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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Memory bandwidth monitoring and allocation library
  *
  * Copyright (C) 2018 Intel Corporation
  *
  * Authors:
  *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
  *    Fenghua Yu <fenghua.yu@intel.com>
  */
 #include "resctrl.h"
 
 #define UNCORE_IMC      "uncore_imc"
 #define READ_FILE_NAME      "events/cas_count_read"
 #define WRITE_FILE_NAME     "events/cas_count_write"
 #define DYN_PMU_PATH        "/sys/bus/event_source/devices"
 #define SCALE           0.00006103515625
 #define MAX_IMCS        20
 #define MAX_TOKENS      5
 #define READ            0
 #define WRITE           1
 #define CON_MON_MBM_LOCAL_BYTES_PATH                \
     "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
 
 #define CON_MBM_LOCAL_BYTES_PATH        \
     "%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
 
 #define MON_MBM_LOCAL_BYTES_PATH        \
     "%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
 
 #define MBM_LOCAL_BYTES_PATH            \
     "%s/mon_data/mon_L3_%02d/mbm_local_bytes"
 
 #define CON_MON_LCC_OCCUP_PATH      \
     "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
 
 #define CON_LCC_OCCUP_PATH      \
     "%s/%s/mon_data/mon_L3_%02d/llc_occupancy"
 
 #define MON_LCC_OCCUP_PATH      \
     "%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
 
 #define LCC_OCCUP_PATH          \
     "%s/mon_data/mon_L3_%02d/llc_occupancy"
 
 struct membw_read_format {
     __u64 value;         /* The value of the event */
     __u64 time_enabled;  /* if PERF_FORMAT_TOTAL_TIME_ENABLED */
     __u64 time_running;  /* if PERF_FORMAT_TOTAL_TIME_RUNNING */
     __u64 id;            /* if PERF_FORMAT_ID */
 };
 
 struct imc_counter_config {
     __u32 type;
     __u64 event;
     __u64 umask;
     struct perf_event_attr pe;
     struct membw_read_format return_value;
     int fd;
 };
 
 static char mbm_total_path[1024];
 static int imcs;
 static struct imc_counter_config imc_counters_config[MAX_IMCS][2];
 
 void membw_initialize_perf_event_attr(int i, int j)
 {
     memset(&imc_counters_config[i][j].pe, 0,
            sizeof(struct perf_event_attr));
     imc_counters_config[i][j].pe.type = imc_counters_config[i][j].type;
     imc_counters_config[i][j].pe.size = sizeof(struct perf_event_attr);
     imc_counters_config[i][j].pe.disabled = 1;
     imc_counters_config[i][j].pe.inherit = 1;
     imc_counters_config[i][j].pe.exclude_guest = 0;
     imc_counters_config[i][j].pe.config =
         imc_counters_config[i][j].umask << 8 |
         imc_counters_config[i][j].event;
     imc_counters_config[i][j].pe.sample_type = PERF_SAMPLE_IDENTIFIER;
     imc_counters_config[i][j].pe.read_format =
         PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING;
 }
 
 void membw_ioctl_perf_event_ioc_reset_enable(int i, int j)
 {
     ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_RESET, 0);
     ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_ENABLE, 0);
 }
 
 void membw_ioctl_perf_event_ioc_disable(int i, int j)
 {
     ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_DISABLE, 0);
 }
 
 /*
  * get_event_and_umask: Parse config into event and umask
  * @cas_count_cfg:  Config
  * @count:      iMC number
  * @op:         Operation (read/write)
  */
 void get_event_and_umask(char *cas_count_cfg, int count, bool op)
 {
     char *token[MAX_TOKENS];
     int i = 0;
 
     strcat(cas_count_cfg, ",");
     token[0] = strtok(cas_count_cfg, "=,");
 
     for (i = 1; i < MAX_TOKENS; i++)
         token[i] = strtok(NULL, "=,");
 
