--- /dev/null
+/*
+ * rcuq_test.c
+ *
+ * usage: rcuq_test <readers> <duration>
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (c) 2013 Mike D. Day, IBM Corporation.
+ */
+
+#include <glib.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "qemu/atomic.h"
+#include "qemu/rcu.h"
+#include "qemu/compiler.h"
+#include "qemu/osdep.h"
+#include "qemu/thread.h"
+#include "qemu/rcu_queue.h"
+
+/*
+ * Test variables.
+ */
+
+static QemuMutex counts_mutex;
+static long long n_reads = 0LL;
+static long long n_updates = 0LL;
+static long long n_reclaims = 0LL;
+static long long n_nodes_removed = 0LL;
+static long long n_nodes = 0LL;
+static int g_test_in_charge = 0;
+
+static int nthreadsrunning;
+
+#define GOFLAG_INIT 0
+#define GOFLAG_RUN 1
+#define GOFLAG_STOP 2
+
+static volatile int goflag = GOFLAG_INIT;
+
+#define RCU_READ_RUN 1000
+#define RCU_UPDATE_RUN 10
+#define NR_THREADS 100
+#define RCU_Q_LEN 100
+
+static QemuThread threads[NR_THREADS];
+static struct rcu_reader_data *data[NR_THREADS];
+static int n_threads;
+
+static int select_random_el(int max)
+{
+ return (rand() % max);
+}
+
+
+static void create_thread(void *(*func)(void *))
+{
+ if (n_threads >= NR_THREADS) {
+ fprintf(stderr, "Thread limit of %d exceeded!\n", NR_THREADS);
+ exit(-1);
+ }
+ qemu_thread_create(&threads[n_threads], "test", func, &data[n_threads],
+ QEMU_THREAD_JOINABLE);
+ n_threads++;
+}
+
+static void wait_all_threads(void)
+{
+ int i;
+
+ for (i = 0; i < n_threads; i++) {
+ qemu_thread_join(&threads[i]);
+ }
+ n_threads = 0;
+}
+
+
+struct list_element {
+ QLIST_ENTRY(list_element) entry;
+ struct rcu_head rcu;
+};
+
+static void reclaim_list_el(struct rcu_head *prcu)
+{
+ struct list_element *el = container_of(prcu, struct list_element, rcu);
+ g_free(el);
+ /* Accessed only from call_rcu thread. */
+ n_reclaims++;
+}
+
+static QLIST_HEAD(q_list_head, list_element) Q_list_head;
+
+static void *rcu_q_reader(void *arg)
+{
+ long long n_reads_local = 0;
+ struct list_element *el;
+
+ rcu_register_thread();
+
+ *(struct rcu_reader_data **)arg = &rcu_reader;
+ atomic_inc(&nthreadsrunning);
+ while (goflag == GOFLAG_INIT) {
+ g_usleep(1000);
+ }
+
+ while (goflag == GOFLAG_RUN) {
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(el, &Q_list_head, entry) {
+ n_reads_local++;
+ if (goflag == GOFLAG_STOP) {
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ g_usleep(100);
+ }
+ qemu_mutex_lock(&counts_mutex);
+ n_reads += n_reads_local;
+ qemu_mutex_unlock(&counts_mutex);
+
+ rcu_unregister_thread();
+ return NULL;
+}
+
+
+static void *rcu_q_updater(void *arg)
+{
+ int j, target_el;
+ long long n_nodes_local = 0;
+ long long n_updates_local = 0;
+ long long n_removed_local = 0;
+ struct list_element *el, *prev_el;
+
+ *(struct rcu_reader_data **)arg = &rcu_reader;
+ atomic_inc(&nthreadsrunning);
+ while (goflag == GOFLAG_INIT) {
+ g_usleep(1000);
+ }
+
+ while (goflag == GOFLAG_RUN) {
+ target_el = select_random_el(RCU_Q_LEN);
+ j = 0;
+ /* FOREACH_RCU could work here but let's use both macros */
+ QLIST_FOREACH_SAFE_RCU(prev_el, &Q_list_head, entry, el) {
+ j++;
+ if (target_el == j) {
+ QLIST_REMOVE_RCU(prev_el, entry);
+ /* may be more than one updater in the future */
+ call_rcu1(&prev_el->rcu, reclaim_list_el);
+ n_removed_local++;
+ break;
+ }
+ }
+ if (goflag == GOFLAG_STOP) {
