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23#include "qemu/osdep.h"
24#include "qemu/atomic.h"
25#include "qemu/rcu.h"
26#include "qemu/thread.h"
27#include "qemu/rcu_queue.h"
28
29
30
31
32
33static QemuMutex counts_mutex;
34static long long n_reads = 0LL;
35static long long n_updates = 0LL;
36static int64_t n_reclaims;
37static int64_t n_nodes_removed;
38static long long n_nodes = 0LL;
39static int g_test_in_charge = 0;
40
41static int nthreadsrunning;
42
43#define GOFLAG_INIT 0
44#define GOFLAG_RUN 1
45#define GOFLAG_STOP 2
46
47static int goflag = GOFLAG_INIT;
48
49#define RCU_READ_RUN 1000
50#define RCU_UPDATE_RUN 10
51#define NR_THREADS 100
52#define RCU_Q_LEN 100
53
54static QemuThread threads[NR_THREADS];
55static struct rcu_reader_data *data[NR_THREADS];
56static int n_threads;
57
58static int select_random_el(int max)
59{
60 return (rand() % max);
61}
62
63
64static void create_thread(void *(*func)(void *))
65{
66 if (n_threads >= NR_THREADS) {
67 fprintf(stderr, "Thread limit of %d exceeded!\n", NR_THREADS);
68 exit(-1);
69 }
70 qemu_thread_create(&threads[n_threads], "test", func, &data[n_threads],
71 QEMU_THREAD_JOINABLE);
72 n_threads++;
73}
74
75static void wait_all_threads(void)
76{
77 int i;
78
79 for (i = 0; i < n_threads; i++) {
80 qemu_thread_join(&threads[i]);
81 }
82 n_threads = 0;
83}
84
85#ifndef TEST_LIST_TYPE
86#define TEST_LIST_TYPE 1
87#endif
88
89struct list_element {
90#if TEST_LIST_TYPE == 1
91 QLIST_ENTRY(list_element) entry;
92#elif TEST_LIST_TYPE == 2
93 QSIMPLEQ_ENTRY(list_element) entry;
94#elif TEST_LIST_TYPE == 3
95 QTAILQ_ENTRY(list_element) entry;
96#elif TEST_LIST_TYPE == 4
97 QSLIST_ENTRY(list_element) entry;
98#else
99#error Invalid TEST_LIST_TYPE
100#endif
101 struct rcu_head rcu;
102};
103
104static void reclaim_list_el(struct rcu_head *prcu)
105{
106 struct list_element *el = container_of(prcu, struct list_element, rcu);
107 g_free(el);
108
109 qatomic_set_i64(&n_reclaims, n_reclaims + 1);
110}
111
112#if TEST_LIST_TYPE == 1
113static QLIST_HEAD(, list_element) Q_list_head;
114
115#define TEST_NAME "qlist"
116#define TEST_LIST_REMOVE_RCU QLIST_REMOVE_RCU
117#define TEST_LIST_INSERT_AFTER_RCU QLIST_INSERT_AFTER_RCU
118#define TEST_LIST_INSERT_HEAD_RCU QLIST_INSERT_HEAD_RCU
119#define TEST_LIST_FOREACH_RCU QLIST_FOREACH_RCU
120#define TEST_LIST_FOREACH_SAFE_RCU QLIST_FOREACH_SAFE_RCU
121
122#elif TEST_LIST_TYPE == 2
123static QSIMPLEQ_HEAD(, list_element) Q_list_head =
124 QSIMPLEQ_HEAD_INITIALIZER(Q_list_head);
125
126#define TEST_NAME "qsimpleq"
127#define TEST_LIST_REMOVE_RCU(el, f) \
128 QSIMPLEQ_REMOVE_RCU(&Q_list_head, el, list_element, f)
129
130#define TEST_LIST_INSERT_AFTER_RCU(list_el, el, f) \
131 QSIMPLEQ_INSERT_AFTER_RCU(&Q_list_head, list_el, el, f)
132
133#define TEST_LIST_INSERT_HEAD_RCU QSIMPLEQ_INSERT_HEAD_RCU
134#define TEST_LIST_FOREACH_RCU QSIMPLEQ_FOREACH_RCU
135#define TEST_LIST_FOREACH_SAFE_RCU QSIMPLEQ_FOREACH_SAFE_RCU
136
137#elif TEST_LIST_TYPE == 3
138static QTAILQ_HEAD(, list_element) Q_list_head;
139
140#define TEST_NAME "qtailq"
141#define TEST_LIST_REMOVE_RCU(el, f) QTAILQ_REMOVE_RCU(&Q_list_head, el, f)
