diff options
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | modules/pthread-mutex-tests | 14 | ||||
| -rw-r--r-- | tests/test-pthread-mutex.c | 524 |
3 files changed, 545 insertions, 0 deletions
@@ -1,5 +1,12 @@ 2019-07-14 Bruno Haible <bruno@clisp.org> + pthread-mutex: Add tests. + * tests/test-pthread-mutex.c: New file, based on tests/test-lock.c and + tests/test-mtx.c. + * modules/pthread-mutex-tests: New file. + +2019-07-14 Bruno Haible <bruno@clisp.org> + pthread-once: Add tests. * tests/test-pthread-once1.c: New file, based on tests/test-once.c and tests/test-call_once.c. diff --git a/modules/pthread-mutex-tests b/modules/pthread-mutex-tests new file mode 100644 index 0000000000..050d506b0e --- /dev/null +++ b/modules/pthread-mutex-tests @@ -0,0 +1,14 @@ +Files: +tests/test-pthread-mutex.c +tests/macros.h + +Depends-on: +pthread-thread +sched_yield + +configure.ac: + +Makefile.am: +TESTS += test-pthread-mutex +check_PROGRAMS += test-pthread-mutex +test_pthread_mutex_LDADD = $(LDADD) @LIBMULTITHREAD@ @YIELD_LIB@ diff --git a/tests/test-pthread-mutex.c b/tests/test-pthread-mutex.c new file mode 100644 index 0000000000..3ea0df6edc --- /dev/null +++ b/tests/test-pthread-mutex.c @@ -0,0 +1,524 @@ +/* Test of locking in multithreaded situations. + Copyright (C) 2005, 2008-2019 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by Bruno Haible <bruno@clisp.org>, 2005. */ + +#include <config.h> + +#if USE_POSIX_THREADS || USE_WINDOWS_THREADS + +/* Whether to enable locking. + Uncomment this to get a test program without locking, to verify that + it crashes. */ +#define ENABLE_LOCKING 1 + +/* Which tests to perform. + Uncomment some of these, to verify that all tests crash if no locking + is enabled. */ +#define DO_TEST_LOCK 1 +#define DO_TEST_RECURSIVE_LOCK 1 + +/* Whether to help the scheduler through explicit sched_yield(). + Uncomment this to see if the operating system has a fair scheduler. */ +#define EXPLICIT_YIELD 1 + +/* Whether to use 'volatile' on some variables that communicate information + between threads. If set to 0, a semaphore or a lock is used to protect + these variables. If set to 1, 'volatile' is used; this is theoretically + equivalent but can lead to much slower execution (e.g. 30x slower total + run time on a 40-core machine), because 'volatile' does not imply any + synchronization/communication between different CPUs. */ +#define USE_VOLATILE 0 + +#if USE_POSIX_THREADS && HAVE_SEMAPHORE_H +/* Whether to use a semaphore to communicate information between threads. + If set to 0, a lock is used. If set to 1, a semaphore is used. + Uncomment this to reduce the dependencies of this test. */ +# define USE_SEMAPHORE 1 +/* Mac OS X provides only named semaphores (sem_open); its facility for + unnamed semaphores (sem_init) does not work. */ +# if defined __APPLE__ && defined __MACH__ +# define USE_NAMED_SEMAPHORE 1 +# else +# define USE_UNNAMED_SEMAPHORE 1 +# endif +#endif + +/* Whether to print debugging messages. */ +#define ENABLE_DEBUGGING 0 + +/* Number of simultaneous threads. */ +#define THREAD_COUNT 10 + +/* Number of operations performed in each thread. + This is quite high, because with a smaller count, say 5000, we often get + an "OK" result even without ENABLE_LOCKING (on Linux/x86). */ +#define REPEAT_COUNT 50000 + +#include <pthread.