n\n");
+
+ exit(EXIT_SUCCESS);
+}
+
+/*
+ * print_results_bw: the memory bandwidth results are stored in a file
+ * @filename: file that stores the results
+ * @bm_pid: child pid that runs benchmark
+ * @bw_imc: perf imc counter value
+ * @bw_resc: memory bandwidth value
+ *
+ * Return: 0 on success. non-zero on failure.
+ */
+static int print_results_bw(char *filename, int bm_pid, float bw_imc,
+ unsigned long bw_resc)
+{
+ int diff = abs(bw_imc - bw_resc);
+ FILE *fp;
+
+ if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
+ printf("Pid: %d \t Mem_BW_iMC: %f \t ", bm_pid, bw_imc);
+ printf("Mem_BW_resc: %lu \t Difference: %d\n", bw_resc, diff);
+ } else {
+ fp = fopen(filename, "a");
+ if (!fp) {
+ perror("Cannot open results file");
+
+ return errno;
+ }
+ if (fprintf(fp, "Pid: %d \t Mem_BW_iMC: %f \t ",
+ bm_pid, bw_imc) <= 0 ||
+ fprintf(fp, "Mem_BW_resc: %lu \t Difference: %d\n",
+ bw_resc, diff) <= 0) {
+ fclose(fp);
+ perror("Could not log results.");
+
+ return errno;
+ }
+ fclose(fp);
+ }
+
+ return 0;
+}
+
+static int
+measure_vals(struct resctrl_val_param *param, unsigned long *bw_resc_start)
+{
+ unsigned long bw_imc, bw_resc, bw_resc_end;
+ int ret;
+
+ /*
+ * Measure memory bandwidth from resctrl and from
+ * another source which is perf imc value or could
+ * be something else if perf imc event is not available.
+ * Compare the two values to validate resctrl value.
+ * It takes 1sec to measure the data.
+ */
+ bw_imc = get_mem_bw_imc(param->cpu_no, param->bw_report);
+ if (bw_imc < 0)
+ return bw_imc;
+
+ bw_resc_end = get_mem_bw_resctrl();
+ if (bw_resc_end < 0)
+ return bw_resc_end;
+
+ bw_resc = (bw_resc_end - *bw_resc_start) / MB;
+ ret = print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
+ if (ret)
+ return ret;
+
+ *bw_resc_start = bw_resc_end;
+
+ return 0;
+}
+
+/*
+ * membw_val: execute benchmark and measure memory bandwidth on
+ * the benchmark
+ * @benchmark_cmd: benchmark command and its arguments
+ * @param: parameters passed to membw_val()
+ *
+ * Return: 0 on success. non-zero on failure.
+ */
+int membw_val(char **benchmark_cmd, struct resctrl_val_param *param)
+{
+ char *resctrl_val = param->resctrl_val;
+ unsigned long bw_resc_start = 0;
+ struct sigaction sigact;
+ union sigval value;
+ int sig = 0, ret = 0;
+ FILE *fp;
+
+ if (strcmp(param->filename, "") == 0)
+ sprintf(param->filename, "stdio");
+
+ if (strcmp(param->bw_report, "") == 0)
+ param->bw_report = "total";
+
+ ret = validate_resctrl_feature_request(resctrl_val);
+ if (ret)
+ return ret;
+
+ if ((strcmp(resctrl_val, "mba")) == 0 ||
+ (strcmp(resctrl_val, "mbm")) == 0) {
+ ret = validate_bw_report_request(param->bw_report);
+ if (ret)
+ return ret;
+ }
+
+ ret = remount_resctrlfs(param->mum_resctrlfs);
+ if (ret)
+ return ret;
+
+ /*
+ * If benchmark wasn't successfully started by child, then child should
+ * kill parent, so save parent's pid
+ */
+ ppid = getpid();
+
+ /* File based synchronization between parent and child */
+ fp = fopen("sig", "w");
+ if (!fp || (fprintf(fp, "%d\n", 0) <= 0) || (fclose(fp) == EOF)) {
+ perror("Unable to establish sync bw parent & child");
+
+ return errno;
+ }
+
+ /*
+ * Fork to start benchmark, save child's pid so that it can be killed
+ * when needed
+ */
+ bm_pid = fork();
+ if (bm_pid == -1) {
+ perror("Unable to fork");
+
+ return errno;
+ }
+
+ if (bm_pid == 0) {
+ /*
+ * Mask all signals except SIGUSR1, parent uses SIGUSR1 to
+ * start benchmark
+ */
+ sigfillset(&sigact.sa_mask);
+ sigdelset(&sigact.sa_mask, SIGUSR1);
+
+ sigact.sa_sigaction = run_benchmark;
+ sigact.sa_flags = SA_SIGINFO;
+
+ /* Register for "SIGUSR1" signal from parent */
+ if (sigaction(SIGUSR1, &sigact, NULL))
+ PARENT_EXIT("Can't register child for signal");
+
+ /* Signal parent that child is ready */
+ fp = fopen("sig", "w");
+ if (!fp || (fprintf(fp, "%d\n", 1) <= 0) ||
+ (fclose(fp) == EOF))
+ PARENT_EXIT("can't signal that child is ready");
+
+ /* Suspend child until delivery of "SIGUSR1" from parent */