142
143#define TEST_LIST_INSERT_AFTER_RCU(list_el, el, f) \
144 QTAILQ_INSERT_AFTER_RCU(&Q_list_head, list_el, el, f)
145
146#define TEST_LIST_INSERT_HEAD_RCU QTAILQ_INSERT_HEAD_RCU
147#define TEST_LIST_FOREACH_RCU QTAILQ_FOREACH_RCU
148#define TEST_LIST_FOREACH_SAFE_RCU QTAILQ_FOREACH_SAFE_RCU
149
150#elif TEST_LIST_TYPE == 4
151static QSLIST_HEAD(, list_element) Q_list_head;
152
153#define TEST_NAME "qslist"
154#define TEST_LIST_REMOVE_RCU(el, f) \
155 QSLIST_REMOVE_RCU(&Q_list_head, el, list_element, f)
156
157#define TEST_LIST_INSERT_AFTER_RCU(list_el, el, f) \
158 QSLIST_INSERT_AFTER_RCU(&Q_list_head, list_el, el, f)
159
160#define TEST_LIST_INSERT_HEAD_RCU QSLIST_INSERT_HEAD_RCU
161#define TEST_LIST_FOREACH_RCU QSLIST_FOREACH_RCU
162#define TEST_LIST_FOREACH_SAFE_RCU QSLIST_FOREACH_SAFE_RCU
163#else
164#error Invalid TEST_LIST_TYPE
165#endif
166
167static void *rcu_q_reader(void *arg)
168{
169 long long n_reads_local = 0;
170 struct list_element *el;
171
172 rcu_register_thread();
173
174 *(struct rcu_reader_data **)arg = &rcu_reader;
175 qatomic_inc(&nthreadsrunning);
176 while (qatomic_read(&goflag) == GOFLAG_INIT) {
177 g_usleep(1000);
178 }
179
180 while (qatomic_read(&goflag) == GOFLAG_RUN) {
181 rcu_read_lock();
182 TEST_LIST_FOREACH_RCU(el, &Q_list_head, entry) {
183 n_reads_local++;
184 if (qatomic_read(&goflag) == GOFLAG_STOP) {
185 break;
186 }
187 }
188 rcu_read_unlock();
189
190 g_usleep(100);
191 }
192 qemu_mutex_lock(&counts_mutex);
193 n_reads += n_reads_local;
194 qemu_mutex_unlock(&counts_mutex);
195
196 rcu_unregister_thread();
197 return NULL;
198}
199
200
201static void *rcu_q_updater(void *arg)
202{
203 int j, target_el;
204 long long n_nodes_local = 0;
205 long long n_updates_local = 0;
206 long long n_removed_local = 0;
207 struct list_element *el, *prev_el;
208
209 *(struct rcu_reader_data **)arg = &rcu_reader;
210 qatomic_inc(&nthreadsrunning);
211 while (qatomic_read(&goflag) == GOFLAG_INIT) {
212 g_usleep(1000);
213 }
214
215 while (qatomic_read(&goflag) == GOFLAG_RUN) {
216 target_el = select_random_el(RCU_Q_LEN);
217 j = 0;
218
219 TEST_LIST_FOREACH_SAFE_RCU(prev_el, &Q_list_head, entry, el) {
220 j++;
221 if (target_el == j) {
222 TEST_LIST_REMOVE_RCU(prev_el, entry);
223
224 call_rcu1(&prev_el->rcu, reclaim_list_el);
225 n_removed_local++;
226 break;
227 }
228 }
229 if (qatomic_read(&goflag) == GOFLAG_STOP) {
230 break;
231 }
232 target_el = select_random_el(RCU_Q_LEN);
233 j = 0;
234 TEST_LIST_FOREACH_RCU(el, &Q_list_head, entry) {
235 j++;
236 if (target_el == j) {
237 struct list_element *new_el = g_new(struct list_element, 1);
238 n_nodes_local++;
239 TEST_LIST_INSERT_AFTER_RCU(el, new_el, entry);
240 break;
241 }
242 }
243
244 n_updates_local += 2;
245 synchronize_rcu();
246 }
247 synchronize_rcu();
248 qemu_mutex_lock(&counts_mutex);
249 n_nodes += n_nodes_local;
250 n_updates += n_updates_local;
251 qatomic_set_i64(&n_nodes_removed, n_nodes_removed + n_removed_local);
252 qemu_mutex_unlock(&counts_mutex);
253 return NULL;
254}
255
256static void rcu_qtest_init(void)
257{
258 struct list_element *new_el;
259 int i;
