diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/tst-skeleton-affinity.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/tst-skeleton-affinity.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/tst-skeleton-affinity.c b/sysdeps/unix/sysv/linux/tst-skeleton-affinity.c new file mode 100644 index 0000000..8b8347d --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-skeleton-affinity.c @@ -0,0 +1,278 @@ +/* Generic test case for CPU affinity functions. + Copyright (C) 2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C 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 2.1 of the License, or (at your option) any later version. + + The GNU C 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 the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +/* This file is included by the tst-affinity*.c files to test the two + variants of the functions, under different conditions. The + following functions have to be definied: + + static int getaffinity (size_t, cpu_set_t *); + static int setaffinity (size_t, const cpu_set_t *); + static bool early_test (struct conf *); + + The first two functions shall affect the affinity mask for the + current thread and return 0 for success, -1 for error (with an + error code in errno). + + early_test is invoked before the tests in this file affect the + affinity masks. If it returns true, testing continues, otherwise + no more tests run and the overall test exits with status 1. +*/ + +#include <errno.h> +#include <limits.h> +#include <sched.h> +#include <stdbool.h> +#include <stdio.h> + +/* CPU set configuration determined. Can be used from early_test. */ +struct conf +{ + int set_size; /* in bits */ + int last_cpu; +}; + +static int +find_set_size (void) +{ + /* There is considerable controversy about how to determine the size + of the kernel CPU mask. The probing loop below is only intended + for testing purposes. */ + for (int num_cpus = 64; num_cpus <= INT_MAX / 2; ++num_cpus) + { + cpu_set_t *set = CPU_ALLOC (num_cpus); + size_t size = CPU_ALLOC_SIZE (num_cpus); + + if (set == NULL) + { + printf ("error: CPU_ALLOC (%d) failed\n", num_cpus); + return -1; + } + if (getaffinity (size, set) == 0) + { + CPU_FREE (set); + return num_cpus; + } + if (errno != EINVAL) + { + printf ("error: getaffinity for %d CPUs: %m\n", num_cpus); + CPU_FREE (set); + return -1; + } + CPU_FREE (set); + } + puts ("error: Cannot find maximum CPU number"); + return -1; +} + +static int +find_last_cpu (const cpu_set_t *set, size_t size) +{ + /* We need to determine the set size with CPU_COUNT_S and the + cpus_found counter because there is no direct way to obtain the + actual CPU set size, in bits, from the value of + CPU_ALLOC_SIZE. */ + size_t cpus_found = 0; + size_t total_cpus = CPU_COUNT_S (size, set); + int last_cpu = -1; + + for (int cpu = 0; cpus_found < total_cpus; ++cpu) + { + if (CPU_ISSET_S (cpu, size, set)) + { + last_cpu = cpu; + ++cpus_found; + } + } + return last_cpu; +} + +static void +setup_conf (struct conf *conf) +{ + *conf = (struct conf) {-1, -1}; + conf->set_size = find_set_size (); + if (conf->set_size > 0) + { + cpu_set_t *set = CPU_ALLOC (conf->set_size); + + if (set == NULL) + { + printf ("error: CPU_ALLOC (%d) failed\n", conf->set_size); + CPU_FREE (set); + return; + } + if (getaffinity (CPU_ALLOC_SIZE (conf->set_size), set) < 0) + { + printf ("error: getaffinity failed: %m\n"); + CPU_FREE (set); + return; + } + conf->last_cpu = find_last_cpu (set, CPU_ALLOC_SIZE (conf->set_size)); + if (conf->last_cpu < 0) + puts ("info: No test CPU found"); + CPU_FREE (set); + } +} + +static bool +test_size (const struct conf *conf, size_t