tools/testing/selftests/powerpc/dscr/dscr_sysfs_thread_test.c

   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
  18 static 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
  39 static 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
  57 int 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;
  72 fail:
  73         set_default_dscr(orig_dscr_default);
  74         return 1;
  75 }
  76
  77 int main(int argc, char *argv[])
  78 {
  79         return test_harness(dscr_sysfs_thread, "dscr_sysfs_thread_test");
  80 }