From 074d8438a30f7da8ae12eb94caff69c37fb576bd Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Wed, 30 Sep 2009 22:29:44 -0400 Subject: [PATCH] Add test for rcu_assign_pointer() Signed-off-by: Mathieu Desnoyers --- tests/Makefile.inc | 8 +- tests/test_urcu_assign.c | 431 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 438 insertions(+), 1 deletion(-) create mode 100644 tests/test_urcu_assign.c diff --git a/tests/Makefile.inc b/tests/Makefile.inc index 20eef58..78a6092 100644 --- a/tests/Makefile.inc +++ b/tests/Makefile.inc @@ -24,7 +24,7 @@ all: test_urcu test_urcu_dynamic_link test_urcu_timing \ urcutorture-yield test_mutex test_looplen test_urcu_gc \ test_urcu_gc_mb test_qsbr_gc test_qsbr_lgc test_urcu_lgc \ test_urcu_lgc_mb test_qsbr_dynamic_link test_urcu_mb_defer \ - test_uatomic + test_uatomic test_urcu_assign test_urcu_assign_dynamic_link api.h: ${APIHEADER} cp -f ${APIHEADER} api.h @@ -42,6 +42,12 @@ test_urcu_gc: test_urcu_gc.c ${URCU_SIGNAL} test_urcu_lgc: test_urcu_gc.c ${URCU_SIGNAL} $(CC) -DTEST_LOCAL_GC ${CFLAGS} $(LDFLAGS) -o $@ $(SRC_DEP) +test_urcu_assign: test_urcu_assign.c ${URCU_SIGNAL} + $(CC) ${CFLAGS} $(LDFLAGS) -o $@ $(SRC_DEP) + +test_urcu_assign_dynamic_link: test_urcu.c ${URCU_SIGNAL} + $(CC) ${CFLAGS} -DDYNAMIC_LINK_TEST $(LDFLAGS) -o $@ $(SRC_DEP) + test_urcu_mb: test_urcu.c ${URCU_MB} $(CC) -DURCU_MB ${CFLAGS} $(LDFLAGS) -o $@ $(SRC_DEP) diff --git a/tests/test_urcu_assign.c b/tests/test_urcu_assign.c new file mode 100644 index 0000000..1b8f618 --- /dev/null +++ b/tests/test_urcu_assign.c @@ -0,0 +1,431 @@ +/* + * test_urcu_assign.c + * + * Userspace RCU library - test program + * + * Copyright February 2009 - Mathieu Desnoyers + * + * 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 2 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, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* hardcoded number of CPUs */ +#define NR_CPUS 16384 + +#if defined(_syscall0) +_syscall0(pid_t, gettid) +#elif defined(__NR_gettid) +static inline pid_t gettid(void) +{ + return syscall(__NR_gettid); +} +#else +#warning "use pid as tid" +static inline pid_t gettid(void) +{ + return getpid(); +} +#endif + +#ifndef DYNAMIC_LINK_TEST +#define _LGPL_SOURCE +#else +#define debug_yield_read() +#endif +#include + +struct test_array { + int a; +}; + +static volatile int test_go, test_stop; + +static unsigned long wdelay; + +static struct test_array *test_rcu_pointer; + +static unsigned long duration; + +/* read-side C.S. duration, in loops */ +static unsigned long rduration; + +static inline void loop_sleep(unsigned long l) +{ + while(l-- != 0) + cpu_relax(); +} + +static int verbose_mode; + +#define printf_verbose(fmt, args...) \ + do { \ + if (verbose_mode) \ + printf(fmt, args); \ + } while (0) + +static unsigned int cpu_affinities[NR_CPUS]; +static unsigned int next_aff = 0; +static int use_affinity = 0; + +pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER; + +static void set_affinity(void) +{ + cpu_set_t mask; + int cpu; + int ret; + + if (!use_affinity) + return; + + ret = pthread_mutex_lock(&affinity_mutex); + if (ret) { + perror("Error in pthread mutex lock"); + exit(-1); + } + cpu = cpu_affinities[next_aff++]; + ret = pthread_mutex_unlock(&affinity_mutex); + if (ret) { + perror("Error in pthread mutex unlock"); + exit(-1); + } + CPU_ZERO(&mask); + CPU_SET(cpu, &mask); + sched_setaffinity(0, sizeof(mask), &mask); +} + +/* + * returns 