wfstack test: test if number of push to empty vs pop_all match

Do same as wfcqueue: we can test if number of push to empty stack match
the number of pop_all that return non-empty stack.

Can be tested with:
./test_urcu_wfs 5 5 10 -w

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/tests/test_urcu_wfs.c b/tests/test_urcu_wfs.c
index e36b822569e6a821fe3ad8841a6c9d34801ddb66..1c852b9dd0abce809d5e7b679300673c88bbe469 100644 (file)
--- a/tests/test_urcu_wfs.c
+++ b/tests/test_urcu_wfs.c
@@ -80,7 +80,7 @@ static enum test_sync test_sync;
 
 static int test_force_sync;
 
-static volatile int test_go, test_stop;
+static volatile int test_go, test_stop_enqueue, test_stop_dequeue;
 
 static unsigned long rduration;
 
@@ -97,7 +97,8 @@ static inline void loop_sleep(unsigned long loops)
 
 static int verbose_mode;
 
-static int test_pop, test_pop_all;
+static int test_pop, test_pop_all, test_wait_empty;
+static int test_enqueue_stopped;
 
 #define printf_verbose(fmt, args...)           \
        do {                                    \
@@ -155,12 +156,12 @@ static void set_affinity(void)
  */
 static int test_duration_dequeue(void)
 {
-       return !test_stop;
+       return !test_stop_dequeue;
 }
 
 static int test_duration_enqueue(void)
 {
-       return !test_stop;
+       return !test_stop_enqueue;
 }
 
 static DEFINE_URCU_TLS(unsigned long long, nr_dequeues);
@@ -168,6 +169,8 @@ static DEFINE_URCU_TLS(unsigned long long, nr_enqueues);
 
 static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues);
 static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues);
+static DEFINE_URCU_TLS(unsigned long long, nr_empty_dest_enqueues);
+static DEFINE_URCU_TLS(unsigned long long, nr_pop_all);
 
 static unsigned int nr_enqueuers;
 static unsigned int nr_dequeuers;
@@ -177,6 +180,7 @@ static struct cds_wfs_stack s;
 static void *thr_enqueuer(void *_count)
 {
        unsigned long long *count = _count;
+       bool was_nonempty;
 
        printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
                        "enqueuer", (unsigned long) pthread_self(),
@@ -194,8 +198,10 @@ static void *thr_enqueuer(void *_count)
                if (!node)
                        goto fail;
                cds_wfs_node_init(node);
-               cds_wfs_push(&s, node);
+               was_nonempty = cds_wfs_push(&s, node);
                URCU_TLS(nr_successful_enqueues)++;
+               if (!was_nonempty)
+                       URCU_TLS(nr_empty_dest_enqueues)++;
 
                if (caa_unlikely(wdelay))
                        loop_sleep(wdelay);
@@ -205,13 +211,18 @@ fail:
                        break;
        }
 
+       uatomic_inc(&test_enqueue_stopped);
        count[0] = URCU_TLS(nr_enqueues);
        count[1] = URCU_TLS(nr_successful_enqueues);
+       count[2] = URCU_TLS(nr_empty_dest_enqueues);
        printf_verbose("enqueuer thread_end, thread id : %lx, tid %lu, "
-                      "enqueues %llu successful_enqueues %llu\n",
+                      "enqueues %llu successful_enqueues %llu, "
+                      "empty_dest_enqueues %llu\n",
                       pthread_self(),
                        (unsigned long) gettid(),
-                      URCU_TLS(nr_enqueues), URCU_TLS(nr_successful_enqueues));
+                      URCU_TLS(nr_enqueues),
+                      URCU_TLS(nr_successful_enqueues),
+                      URCU_TLS(nr_empty_dest_enqueues));
        return ((void*)1);
 
 }
@@ -244,6 +255,12 @@ static void do_test_pop_all(enum test_sync sync)
        if (sync == TEST_SYNC_MUTEX)
                cds_wfs_pop_unlock(&s);
 