+ break;
+ }
+ target_el = select_random_el(RCU_Q_LEN);
+ j = 0;
+ QLIST_FOREACH_RCU(el, &Q_list_head, entry) {
+ j++;
+ if (target_el == j) {
+ prev_el = g_new(struct list_element, 1);
+ n_nodes += n_nodes_local;
+ QLIST_INSERT_BEFORE_RCU(el, prev_el, entry);
+ break;
+ }
+ }
+
+ n_updates_local += 2;
+ synchronize_rcu();
+ }
+ synchronize_rcu();
+ qemu_mutex_lock(&counts_mutex);
+ n_nodes += n_nodes_local;
+ n_updates += n_updates_local;
+ n_nodes_removed += n_removed_local;
+ qemu_mutex_unlock(&counts_mutex);
+ return NULL;
+}
+
+static void rcu_qtest_init(void)
+{
+ struct list_element *new_el;
+ int i;
+ nthreadsrunning = 0;
+ srand(time(0));
+ for (i = 0; i < RCU_Q_LEN; i++) {
+ new_el = g_new(struct list_element, 1);
+ QLIST_INSERT_HEAD_RCU(&Q_list_head, new_el, entry);
+ }
+ qemu_mutex_lock(&counts_mutex);
+ n_nodes += RCU_Q_LEN;
+ qemu_mutex_unlock(&counts_mutex);
+}
+
+static void rcu_qtest_run(int duration, int nreaders)
+{
+ int nthreads = nreaders + 1;
+ while (atomic_read(&nthreadsrunning) < nthreads) {
+ g_usleep(1000);
+ }
+
+ goflag = GOFLAG_RUN;
+ sleep(duration);
+ goflag = GOFLAG_STOP;
+ wait_all_threads();
+}
+
+
+static void rcu_qtest(const char *test, int duration, int nreaders)
+{
+ int i;
+ long long n_removed_local = 0;
+
+ struct list_element *el, *prev_el;
+
+ rcu_qtest_init();
+ for (i = 0; i < nreaders; i++) {
+ create_thread(rcu_q_reader);
+ }
+ create_thread(rcu_q_updater);
+ rcu_qtest_run(duration, nreaders);
+
+ QLIST_FOREACH_SAFE_RCU(prev_el, &Q_list_head, entry, el) {
+ QLIST_REMOVE_RCU(prev_el, entry);
+ call_rcu1(&prev_el->rcu, reclaim_list_el);
+ n_removed_local++;
+ }
+ qemu_mutex_lock(&counts_mutex);
+ n_nodes_removed += n_removed_local;
+ qemu_mutex_unlock(&counts_mutex);
+ synchronize_rcu();
+ while (n_nodes_removed > n_reclaims) {
+ g_usleep(100);
+ synchronize_rcu();
+ }
+ if (g_test_in_charge) {
+ g_assert_cmpint(n_nodes_removed, ==, n_reclaims);
+ } else {
+ printf("%s: %d readers; 1 updater; nodes read: " \
+ "%lld, nodes removed: %lld; nodes reclaimed: %lld\n",
+ test, nthreadsrunning - 1, n_reads, n_nodes_removed, n_reclaims);
+ exit(0);
+ }
+}
+
+static void usage(int argc, char *argv[])
+{
+ fprintf(stderr, "Usage: %s duration nreaders\n", argv[0]);
+ exit(-1);
+}
+
+static int gtest_seconds;
+
+static void gtest_rcuq_one(void)
+{
+ rcu_qtest("rcuqtest", gtest_seconds / 4, 1);
+}
+
+static void gtest_rcuq_few(void)
+{
+ rcu_qtest("rcuqtest", gtest_seconds / 4, 5);
+}
+
+static void gtest_rcuq_many(void)
+{
+ rcu_qtest("rcuqtest", gtest_seconds / 2, 20);
+}
+
+
+int main(int argc, char *argv[])
+{
+ int duration = 0, readers = 0;
+
+ qemu_mutex_init(&counts_mutex);
+ if (argc >= 2) {
+ if (argv[1][0] == '-') {
+ g_test_init(&argc, &argv, NULL);
+ if (g_test_quick()) {
+ gtest_seconds = 4;
+ } else {
+ gtest_seconds = 20;
+ }
+ g_test_add_func("/rcu/qlist/single-threaded", gtest_rcuq_one);
+ g_test_add_func("/rcu/qlist/short-few", gtest_rcuq_few);
+ g_test_add_func("/rcu/qlist/long-many", gtest_rcuq_many);
+ g_test_in_charge = 1;
+ return g_test_run();
+ }
+ duration = strtoul(argv[1], NULL, 0);
+ }
+ if (argc >= 3) {
+ readers = strtoul(argv[2], NULL, 0);
+ }
+ if (duration && readers) {
+ rcu_qtest(argv[0], duration, readers);
+ return 0;
+ }
+
+ usage(argc, argv);
+ return -1;
+}
Code Review / kvmfornfv.git / blobdiff