     for (i = 0; i < MAX_TOKENS; i++) {
         if (!token[i])
             break;
         if (strcmp(token[i], "event") == 0) {
             if (op == READ)
                 imc_counters_config[count][READ].event =
                 strtol(token[i + 1], NULL, 16);
             else
                 imc_counters_config[count][WRITE].event =
                 strtol(token[i + 1], NULL, 16);
         }
         if (strcmp(token[i], "umask") == 0) {
             if (op == READ)
                 imc_counters_config[count][READ].umask =
                 strtol(token[i + 1], NULL, 16);
             else
                 imc_counters_config[count][WRITE].umask =
                 strtol(token[i + 1], NULL, 16);
         }
     }
 }
 
 static int open_perf_event(int i, int cpu_no, int j)
 {
     imc_counters_config[i][j].fd =
         perf_event_open(&imc_counters_config[i][j].pe, -1, cpu_no, -1,
                 PERF_FLAG_FD_CLOEXEC);
 
     if (imc_counters_config[i][j].fd == -1) {
         fprintf(stderr, "Error opening leader %llx\n",
             imc_counters_config[i][j].pe.config);
 
         return -1;
     }
 
     return 0;
 }
 
 /* Get type and config (read and write) of an iMC counter */
 static int read_from_imc_dir(char *imc_dir, int count)
 {
     char cas_count_cfg[1024], imc_counter_cfg[1024], imc_counter_type[1024];
     FILE *fp;
 
     /* Get type of iMC counter */
     sprintf(imc_counter_type, "%s%s", imc_dir, "type");
     fp = fopen(imc_counter_type, "r");
     if (!fp) {
         perror("Failed to open imc counter type file");
 
         return -1;
     }
     if (fscanf(fp, "%u", &imc_counters_config[count][READ].type) <= 0) {
         perror("Could not get imc type");
         fclose(fp);
 
         return -1;
     }
     fclose(fp);
 
     imc_counters_config[count][WRITE].type =
                 imc_counters_config[count][READ].type;
 
     /* Get read config */
     sprintf(imc_counter_cfg, "%s%s", imc_dir, READ_FILE_NAME);
     fp = fopen(imc_counter_cfg, "r");
     if (!fp) {
         perror("Failed to open imc config file");
 
         return -1;
     }
     if (fscanf(fp, "%s", cas_count_cfg) <= 0) {
         perror("Could not get imc cas count read");
         fclose(fp);
 
         return -1;
     }
     fclose(fp);
 
     get_event_and_umask(cas_count_cfg, count, READ);
 
     /* Get write config */
     sprintf(imc_counter_cfg, "%s%s", imc_dir, WRITE_FILE_NAME);
     fp = fopen(imc_counter_cfg, "r");
     if (!fp) {
         perror("Failed to open imc config file");
 
         return -1;
     }
     if  (fscanf(fp, "%s", cas_count_cfg) <= 0) {
         perror("Could not get imc cas count write");
         fclose(fp);
 
         return -1;
     }
     fclose(fp);
 
     get_event_and_umask(cas_count_cfg, count, WRITE);
 
     return 0;
 }
 
 /*
  * A system can have 'n' number of iMC (Integrated Memory Controller)
  * counters, get that 'n'. For each iMC counter get it's type and config.
  * Also, each counter has two configs, one for read and the other for write.
  * A config again has two parts, event and umask.
  * Enumerate all these details into an array of structures.
  *
  * Return: >= 0 on success. < 0 on failure.
  */
 static int num_of_imcs(void)
 {
     char imc_dir[512], *temp;
     unsigned int count = 0;
     struct dirent *ep;
     int ret;
     DIR *dp;
 
     dp = opendir(DYN_PMU_PATH);
     if (dp) {
         while ((ep = readdir(dp))) {
             temp = strstr(ep->d_name, UNCORE_IMC);
             if (!temp)
                 continue;
 
             /*
              * imc counters are named as "uncore_imc_<n>", hence
              * increment the pointer to point to <n>. Note that
              * sizeof(UNCORE_IMC) would count for null character as
              * well and hence the last underscore character in
              * uncore_imc'_' need not be counted.
              */
             temp = temp + sizeof(UNCORE_IMC);
 