+       /* Check if empty */
+       if (cds_wfs_first_blocking(head) == NULL)
+               return;
+
+       URCU_TLS(nr_pop_all)++;
+
        cds_wfs_for_each_blocking_safe(head, node, n) {
                free(node);
                URCU_TLS(nr_successful_dequeues)++;
@@ -290,12 +307,15 @@ static void *thr_dequeuer(void *_count)
        }
 
        printf_verbose("dequeuer thread_end, thread id : %lx, tid %lu, "
-                      "dequeues %llu, successful_dequeues %llu\n",
+                      "dequeues %llu, successful_dequeues %llu "
+                      "pop_all %llu\n",
                       pthread_self(),
                        (unsigned long) gettid(),
-                      URCU_TLS(nr_dequeues), URCU_TLS(nr_successful_dequeues));
+                      URCU_TLS(nr_dequeues), URCU_TLS(nr_successful_dequeues),
+                      URCU_TLS(nr_pop_all));
        count[0] = URCU_TLS(nr_dequeues);
        count[1] = URCU_TLS(nr_successful_dequeues);
+       count[2] = URCU_TLS(nr_pop_all);
        return ((void*)2);
 }
 
@@ -324,6 +344,7 @@ static void show_usage(int argc, char **argv)
        printf(" [-M] (use mutex external synchronization)");
        printf("      Note: default: no external synchronization used.");
        printf(" [-f] (force user-provided synchronization)");
+       printf(" [-w] Wait for dequeuer to empty stack");
        printf("\n");
 }
 
@@ -335,9 +356,11 @@ int main(int argc, char **argv)
        unsigned long long *count_enqueuer, *count_dequeuer;
        unsigned long long tot_enqueues = 0, tot_dequeues = 0;
        unsigned long long tot_successful_enqueues = 0,
-                          tot_successful_dequeues = 0;
+                          tot_successful_dequeues = 0,
+                          tot_empty_dest_enqueues = 0,
+                          tot_pop_all = 0;
        unsigned long long end_dequeues = 0;
-       int i, a;
+       int i, a, retval = 0;
 
        if (argc < 4) {
                show_usage(argc, argv);
@@ -402,6 +425,9 @@ int main(int argc, char **argv)
                case 'M':
                        test_sync = TEST_SYNC_MUTEX;
                        break;
+               case 'w':
+                       test_wait_empty = 1;
+                       break;
                case 'f':
                        test_force_sync = 1;
                        break;
@@ -434,6 +460,8 @@ int main(int argc, char **argv)
                printf_verbose("External sync: mutex.\n");
        else
                printf_verbose("External sync: none.\n");
+       if (test_wait_empty)
+               printf_verbose("Wait for dequeuers to empty stack.\n");
        printf_verbose("Writer delay : %lu loops.\n", rduration);
        printf_verbose("Reader duration : %lu loops.\n", wdelay);
        printf_verbose("thread %-6s, thread id : %lx, tid %lu\n",
@@ -442,21 +470,21 @@ int main(int argc, char **argv)
 
        tid_enqueuer = malloc(sizeof(*tid_enqueuer) * nr_enqueuers);
        tid_dequeuer = malloc(sizeof(*tid_dequeuer) * nr_dequeuers);
-       count_enqueuer = malloc(2 * sizeof(*count_enqueuer) * nr_enqueuers);
-       count_dequeuer = malloc(2 * sizeof(*count_dequeuer) * nr_dequeuers);
+       count_enqueuer = malloc(3 * sizeof(*count_enqueuer) * nr_enqueuers);
+       count_dequeuer = malloc(3 * sizeof(*count_dequeuer) * nr_dequeuers);
        cds_wfs_init(&s);
 
        next_aff = 0;
 
        for (i = 0; i < nr_enqueuers; i++) {
                err = pthread_create(&tid_enqueuer[i], NULL, thr_enqueuer,
-                                    &count_enqueuer[2 * i]);
+                                    &count_enqueuer[3 * i]);
                if (err != 0)
                        exit(1);
        }
        for (i = 0; i < nr_dequeuers; i++) {
                err = pthread_create(&tid_dequeuer[i], NULL, thr_dequeuer,
-                                    &count_dequeuer[2 * i]);
+                                    &count_dequeuer[3 * i]);
                if (err != 0)
                        exit(1);
        }
@@ -471,21 +499,34 @@ int main(int argc, char **argv)
                        write (1, ".", 1);
        }
 