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#if EXPLICIT_YIELD +# include <sched.h> +#endif + +#if USE_SEMAPHORE +# include <errno.h> +# include <fcntl.h> +# include <semaphore.h> +# include <unistd.h> +#endif + +#if HAVE_DECL_ALARM +# include <signal.h> +# include <unistd.h> +#endif + +#include "macros.h" + +#if ENABLE_DEBUGGING +# define dbgprintf printf +#else +# define dbgprintf if (0) printf +#endif + +#if EXPLICIT_YIELD +# define yield() sched_yield () +#else +# define yield() +#endif + +#if USE_VOLATILE +struct atomic_int { + volatile int value; +}; +static void +init_atomic_int (struct atomic_int *ai) +{ +} +static int +get_atomic_int_value (struct atomic_int *ai) +{ + return ai->value; +} +static void +set_atomic_int_value (struct atomic_int *ai, int new_value) +{ + ai->value = new_value; +} +#elif USE_SEMAPHORE +/* This atomic_int implementation can only support the values 0 and 1. + It is initially 0 and can be set to 1 only once. */ +# if USE_UNNAMED_SEMAPHORE +struct atomic_int { + sem_t semaphore; +}; +#define atomic_int_semaphore(ai) (&(ai)->semaphore) +static void +init_atomic_int (struct atomic_int *ai) +{ + sem_init (&ai->semaphore, 0, 0); +} +# endif +# if USE_NAMED_SEMAPHORE +struct atomic_int { + sem_t *semaphore; +}; +#define atomic_int_semaphore(ai) ((ai)->semaphore) +static void +init_atomic_int (struct atomic_int *ai) +{ + sem_t *s; + unsigned int count; + for (count = 0; ; count++) + { + char name[80]; + /* Use getpid() in the name, so that different processes running at the + same time will not interfere. Use ai in the name, so that different + atomic_int in the same process will not interfere. Use a count in + the name, so that even in the (unlikely) case that a semaphore with + the specified name already exists, we can try a different name. */ + sprintf (name, "test-lock-%lu-%p-%u", + (unsigned long) getpid (), ai, count); + s = sem_open (name, O_CREAT | O_EXCL, 0600, 0); + if (s == SEM_FAILED) + { + if (errno == EEXIST) + /* Retry with a different name. */ + continue; + else + { + perror ("sem_open failed"); + abort (); + } + } + else + { + /* Try not to leave a semaphore hanging around on the file system + eternally, if we can avoid it. */ + sem_unlink (name); + break; + } + } + ai->semaphore = s; +} +# endif +static int +get_atomic_int_value (struct atomic_int *ai) +{ + if (sem_trywait (atomic_int_semaphore (ai)) == 0) + { + if (sem_post (atomic_int_semaphore (ai))) + abort (); + return 1; + } + else if (errno == EAGAIN) + return 0; + else + abort (); +} +static void +set_atomic_int_value (struct atomic_int *ai, int new_value) +{ + if (new_value == 0) + /* It's already initialized with 0. */ + return; + /* To set the value 1: */ + if (sem_post (atomic_int_semaphore (ai))) + abort (); +} +#else +struct atomic_int { + pthread_mutex_t lock; + int value; +}; +static void +init_atomic_int (struct atomic_int *ai) +{ + pthread_mutexattr_t attr; + + ASSERT (pthread_mutexattr_init (&attr) == 0); + ASSERT (pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_NORMAL) == 0); + ASSERT (pthread_mutex_init (&ai->lock, &attr) == 0); + ASSERT (pthread_mutexattr_destroy (&attr) == 0); +} +static int +get_atomic_int_value (struct atomic_int *ai) +{ + ASSERT (pthread_mutex_lock (&ai->lock) == 0); + int ret = ai->value; + ASSERT (pthread_mutex_unlock (&ai->lock) == 0); + return ret; +} +static void +set_atomic_int_value (struct atomic_int *ai, int new_value) +{ + ASSERT (pthread_mutex_lock (&ai->lock) == 0); + ai->value = new_value; + ASSERT (pthread_mutex_unlock (&ai->lock) == 0); +} +#endif + +/* Returns a reference to the current thread as a pointer, for debugging. */ +#if defined __MVS__ + /* On IBM z/OS, pthread_t is a struct with an 8-byte '__' field. + The first three bytes of this field appear to uniquely identify a + pthread_t, though not necessarily representing a pointer. */ +# define pthread_self_pointer() (*((void **) pthread_self ().