             /*
              * Some directories under "DYN_PMU_PATH" could have
              * names like "uncore_imc_free_running", hence, check if
              * first character is a numerical digit or not.
              */
             if (temp[0] >= '0' && temp[0] <= '9') {
                 sprintf(imc_dir, "%s/%s/", DYN_PMU_PATH,
                     ep->d_name);
                 ret = read_from_imc_dir(imc_dir, count);
                 if (ret) {
                     closedir(dp);
 
                     return ret;
                 }
                 count++;
             }
         }
         closedir(dp);
         if (count == 0) {
             perror("Unable find iMC counters!\n");
 
             return -1;
         }
     } else {
         perror("Unable to open PMU directory!\n");
 
         return -1;
     }
 
     return count;
 }
 
 static int initialize_mem_bw_imc(void)
 {
     int imc, j;
 
     imcs = num_of_imcs();
     if (imcs <= 0)
         return imcs;
 
     /* Initialize perf_event_attr structures for all iMC's */
     for (imc = 0; imc < imcs; imc++) {
         for (j = 0; j < 2; j++)
             membw_initialize_perf_event_attr(imc, j);
     }
 
     return 0;
 }
 
 /*
  * get_mem_bw_imc:  Memory band width as reported by iMC counters
  * @cpu_no:     CPU number that the benchmark PID is binded to
  * @bw_report:      Bandwidth report type (reads, writes)
  *
  * Memory B/W utilized by a process on a socket can be calculated using
  * iMC counters. Perf events are used to read these counters.
  *
  * Return: = 0 on success. < 0 on failure.
  */
 static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
 {
     float reads, writes, of_mul_read, of_mul_write;
     int imc, j, ret;
 
     /* Start all iMC counters to log values (both read and write) */
     reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
     for (imc = 0; imc < imcs; imc++) {
         for (j = 0; j < 2; j++) {
             ret = open_perf_event(imc, cpu_no, j);
             if (ret)
                 return -1;
         }
         for (j = 0; j < 2; j++)
             membw_ioctl_perf_event_ioc_reset_enable(imc, j);
     }
 
     sleep(1);
 
     /* Stop counters after a second to get results (both read and write) */
     for (imc = 0; imc < imcs; imc++) {
         for (j = 0; j < 2; j++)
             membw_ioctl_perf_event_ioc_disable(imc, j);
     }
 
     /*
      * Get results which are stored in struct type imc_counter_config
      * Take over flow into consideration before calculating total b/w
      */
     for (imc = 0; imc < imcs; imc++) {
         struct imc_counter_config *r =
             &imc_counters_config[imc][READ];
         struct imc_counter_config *w =
             &imc_counters_config[imc][WRITE];
 
         if (read(r->fd, &r->return_value,
              sizeof(struct membw_read_format)) == -1) {
             perror("Couldn't get read b/w through iMC");
 
             return -1;
         }
 
         if (read(w->fd, &w->return_value,
              sizeof(struct membw_read_format)) == -1) {
             perror("Couldn't get write bw through iMC");
 
             return -1;
         }
 
         __u64 r_time_enabled = r->return_value.time_enabled;
         __u64 r_time_running = r->return_value.time_running;
 
         if (r_time_enabled != r_time_running)
             of_mul_read = (float)r_time_enabled /
                     (float)r_time_running;
 
         __u64 w_time_enabled = w->return_value.time_enabled;
         __u64 w_time_running = w->return_value.time_running;
 
         if (w_time_enabled != w_time_running)
             of_mul_write = (float)w_time_enabled /
                     (float)w_time_running;
         reads += r->return_value.value * of_mul_read * SCALE;
         writes += w->return_value.value * of_mul_write * SCALE;
     }
 
     for (imc = 0; imc < imcs; imc++) {
         close(imc_counters_config[imc][READ].fd);
         close(imc_counters_config[imc][WRITE].fd);
     }
 
     if (strcmp(bw_report, "reads") == 0) {
         *bw_imc = reads;
         return 0;
     }
 
     if (strcmp(bw_report, "writes") == 0) {
         *bw_imc = writes;
         return 0;
     }
 