+ sigsuspend(&sigact.sa_mask);
+ }
+
+ printf("Benchmark PID: %d\n", bm_pid);
+
+ /*
+ * Register CTRL-C handler for parent, as it has to kill benchmark
+ * before exiting
+ */
+ sigact.sa_sigaction = ctrlc_handler;
+ sigemptyset(&sigact.sa_mask);
+ sigact.sa_flags = SA_SIGINFO;
+ if (sigaction(SIGINT, &sigact, NULL) ||
+ sigaction(SIGHUP, &sigact, NULL)) {
+ perror("Can't register parent for CTRL-C handler");
+ ret = errno;
+ goto out;
+ }
+
+ value.sival_ptr = benchmark_cmd;
+
+ /* Taskset benchmark to specified cpu */
+ ret = taskset_benchmark(bm_pid, param->cpu_no);
+ if (ret)
+ goto out;
+
+ /* Write benchmark to specified con_mon grp, mon_grp in resctrl FS*/
+ ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
+ resctrl_val);
+ if (ret)
+ goto out;
+
+ if ((strcmp(resctrl_val, "mbm") == 0) ||
+ (strcmp(resctrl_val, "mba") == 0)) {
+ ret = initialize_mem_bw_imc();
+ if (ret)
+ goto out;
+
+ initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
+ param->cpu_no, resctrl_val);
+ }
+
+ /*
+ * Parent should signal child to start executing benchmark only upon
+ * receiving a signal from child saying that it's ready
+ */
+ while (sig == 0) {
+ fp = fopen("sig", "r");
+ if (!fp) {
+ perror("Unable to open 'sig' file");
+ ret = errno;
+ goto out;
+ }
+ fscanf(fp, "%d\n", &sig);
+ if (fclose(fp) == EOF) {
+ perror("Unable to close 'sig' file");
+ ret = errno;
+ goto out;
+ }
+ }
+ if (system(RM_SIG_FILE) != 0)
+ perror("Unable to remove 'sig' file");
+
+ /* Signal child to start benchmark */
+ if (sigqueue(bm_pid, SIGUSR1, value) == -1) {
+ perror("Unable to signal child to start execution");
+ ret = errno;
+ goto out;
+ }
+
+ /* Give benchmark enough time to fully run */
+ sleep(1);
+
+ /* Test runs until the callback setup() tells the test to stop. */
+ while (1) {
+ if (strcmp(resctrl_val, "mbm") == 0) {
+ ret = param->setup(1, param);
+ if (ret) {
+ ret = 0;
+ break;
+ }
+
+ ret = measure_vals(param, &bw_resc_start);
+ if (ret)
+ break;
+ } else if ((strcmp(resctrl_val, "mba") == 0)) {
+ ret = param->setup(1, param->cpu_no);
+ if (ret) {
+ ret = 0;
+ break;
+ }
+
+ ret = measure_vals(param, &bw_resc_start);
+ if (ret)
+ break;
+ } else {
+ break;
+ }
+ }
+
+out:
+ kill(bm_pid, SIGKILL);
+ umount_resctrlfs();
+
+ return ret;
+}
diff --git a/tools/testing/selftests/resctrl/resctrl.h
b/tools/testing/selftests/resctrl/resctrl.h
index fe3c3434df97..f1de2dee8f50 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -3,6 +3,7 @@
#ifndef RESCTRL_H
#define RESCTRL_H
#include <stdio.h>
+#include <stdarg.h>
#include <errno.h>
#include <sched.h>
#include <stdlib.h>
@@ -33,10 +34,35 @@
exit(EXIT_FAILURE); \
} while (0)
+/*
+ * resctrl_val_param: resctrl test parameters
+ * @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
+ * @ctrlgrp: Name of the control monitor group (con_mon grp)
+ * @mongrp: Name of the monitor group (mon grp)
+ * @cpu_no: CPU number to which the benchmark would be binded
+ * @mum_resctrlfs: Should the resctrl FS be remounted?
+ * @filename: Name of file to which the o/p should be written
+ * @bw_report: Bandwidth report type (reads vs writes)
+ * @setup: Call back function to setup test environment
+ */
+struct resctrl_val_param {
+ char *resctrl_val;
+ char ctrlgrp[64];
+ char mongrp[64];
+ int cpu_no;
+ int span;
+ int mum_resctrlfs;
+ char filename[64];
+ char *bw_report;
+ char *bm_type;
+ int (*setup)(int num, ...);
+};
+
pid_t bm_pid, ppid;
int ben_count;
int remount_resctrlfs(bool mum_resctrlfs);
+int umount_resctrlfs(void);
char get_sock_num(int cpu_no);
int validate_bw_report_request(char *bw_report);
int validate_resctrl_feature_request(char *resctrl_val);
@@ -49,5 +75,6 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char
*mongrp,
int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
int group_fd, unsigned long flags);
int run_fill_buf(int span, int malloc_and_init_memory, int memflush, int op);
+int membw_val(char **benchmark_cmd, struct resctrl_val_param *param);
#endif /* RESCTRL_H */
--
2.5.0