260 nthreadsrunning = 0;
261 srand(time(0));
262 for (i = 0; i < RCU_Q_LEN; i++) {
263 new_el = g_new(struct list_element, 1);
264 TEST_LIST_INSERT_HEAD_RCU(&Q_list_head, new_el, entry);
265 }
266 qemu_mutex_lock(&counts_mutex);
267 n_nodes += RCU_Q_LEN;
268 qemu_mutex_unlock(&counts_mutex);
269}
270
271static void rcu_qtest_run(int duration, int nreaders)
272{
273 int nthreads = nreaders + 1;
274 while (qatomic_read(&nthreadsrunning) < nthreads) {
275 g_usleep(1000);
276 }
277
278 qatomic_set(&goflag, GOFLAG_RUN);
279 sleep(duration);
280 qatomic_set(&goflag, GOFLAG_STOP);
281 wait_all_threads();
282}
283
284
285static void rcu_qtest(const char *test, int duration, int nreaders)
286{
287 int i;
288 long long n_removed_local = 0;
289
290 struct list_element *el, *prev_el;
291
292 rcu_qtest_init();
293 for (i = 0; i < nreaders; i++) {
294 create_thread(rcu_q_reader);
295 }
296 create_thread(rcu_q_updater);
297 rcu_qtest_run(duration, nreaders);
298
299 TEST_LIST_FOREACH_SAFE_RCU(prev_el, &Q_list_head, entry, el) {
300 TEST_LIST_REMOVE_RCU(prev_el, entry);
301 call_rcu1(&prev_el->rcu, reclaim_list_el);
302 n_removed_local++;
303 }
304 qemu_mutex_lock(&counts_mutex);
305 qatomic_set_i64(&n_nodes_removed, n_nodes_removed + n_removed_local);
306 qemu_mutex_unlock(&counts_mutex);
307 synchronize_rcu();
308 while (qatomic_read_i64(&n_nodes_removed) >
309 qatomic_read_i64(&n_reclaims)) {
310 g_usleep(100);
311 synchronize_rcu();
312 }
313 if (g_test_in_charge) {
314 g_assert_cmpint(qatomic_read_i64(&n_nodes_removed), ==,
315 qatomic_read_i64(&n_reclaims));
316 } else {
317 printf("%s: %d readers; 1 updater; nodes read: " \
318 "%lld, nodes removed: %"PRIi64"; nodes reclaimed: %"PRIi64"\n",
319 test, nthreadsrunning - 1, n_reads,
320 qatomic_read_i64(&n_nodes_removed),
321 qatomic_read_i64(&n_reclaims));
322 exit(0);
323 }
324}
325
326static void usage(int argc, char *argv[])
327{
328 fprintf(stderr, "Usage: %s duration nreaders\n", argv[0]);
329 exit(-1);
330}
331
332static int gtest_seconds;
333
334static void gtest_rcuq_one(void)
335{
336 rcu_qtest("rcuqtest", gtest_seconds / 4, 1);
337}
338
339static void gtest_rcuq_few(void)
340{
341 rcu_qtest("rcuqtest", gtest_seconds / 4, 5);
342}
343
344static void gtest_rcuq_many(void)
345{
346 rcu_qtest("rcuqtest", gtest_seconds / 2, 20);
347}
348
349
350int main(int argc, char *argv[])
351{
352 int duration = 0, readers = 0;
353
354 qemu_mutex_init(&counts_mutex);
355 if (argc >= 2) {
356 if (argv[1][0] == '-') {
357 g_test_init(&argc, &argv, NULL);
358 if (g_test_quick()) {
359 gtest_seconds = 4;
360 } else {
361 gtest_seconds = 20;
362 }
363 g_test_add_func("/rcu/"TEST_NAME"/single-threaded", gtest_rcuq_one);
364 g_test_add_func("/rcu/"TEST_NAME"/short-few", gtest_rcuq_few);
365 g_test_add_func("/rcu/"TEST_NAME"/long-many", gtest_rcuq_many);
366 g_test_in_charge = 1;
367 return g_test_run();
368 }
369 duration = strtoul(argv[1], NULL, 0);
370 }
371 if (argc >= 3) {
372 readers = strtoul(argv[2], NULL, 0);
373 }
374 if (duration && readers) {
375 rcu_qtest(argv[0], duration, readers);
376 return 0;
377 }
378
379 usage(argc, argv);
380 return -1;
381}
382