     *bw_imc = reads + writes;
     return 0;
 }
 
 void set_mbm_path(const char *ctrlgrp, const char *mongrp, int resource_id)
 {
     if (ctrlgrp && mongrp)
         sprintf(mbm_total_path, CON_MON_MBM_LOCAL_BYTES_PATH,
             RESCTRL_PATH, ctrlgrp, mongrp, resource_id);
     else if (!ctrlgrp && mongrp)
         sprintf(mbm_total_path, MON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
             mongrp, resource_id);
     else if (ctrlgrp && !mongrp)
         sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
             ctrlgrp, resource_id);
     else if (!ctrlgrp && !mongrp)
         sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
             resource_id);
 }
 
 /*
  * initialize_mem_bw_resctrl:   Appropriately populate "mbm_total_path"
  * @ctrlgrp:            Name of the control monitor group (con_mon grp)
  * @mongrp:         Name of the monitor group (mon grp)
  * @cpu_no:         CPU number that the benchmark PID is binded to
  * @resctrl_val:        Resctrl feature (Eg: mbm, mba.. etc)
  */
 static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
                       int cpu_no, char *resctrl_val)
 {
     int resource_id;
 
     if (get_resource_id(cpu_no, &resource_id) < 0) {
         perror("Could not get resource_id");
         return;
     }
 
     if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
         set_mbm_path(ctrlgrp, mongrp, resource_id);
 
     if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
         if (ctrlgrp)
             sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH,
                 RESCTRL_PATH, ctrlgrp, resource_id);
         else
             sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH,
                 RESCTRL_PATH, resource_id);
     }
 }
 
 /*
  * Get MBM Local bytes as reported by resctrl FS
  * For MBM,
  * 1. If con_mon grp and mon grp are given, then read from con_mon grp's mon grp
  * 2. If only con_mon grp is given, then read from con_mon grp
  * 3. If both are not given, then read from root con_mon grp
  * For MBA,
  * 1. If con_mon grp is given, then read from it
  * 2. If con_mon grp is not given, then read from root con_mon grp
  */
 static int get_mem_bw_resctrl(unsigned long *mbm_total)
 {
     FILE *fp;
 
     fp = fopen(mbm_total_path, "r");
     if (!fp) {
         perror("Failed to open total bw file");
 
         return -1;
     }
     if (fscanf(fp, "%lu", mbm_total) <= 0) {
         perror("Could not get mbm local bytes");
         fclose(fp);
 
         return -1;
     }
     fclose(fp);
 
     return 0;
 }
 
 pid_t bm_pid, ppid;
 
 void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
 {
     kill(bm_pid, SIGKILL);
     umount_resctrlfs();
     tests_cleanup();
     ksft_print_msg("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)
 {
     unsigned long diff = fabs(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: %lu\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 Mem_BW_resc: %lu \t Difference: %lu\n",
                 bm_pid, bw_imc, bw_resc, diff) <= 0) {
             fclose(fp);
             perror("Could not log results.");
 
             return errno;
         }
         fclose(fp);
     }
 
     return 0;
 }
 
 static void set_cmt_path(const char *ctrlgrp, const char *mongrp, char sock_num)
 {
     if (strlen(ctrlgrp) && strlen(mongrp))
         sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
             ctrlgrp, mongrp, sock_num);
     else if (!strlen(ctrlgrp) && strlen(mongrp))
         sprintf(llc_occup_path, MON_LCC_OCCUP_PATH, RESCTRL_PATH,
             mongrp, sock_num);
     else if (strlen(ctrlgrp) && !strlen(mongrp))
         sprintf(llc_occup_path, CON_LCC_OCCUP_PATH, RESCTRL_PATH,
             ctrlgrp, sock_num);
     else if (!strlen(ctrlgrp) && !strlen(mongrp))
         sprintf(llc_occup_path, LCC_OCCUP_PATH, RESCTRL_PATH, sock_num);
 }
 
