/* Test of locking in multithreaded situations. Copyright (C) 2005, 2008-2012 Free Software Foundation, Inc. This program 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. 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this program. If not, see . */ /* Written by Bruno Haible , 2005. */ #include #if USE_POSIX_THREADS || USE_SOLARIS_THREADS || USE_PTH_THREADS || USE_WINDOWS_THREADS #if USE_POSIX_THREADS # define TEST_POSIX_THREADS 1 #endif #if USE_SOLARIS_THREADS # define TEST_SOLARIS_THREADS 1 #endif #if USE_PTH_THREADS # define TEST_PTH_THREADS 1 #endif #if USE_WINDOWS_THREADS # define TEST_WINDOWS_THREADS 1 #endif /* 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_RWLOCK 1 #define DO_TEST_RECURSIVE_LOCK 1 #define DO_TEST_ONCE 1 /* Whether to help the scheduler through explicit yield(). Uncomment this to see if the operating system has a fair scheduler. */ #define EXPLICIT_YIELD 1 /* 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 #include #include #if !ENABLE_LOCKING # undef USE_POSIX_THREADS # undef USE_SOLARIS_THREADS # undef USE_PTH_THREADS # undef USE_WINDOWS_THREADS #endif #include "lock.h" #if ENABLE_DEBUGGING # define dbgprintf printf #else # define dbgprintf if (0) printf #endif #if TEST_POSIX_THREADS # include # include typedef pthread_t gl_thread_t; static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg) { pthread_t thread; if (pthread_create (&thread, NULL, func, arg) != 0) abort (); return thread; } static inline void gl_thread_join (gl_thread_t thread, void **retvalp) { if (pthread_join (thread, retvalp) != 0) abort (); } static inline void gl_thread_yield (void) { sched_yield (); } static inline void * gl_thread_self_pointer (void) { # ifdef PTW32_VERSION return pthread_self ().p; # else return (void *) pthread_self (); # endif } #endif #if TEST_PTH_THREADS # include typedef pth_t gl_thread_t; static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg) { pth_t thread = pth_spawn (NULL, func, arg); if (thread == NULL) abort (); return thread; } static inline void gl_thread_join (gl_thread_t thread, void **retvalp) { if (!pth_join (thread, retvalp)) abort (); } static inline void gl_thread_yield (void) { pth_yield (NULL); } static inline void * gl_thread_self_pointer (void) { return pth_self (); } #endif #if TEST_SOLARIS_THREADS # include typedef thread_t gl_thread_t; static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg) { thread_t thread; if (thr_create (NULL, 0, func, arg, 0, &thread) != 0) abort (); return thread; } static inline void gl_thread_join (gl_thread_t thread, void **retvalp) { if (thr_join (thread, NULL, retvalp) != 0) abort (); } static inline void gl_thread_yield (void) { thr_yield (); } static inline void * gl_thread_self_pointer (void) { return (void *) thr_self (); } #endif #if TEST_WINDOWS_THREADS # include typedef HANDLE gl_thread_t; /* Use a wrapper function, instead of adding WINAPI through a cast. */ struct wrapper_args { void * (*func) (void *); void *arg; }; static DWORD WINAPI wrapper_func (void *varg) { struct wrapper_args *warg = (struct wrapper_args *)varg; void * (*func) (void *) = warg->func; void *arg = warg->arg; free (warg); func (arg); return 0; } static inline gl_thread_t gl_thread_create (void * (*func) (void *), void *arg) { struct wrapper_args *warg = (struct wrapper_args *) malloc (sizeof (struct wrapper_args)); if (warg == NULL) abort (); warg->func = func; warg->arg = arg; { DWORD thread_id; HANDLE thread = CreateThread (NULL, 100000, wrapper_func, warg, 0, &thread_id); if (thread == NULL) abort (); return thread; } } static inline void gl_thread_join (gl_thread_t thread, void **retvalp) { (void) retvalp; if (WaitForSingleObject (thread, INFINITE) == WAIT_FAILED) abort (); if (!CloseHandle (thread)) abort (); } static inline void gl_thread_yield (void) { Sleep (0); } static inline void * gl_thread_self_pointer (void) { return (void *) GetCurrentThreadId (); } #endif #if EXPLICIT_YIELD # define yield() gl_thread_yield () #else # define yield() #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. */ gl_lock_define_initialized(static, 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", gl_thread_self_pointer ()); gl_lock_lock (my_lock); dbgprintf ("Mutator %p after lock\n", gl_thread_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", gl_thread_self_pointer ()); gl_lock_unlock (my_lock); dbgprintf ("Mutator %p after unlock\n", gl_thread_self_pointer ()); dbgprintf ("Mutator %p before check lock\n", gl_thread_self_pointer ()); gl_lock_lock (my_lock); check_accounts (); gl_lock_unlock (my_lock); dbgprintf ("Mutator %p after check unlock\n", gl_thread_self_pointer ()); yield (); } dbgprintf ("Mutator %p dying.\n", gl_thread_self_pointer ()); return NULL; } static volatile int lock_checker_done; static void * lock_checker_thread (void *arg) { while (!lock_checker_done) { dbgprintf ("Checker %p before check lock\n", gl_thread_self_pointer ()); gl_lock_lock (my_lock); check_accounts (); gl_lock_unlock (my_lock); dbgprintf ("Checker %p after check unlock\n", gl_thread_self_pointer ()); yield (); } dbgprintf ("Checker %p dying.\n", gl_thread_self_pointer ()); return NULL; } static void test_lock (void) { int i; gl_thread_t checkerthread; gl_thread_t threads[THREAD_COUNT]; /* Initialization. */ for (i = 0; i < ACCOUNT_COUNT; i++) account[i] = 1000; lock_checker_done = 0; /* Spawn the threads. */ checkerthread = gl_thread_create (lock_checker_thread, NULL); for (i = 0; i < THREAD_COUNT; i++) threads[i] = gl_thread_create (lock_mutator_thread, NULL); /* Wait for the threads to terminate. */ for (i = 0; i < THREAD_COUNT; i++) gl_thread_join (threads[i], NULL); lock_checker_done = 1; gl_thread_join (checkerthread, NULL); check_accounts (); } /* ----------------- Test read-write (non-recursive) locks ----------------- */ /* Test read-write locks by having several bank accounts and several threads which shuffle around money between the accounts and several other threads that check that all the money is still there. */ gl_rwlock_define_initialized(static, my_rwlock) static void * rwlock_mutator_thread (void *arg) { int repeat; for (repeat = REPEAT_COUNT; repeat > 0; repeat--) { int i1, i2, value; dbgprintf ("Mutator %p before wrlock\n", gl_thread_self_pointer ()); gl_rwlock_wrlock (my_rwlock); dbgprintf ("Mutator %p after wrlock\n", gl_thread_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", gl_thread_self_pointer ()); gl_rwlock_unlock (my_rwlock); dbgprintf ("Mutator %p after unlock\n", gl_thread_self_pointer ()); yield (); } dbgprintf ("Mutator %p dying.\n", gl_thread_self_pointer ()); return NULL; } static volatile int rwlock_checker_done; static void * rwlock_checker_thread (void *arg) { while (!rwlock_checker_done) { dbgprintf ("Checker %p before check rdlock\n", gl_thread_self_pointer ()); gl_rwlock_rdlock (my_rwlock); check_accounts (); gl_rwlock_unlock (my_rwlock); dbgprintf ("Checker %p after check unlock\n", gl_thread_self_pointer ()); yield (); } dbgprintf ("Checker %p dying.