__)) +#else +# define pthread_self_pointer() ((void *) (uintptr_t) pthread_self ()) +#endif + +#define ACCOUNT_COUNT 4 + +static int account[ACCOUNT_COUNT]; + +static int +random_account (void) +{ + return ((unsigned int) rand () >> 3) % ACCOUNT_COUNT; +} + +static void +check_accounts (void) +{ + int i, sum; + + sum = 0; + for (i = 0; i < ACCOUNT_COUNT; i++) + sum += account[i]; + if (sum != ACCOUNT_COUNT * 1000) + abort (); +} + + +/* ------------------- Test normal (non-recursive) locks ------------------- */ + +/* Test normal locks by having several bank accounts and several threads + which shuffle around money between the accounts and another thread + checking that all the money is still there. */ + +static pthread_mutex_t my_lock; + +static void * +lock_mutator_thread (void *arg) +{ + int repeat; + + for (repeat = REPEAT_COUNT; repeat > 0; repeat--) + { + int i1, i2, value; + + dbgprintf ("Mutator %p before lock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_lock (&my_lock) == 0); + dbgprintf ("Mutator %p after lock\n", pthread_self_pointer ()); + + i1 = random_account (); + i2 = random_account (); + value = ((unsigned int) rand () >> 3) % 10; + account[i1] += value; + account[i2] -= value; + + dbgprintf ("Mutator %p before unlock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_unlock (&my_lock) == 0); + dbgprintf ("Mutator %p after unlock\n", pthread_self_pointer ()); + + dbgprintf ("Mutator %p before check lock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_lock (&my_lock) == 0); + check_accounts (); + ASSERT (pthread_mutex_unlock (&my_lock) == 0); + dbgprintf ("Mutator %p after check unlock\n", pthread_self_pointer ()); + + yield (); + } + + dbgprintf ("Mutator %p dying.\n", pthread_self_pointer ()); + return NULL; +} + +static struct atomic_int lock_checker_done; + +static void * +lock_checker_thread (void *arg) +{ + while (get_atomic_int_value (&lock_checker_done) == 0) + { + dbgprintf ("Checker %p before check lock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_lock (&my_lock) == 0); + check_accounts (); + ASSERT (pthread_mutex_unlock (&my_lock) == 0); + dbgprintf ("Checker %p after check unlock\n", pthread_self_pointer ()); + + yield (); + } + + dbgprintf ("Checker %p dying.\n", pthread_self_pointer ()); + return NULL; +} + +static void +test_pthread_mutex_normal (void) +{ + int i; + pthread_t checkerthread; + pthread_t threads[THREAD_COUNT]; + + /* Initialization. */ + for (i = 0; i < ACCOUNT_COUNT; i++) + account[i] = 1000; + init_atomic_int (&lock_checker_done); + set_atomic_int_value (&lock_checker_done, 0); + + /* Spawn the threads. */ + ASSERT (pthread_create (&checkerthread, NULL, lock_checker_thread, NULL) + == 0); + for (i = 0; i < THREAD_COUNT; i++) + ASSERT (pthread_create (&threads[i], NULL, lock_mutator_thread, NULL) == 0); + + /* Wait for the threads to terminate. */ + for (i = 0; i < THREAD_COUNT; i++) + ASSERT (pthread_join (threads[i], NULL) == 0); + set_atomic_int_value (&lock_checker_done, 1); + ASSERT (pthread_join (checkerthread, NULL) == 0); + check_accounts (); +} + + +/* -------------------------- Test recursive locks -------------------------- */ + +/* Test recursive locks by having several bank accounts and several threads + which shuffle around money between the accounts (recursively) and another + thread checking that all the money is still there. */ + +static pthread_mutex_t my_reclock; + +static void +recshuffle (void) +{ + int i1, i2, value; + + dbgprintf ("Mutator %p before lock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_lock (&my_reclock) == 0); + dbgprintf ("Mutator %p after lock\n", pthread_self_pointer ()); + + i1 = random_account (); + i2 = random_account (); + value = ((unsigned int) rand () >> 3) % 10; + account[i1] += value; + account[i2] -= value; + + /* Recursive with probability 0.5. */ + if (((unsigned int) rand () >> 3) % 2) + recshuffle (); + + dbgprintf ("Mutator %p before unlock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_unlock (&my_reclock) == 0); + dbgprintf ("Mutator %p after unlock\n", pthread_self_pointer ()); +} + +static void * +reclock_mutator_thread (void *arg) +{ + int repeat; + + for (repeat = REPEAT_COUNT; repeat > 0; repeat--) + { + recshuffle (); + + dbgprintf ("Mutator %p before check lock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_lock (&my_reclock) == 0); + check_accounts (); + ASSERT (pthread_mutex_unlock (&my_reclock) == 0); + dbgprintf ("Mutator %p after check unlock\n", pthread_self_pointer ()); + + yield (); + } + + dbgprintf ("Mutator %p dying.\n", pthread_self_pointer ()); + return NULL; +} + +static struct atomic_int reclock_checker_done; + +static void * +reclock_checker_thread (void *arg) +{ + while (get_atomic_int_value (&reclock_checker_done) == 0) + { + dbgprintf ("Checker %p before check lock\n", pthread_self_pointer ()); + ASSERT (pthread_mutex_lock (&my_reclock) == 0); + check_accounts (); + ASSERT (pthread_mutex_unlock (&my_reclock) == 0); + dbgprintf ("Checker %p after check unlock\n", pthread_self_pointer ()); + + yield (); + } + + dbgprintf ("Checker %p dying.\n", pthread_self_pointer ()); + return NULL; +} + +static void +test_pthread_mutex_recursive (void) +{ + int i; + pthread_t checkerthread; + pthread_t threads[THREAD_COUNT]; + + /* Initialization. */ + for (i = 0; i < ACCOUNT_COUNT; i++) + account[i] = 1000; + init_atomic_int (&reclock_checker_done); + set_atomic_int_value (&reclock_checker_done, 0); + + /* Spawn the threads. */ + ASSERT (pthread_create (&checkerthread, NULL, reclock_checker_thread, NULL) + == 0); + for (i = 0; i < THREAD_COUNT; i++) + ASSERT (pthread_create (&threads[i], NULL, reclock_mutator_thread, NULL) + == 0); + + /* Wait for the threads to terminate. */ + for (i = 0; i < THREAD_COUNT; i++) + ASSERT (pthread_join (threads[i], NULL) == 0); + set_atomic_int_value (&reclock_checker_done, 1); + ASSERT (pthread_join (checkerthread, NULL) == 0); + check_accounts (); +} + + +/* -------------------------------------------------------------------------- */ + +int +main () +{ +#if HAVE_DECL_ALARM + /* Declare failure if test takes too long, by using default abort + caused by SIGALRM. */ + int alarm_value = 600; + signal (SIGALRM, SIG_DFL); + alarm (alarm_value); +#endif + + { + pthread_mutexattr_t attr; + + ASSERT (pthread_mutexattr_init (&attr) == 0); + ASSERT (pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_NORMAL) == 0); + ASSERT (pthread_mutex_init (&my_lock, &attr) == 0); + ASSERT (pthread_mutexattr_destroy (&attr) == 0); + } + + { + pthread_mutexattr_t attr; + + ASSERT (pthread_mutexattr_init (&attr) == 0); + ASSERT (pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE) == 0); + ASSERT (pthread_mutex_init (&my_reclock, &attr) == 0); + ASSERT (pthread_mutexattr_destroy (&attr) == 0); + } + +#if DO_TEST_LOCK + printf ("Starting test_pthread_mutex_normal ..."); fflush (stdout); + test_pthread_mutex_normal (); + printf (" OK\n"); fflush (stdout); +#endif +#if DO_TEST_RECURSIVE_LOCK + printf ("Starting test_pthread_mutex_recursive ..."); fflush (stdout); + test_pthread_mutex_recursive (); + printf (" OK\n"); fflush (stdout); +#endif + + return 0; +} + +#else + +/* No multithreading available. */ + +#include <stdio.h> + +int +main () +{ + fputs ("Skipping test: multithreading not enabled\n", stderr); + return 77; +} + +#endif |