 /*
  * initialize_llc_occu_resctrl: Appropriately populate "llc_occup_path"
  * @ctrlgrp:            Name of the control monitor group (con_mon grp)
  * @mongrp:         Name of the monitor group (mon grp)
  * @cpu_no:         CPU number that the benchmark PID is binded to
  * @resctrl_val:        Resctrl feature (Eg: cat, cmt.. etc)
  */
 static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
                     int cpu_no, char *resctrl_val)
 {
     int resource_id;
 
     if (get_resource_id(cpu_no, &resource_id) < 0) {
         perror("# Unable to resource_id");
         return;
     }
 
     if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
         set_cmt_path(ctrlgrp, mongrp, resource_id);
 }
 
 static int
 measure_vals(struct resctrl_val_param *param, unsigned long *bw_resc_start)
 {
     unsigned long bw_resc, bw_resc_end;
     float bw_imc;
     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.
      */
     ret = get_mem_bw_imc(param->cpu_no, param->bw_report, &bw_imc);
     if (ret < 0)
         return ret;
 
     ret = get_mem_bw_resctrl(&bw_resc_end);
     if (ret < 0)
         return ret;
 
     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;
 }
 
 /*
  * resctrl_val: execute benchmark and measure memory bandwidth on
  *          the benchmark
  * @benchmark_cmd:  benchmark command and its arguments
  * @param:      parameters passed to resctrl_val()
  *
  * Return:      0 on success. non-zero on failure.
  */
 int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param)
 {
     char *resctrl_val = param->resctrl_val;
     unsigned long bw_resc_start = 0;
     struct sigaction sigact;
     int ret = 0, pipefd[2];
     char pipe_message = 0;
     union sigval value;
 
     if (strcmp(param->filename, "") == 0)
         sprintf(param->filename, "stdio");
 
     if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
         !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
         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();
 
     if (pipe(pipefd)) {
         perror("# Unable to create pipe");
 
         return -1;
     }
 
     /*
      * 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 -1;
     }
 
     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");
 
         /* Tell parent that child is ready */
         close(pipefd[0]);
         pipe_message = 1;
         if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
             sizeof(pipe_message)) {
             perror("# failed signaling parent process");
             close(pipefd[1]);
             return -1;
         }
         close(pipefd[1]);
 
         /* Suspend child until delivery of "SIGUSR1" from parent */
         sigsuspend(&sigact.sa_mask);
 
         PARENT_EXIT("Child is done");
     }
 
     ksft_print_msg("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(SIGTERM, &sigact, NULL) ||
         sigaction(SIGHUP, &sigact, NULL)) {
         perror("# sigaction");
         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 control&monitoring grp in resctrl FS */
     ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
                       resctrl_val);
     if (ret)
         goto out;
 
     if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
         !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
         ret = initialize_mem_bw_imc();
         if (ret)
             goto out;
 
         initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
                       param->cpu_no, resctrl_val);
     } else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
         initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
                         param->cpu_no, resctrl_val);
 
     /* Parent waits for child to be ready. */
     close(pipefd[1]);
     while (pipe_message != 1) {
         if (read(pipefd[0], &pipe_message, sizeof(pipe_message)) <
             sizeof(pipe_message)) {
             perror("# failed reading message from child process");
             close(pipefd[0]);
             goto out;
         }
     }
     close(pipefd[0]);
 
     /* Signal child to start benchmark */
     if (sigqueue(bm_pid, SIGUSR1, value) == -1) {
         perror("# sigqueue SIGUSR1 to child");
         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 (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
             !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
             ret = param->setup(1, param);
             if (ret) {
                 ret = 0;
                 break;
             }
 
             ret = measure_vals(param, &bw_resc_start);
             if (ret)
                 break;
         } else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
             ret = param->setup(1, param);
             if (ret) {
                 ret = 0;
                 break;
             }
             sleep(1);
             ret = measure_cache_vals(param, bm_pid);
             if (ret)
                 break;
         } else {
             break;
         }
     }
 
 out:
     kill(bm_pid, SIGKILL);
     umount_resctrlfs();
 
     return ret;
 }

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