diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/tst-skeleton-thread-affinity.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/tst-skeleton-thread-affinity.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/tst-skeleton-thread-affinity.c b/sysdeps/unix/sysv/linux/tst-skeleton-thread-affinity.c new file mode 100644 index 0000000000..69e09bb5cd --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-skeleton-thread-affinity.c @@ -0,0 +1,280 @@ +/* Generic test for CPU affinity functions, multi-threaded variant. + 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/>. */ + +/* Before including this file, a test has to declare the helper + getaffinity and setaffinity functions described in + tst-skeleton-affinity.c, which is included below. */ + +#include <errno.h> +#include <pthread.h> +#include <stdbool.h> +#include <stdlib.h> +#include <sys/time.h> + +struct conf; +static bool early_test (struct conf *); + +/* Arbitrary run time for each pass. */ +#define PASS_TIMEOUT 2 + +/* There are two passes (one with sched_yield, one without), and we + double the timeout to be on the safe side. */ +#define TIMEOUT (2 * PASS_TIMEOUT * 2) + +#include "tst-skeleton-affinity.c" + +/* 0 if still running, 1 of stopping requested. */ +static int still_running; + +/* 0 if no scheduling failures, 1 if failures are encountered. */ +static int failed; + +static void * +thread_burn_one_cpu (void *closure) +{ + int cpu = (uintptr_t) closure; + while (__atomic_load_n (&still_running, __ATOMIC_RELAXED) == 0) + { + int current = sched_getcpu (); + if (sched_getcpu () != cpu) + { + printf ("error: Pinned thread %d ran on impossible cpu %d\n", + cpu, current); + __atomic_store_n (&failed, 1, __ATOMIC_RELAXED); + /* Terminate early. */ + __atomic_store_n (&still_running, 1, __ATOMIC_RELAXED); + } + } + return NULL; +} + +struct burn_thread +{ + pthread_t self; + struct conf *conf; + cpu_set_t *initial_set; + cpu_set_t *seen_set; + int thread; +}; + +static void * +thread_burn_any_cpu (void *closure) +{ + struct burn_thread *param = closure; + + /* Schedule this thread around a bit to see if it lands on another + CPU. Run this for 2 seconds, once with sched_yield, once + without. */ + for (int pass = 1; pass <= 2; ++pass) + { + time_t start = time (NULL); + while (time (NULL) - start <= PASS_TIMEOUT) + { + int cpu = sched_getcpu (); + if (cpu > param->conf->last_cpu + || !CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (param->conf->set_size), + param->initial_set)) + { + printf ("error: Unpinned thread %d ran on impossible CPU %d\n", + param->thread, cpu); + __atomic_store_n (&failed, 1, __ATOMIC_RELAXED); + return NULL; + } + CPU_SET_S (cpu, CPU_ALLOC_SIZE (param->conf->set_size), + param->seen_set); + if (pass == 1) + sched_yield (); + } + } + return NULL; +} + +static void +stop_and_join_threads (struct conf *conf, cpu_set_t *set, + pthread_t *pinned_first, pthread_t *pinned_last, + struct burn_thread *other_first, + struct burn_thread *other_last) +{ + __atomic_store_n (&still_running, 1, __ATOMIC_RELAXED); + for (pthread_t *p = pinned_first; p < pinned_last; ++p) + { + int cpu = p - pinned_first; + if (!CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), set)) + continue; + + int ret = pthread_join (*p, NULL); + if (ret != 0) + { + printf ("error: Failed to join thread %d: %s\n", cpu, strerror (ret)); + fflush (stdout); + /* Cannot shut down cleanly with threads still running. */ + abort (); + } + } + + for (struct burn_thread *p = other_first; p < other_last; ++p) + { + int cpu = p - other_first; + if (!CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), set)) + continue; + + int ret = pthread_join (p->self, NULL); + if (ret != 0) + { + printf ("error: Failed to join thread %d: %s\n", cpu, strerror (ret)); + fflush (stdout); + /* Cannot shut down cleanly with threads still running. */ + abort (); + } + } +} + +/* Tries to check that the initial set of CPUs is complete and that + the main thread will not run on any other threads. */ +static bool +early_test (struct conf *conf) +{ + pthread_t *pinned_threads + = calloc (conf->last_cpu + 1, sizeof (*pinned_threads)); + struct burn_thread *other_threads + = calloc (conf->last_cpu + 1, sizeof (*other_threads)); + cpu_set_t *initial_set = CPU_ALLOC (conf->set_size); + cpu_set_t *scratch_set = CPU_ALLOC (conf->set_size); + + if (pinned_threads == NULL || other_threads == NULL + || initial_set == NULL || scratch_set == NULL) + { + puts ("error: Memory allocation failure"); + return false; + } + if (getaffinity (CPU_ALLOC_SIZE (conf->set_size), initial_set) < 0) + { + printf ("error: pthread_getaffinity_np failed: %m\n"); + return false; + } + for (int cpu = 0; cpu <= conf->last_cpu; ++cpu) + { + if (!CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), initial_set)) + continue; + other_threads[cpu].conf = conf; + other_threads[cpu].initial_set = initial_set; + other_threads[cpu].thread = cpu; + other_threads[cpu].seen_set = CPU_ALLOC (conf->set_size); + if (other_threads[cpu].seen_set == NULL) + { + puts ("error: Memory allocation failure"); + return false; + } + CPU_ZERO_S (CPU_ALLOC_SIZE (conf->set_size), + other_threads[cpu].seen_set); + } + + pthread_attr_t attr; + int ret = pthread_attr_init (&attr); + if (ret != 0) + { + printf ("error: pthread_attr_init failed: %s\n", strerror (ret)); + return false; + } + + /* Spawn a thread pinned to each available CPU. */ + for (int cpu = 0; cpu <= conf->last_cpu; ++cpu) + { + if (!CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), initial_set)) + continue; + CPU_ZERO_S (CPU_ALLOC_SIZE (conf->set_size), scratch_set); + CPU_SET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), scratch_set); + ret = pthread_attr_setaffinity_np + (&attr, CPU_ALLOC_SIZE (conf->set_size), scratch_set); + if (ret != 0) + { + printf ("error: pthread_attr_setaffinity_np for CPU %d failed: %s\n", + cpu, strerror (ret)); + stop_and_join_threads (conf, initial_set, + pinned_threads, pinned_threads + cpu, + NULL, NULL); + return false; + } + ret = pthread_create (pinned_threads + cpu, &attr, + thread_burn_one_cpu, (void *) (uintptr_t) cpu); + if (ret != 0) + { + printf ("error: pthread_create for CPU %d failed: %s\n", + cpu, strerror (ret)); + stop_and_join_threads (conf, initial_set, + pinned_threads, pinned_threads + cpu, + NULL, NULL); + return false; + } + } + + /* Spawn another set of threads running on all CPUs. */ + for (int cpu = 0; cpu <= conf->last_cpu; ++cpu) + { + if (!CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), initial_set)) + continue; + ret = pthread_create (&other_threads[cpu].self, NULL, + thread_burn_any_cpu, other_threads + cpu); + if (ret != 0) + { + printf ("error: pthread_create for thread %d failed: %s\n", + cpu, strerror (ret)); + stop_and_join_threads (conf, initial_set, + pinned_threads, + pinned_threads + conf->last_cpu + 1, + other_threads, other_threads + cpu); + return false; + } + } + + /* Main thread. */ + struct burn_thread main_thread; + main_thread.conf = conf; + main_thread.initial_set = initial_set; + main_thread.seen_set = scratch_set; + main_thread.thread = -1; + CPU_ZERO_S (CPU_ALLOC_SIZE (conf->set_size), main_thread.seen_set); + thread_burn_any_cpu (&main_thread); + stop_and_join_threads (conf, initial_set, + pinned_threads, + pinned_threads + conf->last_cpu + 1, + other_threads, other_threads + conf->last_cpu + 1); + + printf ("info: Main thread ran on %d CPU(s) of %d available CPU(s)\n", + CPU_COUNT_S (CPU_ALLOC_SIZE (conf->set_size), scratch_set), + CPU_COUNT_S (CPU_ALLOC_SIZE (conf->set_size), initial_set)); + CPU_ZERO_S (CPU_ALLOC_SIZE (conf->set_size), scratch_set); + for (int cpu = 0; cpu <= conf->last_cpu; ++cpu) + { + if (!CPU_ISSET_S (cpu, CPU_ALLOC_SIZE (conf->set_size), initial_set)) + continue; + CPU_OR_S (CPU_ALLOC_SIZE (conf->set_size), + scratch_set, scratch_set, other_threads[cpu].seen_set); + CPU_FREE (other_threads[cpu].seen_set); + } + printf ("info: Other threads ran on %d CPU(s)\n", + CPU_COUNT_S (CPU_ALLOC_SIZE (conf->set_size), scratch_set));; + + + pthread_attr_destroy (&attr); + CPU_FREE (scratch_set); + CPU_FREE (initial_set); + free (pinned_threads); + free (other_threads); + return failed == 0; +} |