\n", gl_thread_self_pointer ()); return NULL; } static void test_rwlock (void) { int i; gl_thread_t checkerthreads[THREAD_COUNT]; gl_thread_t threads[THREAD_COUNT]; /* Initialization. */ for (i = 0; i < ACCOUNT_COUNT; i++) account[i] = 1000; rwlock_checker_done = 0; /* Spawn the threads. */ for (i = 0; i < THREAD_COUNT; i++) checkerthreads[i] = gl_thread_create (rwlock_checker_thread, NULL); for (i = 0; i < THREAD_COUNT; i++) threads[i] = gl_thread_create (rwlock_mutator_thread, NULL); /* Wait for the threads to terminate. */ for (i = 0; i < THREAD_COUNT; i++) gl_thread_join (threads[i], NULL); rwlock_checker_done = 1; for (i = 0; i < THREAD_COUNT; i++) gl_thread_join (checkerthreads[i], NULL); 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. */ gl_recursive_lock_define_initialized(static, my_reclock) static void recshuffle (void) { int i1, i2, value; dbgprintf ("Mutator %p before lock\n", gl_thread_self_pointer ()); gl_recursive_lock_lock (my_reclock); dbgprintf ("Mutator %p after lock\n", gl_thread_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", gl_thread_self_pointer ()); gl_recursive_lock_unlock (my_reclock); dbgprintf ("Mutator %p after unlock\n", gl_thread_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", gl_thread_self_pointer ()); gl_recursive_lock_lock (my_reclock); check_accounts (); gl_recursive_lock_unlock (my_reclock); dbgprintf ("Mutator %p after check unlock\n", gl_thread_self_pointer ()); yield (); } dbgprintf ("Mutator %p dying.\n", gl_thread_self_pointer ()); return NULL; } static volatile int reclock_checker_done; static void * reclock_checker_thread (void *arg) { while (!reclock_checker_done) { dbgprintf ("Checker %p before check lock\n", gl_thread_self_pointer ()); gl_recursive_lock_lock (my_reclock); check_accounts (); gl_recursive_lock_unlock (my_reclock); dbgprintf ("Checker %p after check unlock\n", gl_thread_self_pointer ()); yield (); } dbgprintf ("Checker %p dying.\n", gl_thread_self_pointer ()); return NULL; } static void test_recursive_lock (void) { int i; gl_thread_t checkerthread; gl_thread_t threads[THREAD_COUNT]; /* Initialization. */ for (i = 0; i < ACCOUNT_COUNT; i++) account[i] = 1000; reclock_checker_done = 0; /* Spawn the threads. */ checkerthread = gl_thread_create (reclock_checker_thread, NULL); for (i = 0; i < THREAD_COUNT; i++) threads[i] = gl_thread_create (reclock_mutator_thread, NULL); /* Wait for the threads to terminate. */ for (i = 0; i < THREAD_COUNT; i++) gl_thread_join (threads[i], NULL); reclock_checker_done = 1; gl_thread_join (checkerthread, NULL); check_accounts (); } /* ------------------------ Test once-only execution ------------------------ */ /* Test once-only execution by having several threads attempt to grab a once-only task simultaneously (triggered by releasing a read-write lock). */ gl_once_define(static, fresh_once) static int ready[THREAD_COUNT]; static gl_lock_t ready_lock[THREAD_COUNT]; #if ENABLE_LOCKING static gl_rwlock_t fire_signal[REPEAT_COUNT]; #else static volatile int fire_signal_state; #endif static gl_once_t once_control; static int performed; gl_lock_define_initialized(static, performed_lock) static void once_execute (void) { gl_lock_lock (performed_lock); performed++; gl_lock_unlock (performed_lock); } static void * once_contender_thread (void *arg) { int id = (int) (long) arg; int repeat; for (repeat = 0; repeat <= REPEAT_COUNT; repeat++) { /* Tell the main thread that we're ready. */ gl_lock_lock (ready_lock[id]); ready[id] = 1; gl_lock_unlock (ready_lock[id]); if (repeat == REPEAT_COUNT) break; dbgprintf ("Contender %p waiting for signal for round %d\n", gl_thread_self_pointer (), repeat); #if ENABLE_LOCKING /* Wait for the signal to go. */ gl_rwlock_rdlock (fire_signal[repeat]); /* And don't hinder the others (if the scheduler is unfair). */ gl_rwlock_unlock (fire_signal[repeat]); #else /* Wait for the signal to go. */ while (fire_signal_state <= repeat) yield (); #endif dbgprintf ("Contender %p got the signal for round %d\n", gl_thread_self_pointer (), repeat); /* Contend for execution. */ gl_once (once_control, once_execute); } return NULL; } static void test_once (void) { int i, repeat; gl_thread_t threads[THREAD_COUNT]; /* Initialize all variables. */ for (i = 0; i < THREAD_COUNT; i++) { ready[i] = 0; gl_lock_init (ready_lock[i]); } #if ENABLE_LOCKING for (i = 0; i < REPEAT_COUNT; i++) gl_rwlock_init (fire_signal[i]); #else fire_signal_state = 0; #endif /* Block all fire_signals. */ for (i = REPEAT_COUNT-1; i >= 0; i--) gl_rwlock_wrlock (fire_signal[i]); /* Spawn the threads. */ for (i = 0; i < THREAD_COUNT; i++) threads[i] = gl_thread_create (once_contender_thread, (void *) (long) i); for (repeat = 0; repeat <= REPEAT_COUNT; repeat++) { /* Wait until every thread is ready. */ dbgprintf ("Main thread before synchronizing for round %d\n", repeat); for (;;) { int ready_count = 0; for (i = 0; i < THREAD_COUNT; i++) { gl_lock_lock (ready_lock[i]); ready_count += ready[i]; gl_lock_unlock (ready_lock[i]); } if (ready_count == THREAD_COUNT) break; yield (); } dbgprintf ("Main thread after synchronizing for round %d\n", repeat); if (repeat > 0) { /* Check that exactly one thread executed the once_execute() function. */ if (performed != 1) abort (); } if (repeat == REPEAT_COUNT) break; /* Preparation for the next round: Initialize once_control. */ memcpy (&once_control, &fresh_once, sizeof (gl_once_t)); /* Preparation for the next round: Reset the performed counter. */ performed = 0; /* Preparation for the next round: Reset the ready flags. */ for (i = 0; i < THREAD_COUNT; i++) { gl_lock_lock (ready_lock[i]); ready[i] = 0; gl_lock_unlock (ready_lock[i]); } /* Signal all threads simultaneously. */ dbgprintf ("Main thread giving signal for round %d\n", repeat); #if ENABLE_LOCKING gl_rwlock_unlock (fire_signal[repeat]); #else fire_signal_state = repeat + 1; #endif } /* Wait for the threads to terminate. */ for (i = 0; i < THREAD_COUNT; i++) gl_thread_join (threads[i], NULL); } /* -------------------------------------------------------------------------- */ int main () { #if TEST_PTH_THREADS if (!pth_init ()) abort (); #endif #if DO_TEST_LOCK printf ("Starting test_lock ..."); fflush (stdout); test_lock (); printf (" OK\n"); fflush (stdout); #endif #if DO_TEST_RWLOCK printf ("Starting test_rwlock ..."); fflush (stdout); test_rwlock (); printf (" OK\n"); fflush (stdout); #endif #if DO_TEST_RECURSIVE_LOCK printf ("Starting test_recursive_lock ..."); fflush (stdout); test_recursive_lock (); printf (" OK\n"); fflush (stdout); #endif #if DO_TEST_ONCE printf ("Starting test_once ..."); fflush (stdout); test_once (); printf (" OK\n"); fflush (stdout); #endif return 0; } #else /* No multithreading available. */ #include int main () { fputs ("Skipping test: multithreading not enabled\n", stderr); return 77; } #endif