base/arch/x86_64/calibration/calibrate.c

Go to the documentation of this file.

/*
 * Copyright (C) 2003 Paolo Mantegazza <mantegazza@aero.polimi.it>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.

 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */

#include <float.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <signal.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/io.h>
#include <getopt.h>
#include <pthread.h>
#include <math.h>

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <termio.h>
#include <sys/poll.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <unistd.h>
#include <ctype.h>
#include <time.h>
#include <signal.h>

#include <asm/rtai_srq.h>
#include <rtai_fifos.h>
#include "calibrate.h"

struct option options[] = {
    { "help",       0, 0, 'h' },
    { "r8254",      0, 0, 'r' },
    { "kernel",     0, 0, 'k' },
    { "user",       0, 0, 'u' },
    { "period",     1, 0, 'p' },
    { "time",       1, 0, 't' },
    { "cpu",        0, 0, 'c' },
    { "apic",       0, 0, 'a' },
    { "both",       0, 0, 'b' },
    { "scope",      1, 0, 's' },
    { "interrupt",  0, 0, 'i' },
    { NULL,         0, 0,  0 }
};

void print_usage(void)
{
    fputs(
    ("\n*** i386 calibrations ***\n"
     "\n"
     "OPTIONS:\n"
     "  -h, --help\n"
     "      print usage\n"
     "  -r, --r8254\n"
     "      calibrate 8254 oneshot programming type\n"
     "  -k, --kernel\n"
     "      oneshot latency calibrated for scheduling kernel space tasks\n"
     "  -u, --user\n"
     "      oneshot latency calibrated for scheduling user space tasks\n"
     "  -p <period (us)>, --period <period (us)>\n"
     "      the period of the underlying hard real time task/intr, default 100 (us)\n"
     "  -t <duration (s)>, --time <duration (s)>\n"
     "      set the duration of the requested calibration, default 5 (s)\n"
     "  -c, --cpufreq\n"
     "      calibrate cpu frequency\n"
     "  -a, --apic\n"
     "      calibrate apic frequency\n"
     "  -b, --both\n"
     "      calibrate both apic and cpu frequency\n"
     "  -i, --interrupt\n"
     "      check worst case interrupt locking/contention on your PC\n"
     "  -s<y/n>, --scope<y/n>\n"
     "      toggle parport bit to monitor scheduling on a scope, default y(es)\n"
     "\n")
    , stderr);
}

static void endme(int dummy) { }

static void unload_kernel_helper (void)

{
    int rv;
    char modunload[1024];

    snprintf(modunload,sizeof(modunload),"/sbin/rmmod %s >/dev/null 2>&1",KERNEL_HELPER_PATH);
    rv = system(modunload);
}

int main(int argc, char *argv[])
{
    int srq, fifo, command, commands[20], ncommands, c, option_index, i, rv;
    struct params_t params;
    char str[80], nm[RTF_NAMELEN+1], modload[1024];
    unsigned long period = 100, duration = 5, parport = 'y';
    unsigned long args[MAXARGS];
    struct pollfd polls[2] = { { 0, POLLIN }, { 0, POLLIN } };

    option_index = ncommands = 0;
    while (1) {
        if ((c = getopt_long(argc, argv, "hrkucabip:t:s:", options, &option_index)) == -1) {
            break;
        }
        switch(c) {
            case 'h': {
                print_usage();
                exit(0);
            }
            case 'r':
            case 'u':
            case 'c':
            case 'b':
            case 'a':
            case 'i':
            case 'k': {
                commands[ncommands++] = c;
                break;
            }
            case 'p': {
                period = atoi(optarg);
                break;
            }
            case 't': {
                duration = atoi(optarg);
                break;
            }
            case 's': {
                parport = optarg[0] == 'y' ? 'y' : 'n';
                break;
            }
        }
    }
    if (ncommands <= 0) {
        printf("\n*** NOTHING TO BE DONE ***\n");
        exit(0);
    }

    atexit(&unload_kernel_helper);

    snprintf(modload,sizeof(modload),"/sbin/insmod %s >/dev/null 2>&1",KERNEL_HELPER_PATH);
    rv = system(modload);

    signal(SIGINT, endme);

    srq = rtai_open_srq(CALSRQ);
    if ((fifo = open(rtf_getfifobyminor(0,nm,sizeof(nm)), O_RDONLY)) < 0) {
        printf("Error opening %s\n",nm);
        exit(1);
    }
    polls[1].fd = fifo;

    args[0] = GET_PARAMS;
    rtai_srq(srq, (unsigned long)args);
    rv = read(fifo, &params, sizeof(params));
    printf("\n*** NUMBER OF REQUESTS: %d. ***\n", ncommands);

    for (i = 0; i < ncommands; i++) {
        switch (command = commands[i]) {

            case 'r': {
                args[0] = CAL_8254;
                printf("\n*** '#define SETUP_TIME_8254 %lu', IN USE %lu ***\n\n", (unsigned long) rtai_srq(srq, (unsigned long)args), params.setup_time_8254);
                break;
            }