size) +{ + if (size < conf->set_size) + { + printf ("info: Test not run for CPU set size %zu\n", size); + return true; + } + + cpu_set_t *initial_set = CPU_ALLOC (size); + cpu_set_t *set2 = CPU_ALLOC (size); + cpu_set_t *active_cpu_set = CPU_ALLOC (size); + + if (initial_set == NULL || set2 == NULL || active_cpu_set == NULL) + { + printf ("error: size %zu: CPU_ALLOC failed\n", size); + return false; + } + size_t kernel_size = CPU_ALLOC_SIZE (size); + + if (getaffinity (kernel_size, initial_set) < 0) + { + printf ("error: size %zu: getaffinity: %m\n", size); + return false; + } + if (setaffinity (kernel_size, initial_set) < 0) + { + printf ("error: size %zu: setaffinity: %m\n", size); + return true; + } + + /* Use one-CPU set to test switching between CPUs. */ + int last_active_cpu = -1; + for (int cpu = 0; cpu <= conf->last_cpu; ++cpu) + { + int active_cpu = sched_getcpu (); + if (last_active_cpu >= 0 && last_active_cpu != active_cpu) + { + printf ("error: Unexpected CPU %d, expected %d\n", + active_cpu, last_active_cpu); + return false; + } + + if (!CPU_ISSET_S (cpu, kernel_size, initial_set)) + continue; + last_active_cpu = cpu; + + CPU_ZERO_S (kernel_size, active_cpu_set); + CPU_SET_S (cpu, kernel_size, active_cpu_set); + if (setaffinity (kernel_size, active_cpu_set) < 0) + { + printf ("error: size %zu: setaffinity (%d): %m\n", size, cpu); + return false; + } + active_cpu = sched_getcpu (); + if (active_cpu != cpu) + { + printf ("error: Unexpected CPU %d, expected %d\n", active_cpu, cpu); + return false; + } + if (getaffinity (kernel_size, set2) < 0) + { + printf ("error: size %zu: getaffinity (2): %m\n", size); + return false; + } + if (!CPU_EQUAL_S (kernel_size, active_cpu_set, set2)) + { + printf ("error: size %zu: CPU sets do not match\n", size); + return false; + } + } + + /* Test setting the all-ones set. */ + for (int cpu = 0; cpu < size; ++cpu) + CPU_SET_S (cpu, kernel_size, set2); + if (setaffinity (kernel_size, set2) < 0) + { + printf ("error: size %zu: setaffinity (3): %m\n", size); + return false; + } + + if (setaffinity (kernel_size, initial_set) < 0) + { + printf ("error: size %zu: setaffinity (4): %m\n", size); + return false; + } + if (getaffinity (kernel_size, set2) < 0) + { + printf ("error: size %zu: getaffinity (3): %m\n", size); + return false; + } + if (!CPU_EQUAL_S (kernel_size, initial_set, set2)) + { + printf ("error: size %zu: CPU sets do not match (2)\n", size); + return false; + } + + CPU_FREE (initial_set); + CPU_FREE (set2); + CPU_FREE (active_cpu_set); + + return true; +} + +static int +do_test (void) +{ + { + cpu_set_t set; + if (getaffinity (sizeof (set), &set) < 0 && errno == ENOSYS) + { + puts ("warning: getaffinity not supported, test cannot run"); + return 0; + } + if (sched_getcpu () < 0 && errno == ENOSYS) + { + puts ("warning: sched_getcpu not supported, test cannot run"); + return 0; + } + } + + struct conf conf; + setup_conf (&conf); + printf ("info: Detected CPU set size (in bits): %d\n", conf.set_size); + printf ("info: Maximum test CPU: %d\n", conf.last_cpu); + if (conf.set_size < 0 || conf.last_cpu < 0) + return 1; + + if (!early_test (&conf)) + return 1; + + bool error = false; + error |= !test_size (&conf, 1024); + error |= !test_size (&conf, conf.set_size); + error |= !test_size (&conf, 2); + error |= !test_size (&conf, 32); + error |= !test_size (&conf, 40); + error |= !test_size (&conf, 64); + error |= !test_size (&conf, 96); + error |= !test_size (&conf, 128); + error |= !test_size (&conf, 256); + error |= !test_size (&conf, 8192); + return error; +} + +#define TEST_FUNCTION do_test () +#include "../test-skeleton.c" |