0 if test should end. + */ +static int test_duration_write(void) +{ + return !test_stop; +} + +static int test_duration_read(void) +{ + return !test_stop; +} + +static unsigned long long __thread nr_writes; +static unsigned long long __thread nr_reads; + +static unsigned int nr_readers; +static unsigned int nr_writers; + +pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER; + +void rcu_copy_mutex_lock(void) +{ + int ret; + ret = pthread_mutex_lock(&rcu_copy_mutex); + if (ret) { + perror("Error in pthread mutex lock"); + exit(-1); + } +} + +void rcu_copy_mutex_unlock(void) +{ + int ret; + + ret = pthread_mutex_unlock(&rcu_copy_mutex); + if (ret) { + perror("Error in pthread mutex unlock"); + exit(-1); + } +} + +/* + * malloc/free are reusing memory areas too quickly, which does not let us + * test races appropriately. Use a large circular array for allocations. + * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail. + */ +#define ARRAY_SIZE (1048576 * nr_writers) +#define ARRAY_POISON 0xDEADBEEF +static int array_index; +static struct test_array *test_array; + +static struct test_array *test_array_alloc(void) +{ + struct test_array *ret; + int index; + + rcu_copy_mutex_lock(); + index = array_index % ARRAY_SIZE; + assert(test_array[index].a == ARRAY_POISON || + test_array[index].a == 0); + ret = &test_array[index]; + array_index++; + if (array_index == ARRAY_SIZE) + array_index = 0; + rcu_copy_mutex_unlock(); + return ret; +} + +static void test_array_free(struct test_array *ptr) +{ + if (!ptr) + return; + rcu_copy_mutex_lock(); + ptr->a = ARRAY_POISON; + rcu_copy_mutex_unlock(); +} + +void *thr_reader(void *_count) +{ + unsigned long long *count = _count; + struct test_array *local_ptr; + + printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n", + "reader", pthread_self(), (unsigned long)gettid()); + + set_affinity(); + + rcu_register_thread(); + + while (!test_go) + { + } + smp_mb(); + + for (;;) { + rcu_read_lock(); + local_ptr = rcu_dereference(test_rcu_pointer); + debug_yield_read(); + if (local_ptr) + assert(local_ptr->a == 8); + if (unlikely(rduration)) + loop_sleep(rduration); + rcu_read_unlock(); + nr_reads++; + if (unlikely(!test_duration_read())) + break; + } + + rcu_unregister_thread(); + + *count = nr_reads; + printf_verbose("thread_end %s, thread id : %lx, tid %lu\n", + "reader", pthread_self(), (unsigned long)gettid()); + return ((void*)1); + +} + +void *thr_writer(void *_count) +{ + unsigned long long *count = _count; + struct test_array *new, *old; + + printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n", + "writer", pthread_self(), (unsigned long)gettid()); + + set_affinity(); + + while (!test_go) + { + } + smp_mb(); + + for (;;) { + new = test_array_alloc(); + new->a = 8; + rcu_copy_mutex_lock(); + old = test_rcu_pointer; + rcu_assign_pointer(test_rcu_pointer, new); + rcu_copy_mutex_unlock(); + synchronize_rcu(); + if (old) + old->a = 0; + test_array_free(old); + nr_writes++; + if (unlikely(!test_duration_write())) + break; + if (unlikely(wdelay)) + loop_sleep(wdelay); + } + + printf_verbose("thread_end %s, thread id : %lx, tid %lu\n", + "writer", pthread_self(), (unsigned long)gettid()); + *count = nr_writes; + return ((void*)2); +} + +void show_usage(int argc, char **argv) +{ + printf("Usage : %s nr_readers nr_writers duration (s)", argv[0]); +#ifdef DEBUG_YIELD + printf(" [-r] [-w] (yield reader and/or writer)"); +#endif + printf(" [-d delay] (writer period (us))"); + printf(" [-c duration] (reader C.S. duration (in loops))"); + printf(" [-v] (verbose output)"); + printf(" [-a cpu#] [-a cpu#]... (affinity)"); + printf("\n"); +} + +int main(int argc, char **argv) +{ + int err; + pthread_t *tid_reader, *tid_writer; + void *tret; + unsigned long long *count_reader, *count_writer; + unsigned long long tot_reads = 0, tot_writes = 0; + int i, a; + + if (argc < 4) { + show_usage(argc, argv); + return -1; + } + + err = sscanf(argv[1], "%u", &nr_readers); + if (err != 1) { + show_usage(argc, argv); + return -1; + } + + err = sscanf(argv[2], "%u", &nr_writers); + if (err != 1) { + show_usage(argc, argv); + return -1; + } + + err = sscanf(argv[3], "%lu", &duration); + if (err != 1) { + show_usage(argc, argv); + return -1; + } + + for (i = 4; i < argc; i++) { + if (argv[i][0] != '-') + continue; + switch (argv[i][1]) { +#ifdef DEBUG_YIELD + case 'r': + yield_active |= YIELD_READ; + break; + case 'w': + yield_active |= YIELD_WRITE; + break; +#endif + case 'a': + if (argc < i + 2) { + show_usage(argc, argv); + return -1; + } + a = atoi(argv[++i]); + cpu_affinities[next_aff++] = a; + use_affinity = 1; + printf_verbose("Adding CPU %d affinity\n", a); + break; + case 'c': + if (argc < i + 2) { + show_usage(argc, argv); + return -1; + } + rduration = atol(argv[++i]); + break; + case 'd': + if (argc < i + 2) { + show_usage(argc, argv); + return -1; + } + wdelay = atol(argv[++i]); + break; + case 'v': + verbose_mode = 1; + break; + } + } + + printf_verbose("running test for %lu seconds, %u readers, %u writers.\n", + duration, nr_readers, nr_writers); + printf_verbose("Writer delay : %lu loops.\n", wdelay); + printf_verbose("Reader duration : %lu loops.\n", rduration); + printf_verbose("thread %-6s, thread id : %lx, tid %lu\n", + "main", pthread_self(), (unsigned long)gettid()); + + test_array = malloc(sizeof(*test_array) * ARRAY_SIZE); + tid_reader = malloc(sizeof(*tid_reader) * nr_readers); + tid_writer = malloc(sizeof(*tid_writer) * nr_writers); + count_reader = malloc(sizeof(*count_reader) * nr_readers); + count_writer = malloc(sizeof(*count_writer) * nr_writers); + + next_aff = 0; + + for (i = 0; i < nr_readers; i++) { + err = pthread_create(&tid_reader[i], NULL, thr_reader, + &count_reader[i]); + if (err != 0) + exit(1); + } + for (i = 0; i < nr_writers; i++) { + err = pthread_create(&tid_writer[i], NULL, thr_writer, + &count_writer[i]); + if (err != 0) + exit(1); + } + + smp_mb(); + + test_go = 1; + + sleep(duration); + + test_stop = 1; + + for (i = 0; i < nr_readers; i++) { + err = pthread_join(tid_reader[i], &tret); + if (err != 0) + exit(1); + tot_reads += count_reader[i]; + } + for (i = 0; i < nr_writers; i++) { + err = pthread_join(tid_writer[i], &tret); + if (err != 0) + exit(1); + tot_writes += count_writer[i]; + } + + printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads, + tot_writes); + printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu " + "nr_writers %3u " + "wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n", + argv[0], duration, nr_readers, rduration, + nr_writers, wdelay, tot_reads, tot_writes, + tot_reads + tot_writes); + test_array_free(test_rcu_pointer); + free(test_array); + free(tid_reader); + free(tid_writer); + free(count_reader); + free(count_writer); + return 0; +} -- 2.34.1