            case 'k': {
                int average;
                args[0] = KLATENCY;
                args[1] = period;
                args[2] = duration;
                printf("\n*** KERNEL SPACE LATENCY CALIBRATION, wait %lu seconds for it ... ***\n", args[2]);
                args[2] = (1000000*args[2])/args[1];
                args[1] *= 1000;
                rtai_srq(srq, (unsigned long)args);
                rv = read(fifo, &average, sizeof(average));
                average /= (int)args[2];
                    if (params.mp) {
                        printf("\n*** '#define LATENCY_APIC %d' (IN USE %lu)\n\n", (int)params.latency_apic + average, params.latency_apic);
                } else {
                    printf("\n*** '#define LATENCY_8254 %d' (IN USE %lu)\n\n", (int)params.latency_8254 + average, params.latency_8254);
                }
                args[0] = END_KLATENCY;
                rtai_srq(srq, (unsigned long)args);
                break;
            }

            case 'u': {
                int pid, average;
                args[1] = period;
                args[2] = duration;
                printf("\n*** USER SPACE LATENCY CALIBRATION, wait %lu seconds for it ... ***\n", args[2]);
                args[2] = (1000000*args[2])/args[1];
                args[1] *= 1000;
                sprintf(str, "%lu", args[1]);
                sprintf(str + sizeof(str)/2, "%lu", args[2]);
                pid = fork();
                if (!pid) {
                    execl(USER_HELPER_PATH, USER_HELPER_PATH, str, str + sizeof(str)/2, NULL);
                    _exit(1);
                }
                rv = read(fifo, &average, sizeof(average));
                waitpid(pid, 0, 0);
                if (kill(pid,0) < 0)
                    {
//                  printf("\n*** Cannot execute calibration helper %s -- aborting\n",USER_HELPER_PATH);
//                  exit(1);
                    }
                average /= (int)args[2];
                    if (params.mp) {
                        printf("\n*** '#define LATENCY_APIC %d' (IN USE %lu)\n\n", (int)params.latency_apic + average, params.latency_apic);
                } else {
                    printf("\n*** '#define LATENCY_8254 %d' (IN USE %lu)\n\n", (int)params.latency_8254 + average, params.latency_8254);
                }
                break;
            }

            case 'a': 
                if (!params.mp) {
                    printf("*** APIC FREQUENCY CALIBRATION NOT AVAILABLE UNDER UP ***\n");  
                    break;  
                }
            case 'b':
            case 'c': {
                unsigned long time, cpu_freq = 0, apic_freq = 0;
                struct times_t times;
                args[0] = FREQ_CAL;
                args[1] = duration;
                printf("\n->>> FREQ CALIB (PRINTING EVERY %lu SECONDS, press enter to end calibrating) <<<-\n\n", args[1]);
                rtai_srq(srq, (unsigned long)args);
                time = 0;
                while (1) {
                    time += args[1];
                    if (poll(polls, 2, 1000*duration) > 0 &&polls[0].revents) {
                        getchar();
                        args[0] = END_FREQ_CAL;
                        rtai_srq(srq, (unsigned long)args);
                        if (command == 'c' || command == 'b') {
                            printf("\n*** '#define CPU_FREQ %lu', IN USE %lu ***\n\n", cpu_freq, params.cpu_freq);
                        }
                        if (params.mp && (command == 'a' || command == 'b')) {
                            printf("\n*** '#define APIC_FREQ %lu', IN USE %lu ***\n\n", apic_freq, params.freq_apic);
                        }
                        break;
                    }
                    rv = read(fifo, &times, sizeof(times));
                    if (command == 'c' || command == 'b') {
                        cpu_freq = (((double)times.cpu_time)*params.clock_tick_rate)/(((double)times.intrs)*params.latch) + 0.49999999999999999;
                        printf("\n->>> MEASURED CPU_FREQ: %lu (Hz) [%lu (s)], IN USE %lu (Hz) <<<-\n", cpu_freq, time, params.cpu_freq);
                    }
                    if (params.mp && (command == 'a' || command == 'b')) {
                        apic_freq = (((double)times.apic_time)*params.clock_tick_rate)/(((double)times.intrs)*params.latch) + 0.49999999999999999;
                        printf("\n->>> MEASURED APIC_FREQ: %lu (Hz) [%lu (s)], IN USE %lu (Hz) <<<-\n", apic_freq, time, params.freq_apic);
                    }
                }
                break;
            }

            case 'i': {
                time_t timestamp;
                struct tm *tm_timestamp;
                args[0] = BUS_CHECK;
                args[1] = period;
                args[2] = 1;
                args[3] = parport;
                printf("\n->>> INTERRUPT LATENCY CHECK (press enter to end check) <<<-\n\n");
                args[1] *= 1000;
                args[2] *= 1000;
                rtai_srq(srq, (unsigned long)args);
                while (1) {
                    int maxj;
                    if (poll(polls, 2, 100) > 0) {
                        if (polls[0].revents) {
                            getchar();
                            args[0] = END_BUS_CHECK;
                            rtai_srq(srq, (unsigned long)args);
                            break;
                        }
                        rv = read(fifo, &maxj, sizeof(maxj));
                        time(&timestamp);
                        tm_timestamp = localtime(&timestamp);
                        printf("%04d/%02d/%0d-%02d:%02d:%02d -> ", tm_timestamp->tm_year+1900, tm_timestamp->tm_mon+1, tm_timestamp->tm_mday, tm_timestamp->tm_hour, tm_timestamp->tm_min, tm_timestamp->tm_sec);
                        printf("%d.%-3d (us)\n", maxj/1000, maxj%1000);
                    }
                }
                break;
            }

        }
    }
    exit(0);
}

---