-       test_stop = 1;
+       test_stop_enqueue = 1;
+
+       if (test_wait_empty) {
+               while (nr_enqueuers != uatomic_read(&test_enqueue_stopped)) {
+                       sleep(1);
+               }
+               while (!cds_wfs_empty(&s)) {
+                       sleep(1);
+               }
+       }
+
+       test_stop_dequeue = 1;
 
        for (i = 0; i < nr_enqueuers; i++) {
                err = pthread_join(tid_enqueuer[i], &tret);
                if (err != 0)
                        exit(1);
-               tot_enqueues += count_enqueuer[2 * i];
-               tot_successful_enqueues += count_enqueuer[2 * i + 1];
+               tot_enqueues += count_enqueuer[3 * i];
+               tot_successful_enqueues += count_enqueuer[3 * i + 1];
+               tot_empty_dest_enqueues += count_enqueuer[3 * i + 2];
        }
        for (i = 0; i < nr_dequeuers; i++) {
                err = pthread_join(tid_dequeuer[i], &tret);
                if (err != 0)
                        exit(1);
-               tot_dequeues += count_dequeuer[2 * i];
-               tot_successful_dequeues += count_dequeuer[2 * i + 1];
+               tot_dequeues += count_dequeuer[3 * i];
+               tot_successful_dequeues += count_dequeuer[3 * i + 1];
+               tot_pop_all += count_dequeuer[3 * i + 2];
        }
        
        test_end(&s, &end_dequeues);
@@ -493,27 +534,48 @@ int main(int argc, char **argv)
        printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
                       tot_enqueues, tot_dequeues);
        printf_verbose("total number of successful enqueues : %llu, "
-                      "successful dequeues %llu\n",
-                      tot_successful_enqueues, tot_successful_dequeues);
+                      "enqueues to empty dest : %llu, "
+                      "successful dequeues %llu, "
+                      "pop_all : %llu\n",
+                      tot_successful_enqueues,
+                      tot_empty_dest_enqueues,
+                      tot_successful_dequeues,
+                      tot_pop_all);
        printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
                "nr_dequeuers %3u "
                "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
-               "successful enqueues %12llu successful dequeues %12llu "
+               "successful enqueues %12llu enqueues to empty dest %12llu "
+               "successful dequeues %12llu pop_all %12llu "
                "end_dequeues %llu nr_ops %12llu\n",
                argv[0], duration, nr_enqueuers, wdelay,
                nr_dequeuers, rduration, tot_enqueues, tot_dequeues,
                tot_successful_enqueues,
-               tot_successful_dequeues, end_dequeues,
+               tot_empty_dest_enqueues,
+               tot_successful_dequeues, tot_pop_all, end_dequeues,
                tot_enqueues + tot_dequeues);
-       if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues)
+       if (tot_successful_enqueues != tot_successful_dequeues + end_dequeues) {
                printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
                       "succ. dequeues + end dequeues %llu.\n",
                       tot_successful_enqueues,
                       tot_successful_dequeues + end_dequeues);
-
+               retval = 1;
+       }
+       /*
+        * If only using pop_all to dequeue, the enqueuer should see
+        * exactly as many empty queues than the number of non-empty
+        * stacks dequeued.
+        */
+       if (test_wait_empty && test_pop_all && !test_pop
+                       && tot_empty_dest_enqueues != tot_pop_all) {
+               printf("WARNING! Discrepancy between empty enqueue (%llu) and "
+                       "number of non-empty pop_all (%llu)\n",
+                       tot_empty_dest_enqueues,
+                       tot_pop_all);
+               retval = 1;
+       }
        free(count_enqueuer);
        free(count_dequeuer);
        free(tid_enqueuer);
        free(tid_dequeuer);
-       return 0;
+       return retval;
 }