// SPDX-License-Identifier: GPL-2.0-only /* * POWER Data Stream Control Register (DSCR) sysfs thread test * * This test updates the system wide DSCR default value through * sysfs interface which should then update all the CPU specific * DSCR default values which must also be then visible to threads * executing on individual CPUs on the system. * * Copyright 2015, Anshuman Khandual, IBM Corporation. */ #define _GNU_SOURCE #include "dscr.h" static int test_thread_dscr(unsigned long val) { unsigned long cur_dscr, cur_dscr_usr; cur_dscr = get_dscr(); cur_dscr_usr = get_dscr_usr(); if (val != cur_dscr) { printf("[cpu %d] Kernel DSCR should be %ld but is %ld\n", sched_getcpu(), val, cur_dscr); return 1; } if (val != cur_dscr_usr) { printf("[cpu %d] User DSCR should be %ld but is %ld\n", sched_getcpu(), val, cur_dscr_usr); return 1; } return 0; } static int check_cpu_dscr_thread(unsigned long val) { cpu_set_t mask; int cpu; for (cpu = 0; cpu < CPU_SETSIZE; cpu++) { CPU_ZERO(&mask); CPU_SET(cpu, &mask); if (sched_setaffinity(0, sizeof(mask), &mask)) continue; if (test_thread_dscr(val)) return 1; } return 0; } int dscr_sysfs_thread(void) { unsigned long orig_dscr_default; int i, j; SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR)); orig_dscr_default = get_default_dscr(); for (i = 0; i < COUNT; i++) { for (j = 0; j < DSCR_MAX; j++) { set_default_dscr(j); if (check_cpu_dscr_thread(j)) goto fail; } } set_default_dscr(orig_dscr_default); return 0; fail: set_default_dscr(orig_dscr_default); return 1; } int main(int argc, char *argv[]) { return test_harness(dscr_sysfs_thread, "dscr_sysfs_thread_test"); }