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