LXR linux/tools/testing/selftests/powerpc/dscr/dscr_sysfs_thread

   1/*
   2 * POWER Data Stream Control Register (DSCR) sysfs thread test
   3 *
   4 * This test updates the system wide DSCR default value through
   5 * sysfs interface which should then update all the CPU specific
   6 * DSCR default values which must also be then visible to threads
   7 * executing on individual CPUs on the system.
   8 *
   9 * Copyright 2015, Anshuman Khandual, IBM Corporation.
  10 *
  11 * This program is free software; you can redistribute it and/or modify it
  12 * under the terms of the GNU General Public License version 2 as published
  13 * by the Free Software Foundation.
  14 */
  15#define _GNU_SOURCE
  16#include "dscr.h"
  17
  18static int test_thread_dscr(unsigned long val)
  19{
  20        unsigned long cur_dscr, cur_dscr_usr;
  21
  22        cur_dscr = get_dscr();
  23        cur_dscr_usr = get_dscr_usr();
  24
  25        if (val != cur_dscr) {
  26                printf("[cpu %d] Kernel DSCR should be %ld but is %ld\n",
  27                                        sched_getcpu(), val, cur_dscr);
  28                return 1;
  29        }
  30
  31        if (val != cur_dscr_usr) {
  32                printf("[cpu %d] User DSCR should be %ld but is %ld\n",
  33                                        sched_getcpu(), val, cur_dscr_usr);
  34                return 1;
  35        }
  36        return 0;
  37}
  38
  39static int check_cpu_dscr_thread(unsigned long val)
  40{
  41        cpu_set_t mask;
  42        int cpu;
  43
  44        for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
  45                CPU_ZERO(&mask);
  46                CPU_SET(cpu, &mask);
  47                if (sched_setaffinity(0, sizeof(mask), &mask))
  48                        continue;
  49
  50                if (test_thread_dscr(val))
  51                        return 1;
  52        }
  53        return 0;
  54
  55}
  56
  57int dscr_sysfs_thread(void)
  58{
  59        unsigned long orig_dscr_default;
  60        int i, j;
  61
  62        orig_dscr_default = get_default_dscr();
  63        for (i = 0; i < COUNT; i++) {
  64                for (j = 0; j < DSCR_MAX; j++) {
  65                        set_default_dscr(j);
  66                        if (check_cpu_dscr_thread(j))
  67                                goto fail;
  68                }
  69        }
  70        set_default_dscr(orig_dscr_default);
  71        return 0;
  72fail:
  73        set_default_dscr(orig_dscr_default);
  74        return 1;
  75}
  76
  77int main(int argc, char *argv[])
  78{
  79        return test_harness(dscr_sysfs_thread, "dscr_sysfs_thread_test");
  80}
  81