tests/test-coroutine.c

   1 /*
   2  * Coroutine tests
   3  *
   4  * Copyright IBM, Corp. 2011
   5  *
   6  * Authors:
   7  *  Stefan Hajnoczi    <stefanha@linux.vnet.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU LGPL, version 2 or later.
  10  * See the COPYING.LIB file in the top-level directory.
  11  *
  12  */
  13
  14 #include "qemu/osdep.h"
  15 #include "qemu/coroutine.h"
  16 #include "qemu/coroutine_int.h"
  17
  18 /*
  19  * Check that qemu_in_coroutine() works
  20  */
  21
  22 static void coroutine_fn verify_in_coroutine(void *opaque)
  23 {
  24     g_assert(qemu_in_coroutine());
  25 }
  26
  27 static void test_in_coroutine(void)
  28 {
  29     Coroutine *coroutine;
  30
  31     g_assert(!qemu_in_coroutine());
  32
  33     coroutine = qemu_coroutine_create(verify_in_coroutine, NULL);
  34     qemu_coroutine_enter(coroutine);
  35 }
  36
  37 /*
  38  * Check that qemu_coroutine_self() works
  39  */
  40
  41 static void coroutine_fn verify_self(void *opaque)
  42 {
  43     Coroutine **p_co = opaque;
  44     g_assert(qemu_coroutine_self() == *p_co);
  45 }
  46
  47 static void test_self(void)
  48 {
  49     Coroutine *coroutine;
  50
  51     coroutine = qemu_coroutine_create(verify_self, &coroutine);
  52     qemu_coroutine_enter(coroutine);
  53 }
  54
  55 /*
  56  * Check that qemu_coroutine_entered() works
  57  */
  58
  59 static void coroutine_fn verify_entered_step_2(void *opaque)
  60 {
  61     Coroutine *caller = (Coroutine *)opaque;
  62
  63     g_assert(qemu_coroutine_entered(caller));
  64     g_assert(qemu_coroutine_entered(qemu_coroutine_self()));
  65     qemu_coroutine_yield();
  66
  67     /* Once more to check it still works after yielding */
  68     g_assert(qemu_coroutine_entered(caller));
  69     g_assert(qemu_coroutine_entered(qemu_coroutine_self()));
  70     qemu_coroutine_yield();
  71 }
  72
  73 static void coroutine_fn verify_entered_step_1(void *opaque)
  74 {
  75     Coroutine *self = qemu_coroutine_self();
  76     Coroutine *coroutine;
  77
  78     g_assert(qemu_coroutine_entered(self));
  79
  80     coroutine = qemu_coroutine_create(verify_entered_step_2, self);
  81     g_assert(!qemu_coroutine_entered(coroutine));
  82     qemu_coroutine_enter(coroutine);
  83     g_assert(!qemu_coroutine_entered(coroutine));
  84     qemu_coroutine_enter(coroutine);
  85 }
  86
  87 static void test_entered(void)
  88 {
  89     Coroutine *coroutine;
  90
  91     coroutine = qemu_coroutine_create(verify_entered_step_1, NULL);
  92     g_assert(!qemu_coroutine_entered(coroutine));
  93     qemu_coroutine_enter(coroutine);
  94 }
  95
  96 /*
  97  * Check that coroutines may nest multiple levels
  98  */
  99
 100 typedef struct {
 101     unsigned int n_enter;   /* num coroutines entered */
 102     unsigned int n_return;  /* num coroutines returned */
 103     unsigned int max;       /* maximum level of nesting */
 104 } NestData;
 105
 106 static void coroutine_fn nest(void *opaque)
 107 {
 108     NestData *nd = opaque;
 109
 110     nd->n_enter++;
 111
 112     if (nd->n_enter < nd->max) {
 113         Coroutine *child;
 114
 115         child = qemu_coroutine_create(nest, nd);
 116         qemu_coroutine_enter(child);
 117     }
 118
 119     nd->n_return++;
 120 }
 121
 122 static void test_nesting(void)
 123 {
 124     Coroutine *root;
 125     NestData nd = {
 126         .n_enter  = 0,
 127         .n_return = 0,
 128         .max      = 128,
 129     };
 130
 131     root = qemu_coroutine_create(nest, &nd);
 132     qemu_coroutine_enter(root);
 133
 134     /* Must enter and return from max nesting level */
 135     g_assert_cmpint(nd.n_enter, ==, nd.max);
 136     g_assert_cmpint(nd.n_return, ==, nd.max);
 137 }
 138
 139 /*
 140  * Check that yield/enter transfer control correctly
 141  */
 142
 143 static void coroutine_fn yield_5_times(void *opaque)
 144 {
 145     bool *done = opaque;
 146     int i;
 147
 148     for (i = 0; i < 5; i++) {
 149         qemu_coroutine_yield();
 150     }
 151     *done = true;
 152 }
 153
 154 static void test_yield(void)
 155 {
 156     Coroutine *coroutine;
 157     bool done = false;
 158     int i = -1; /* one extra time to return from coroutine */
 159
 160     coroutine = qemu_coroutine_create(yield_5_times, &done);
 161     while (!done) {
 162         qemu_coroutine_enter(coroutine);
 163         i++;
 164     }
 165     g_assert_cmpint(i, ==, 5); /* coroutine must yield 5 times */
 166 }
 167
 168 static void coroutine_fn c2_fn(void *opaque)
 169 {
 170     qemu_coroutine_yield();
 171 }
 172
 173 static void coroutine_fn c1_fn(void *opaque)
 174 {
 175     Coroutine *c2 = opaque;
 176     qemu_coroutine_enter(c2);
 177 }
 178
 179 static void test_co_queue(void)
 180 {
 181     Coroutine *c1;
 182     Coroutine *c2;
 183     Coroutine tmp;
 184
 185     c2 = qemu_coroutine_create(c2_fn, NULL);
 186     c1 = qemu_coroutine_create(c1_fn, c2);
 187
 188     qemu_coroutine_enter(c1);
 189
 190     /* c1 shouldn't be used any more now; make sure we segfault if it is */
 191     tmp = *c1;
 192     memset(c1, 0xff, sizeof(Coroutine));
 193     qemu_coroutine_enter(c2);
 194
 195     /* Must restore the coroutine now to avoid corrupted pool */
 196     *c1 = tmp;
 197 }
 198
 199 /*
 200  * Check that creation, enter, and return work
 201  */
 202
 203 static void coroutine_fn set_and_exit(void *opaque)
 204 {
 205     bool *done = opaque;
 206
 207     *done = true;
 208 }
 209
 210 static void test_lifecycle(void)
 211 {
 212     Coroutine *coroutine;
 213     bool done = false;
 214
 215     /* Create, enter, and return from coroutine */
 216     coroutine = qemu_coroutine_create(set_and_exit, &done);
 217     qemu_coroutine_enter(coroutine);
 218     g_assert(done); /* expect done to be true (first time) */
 219
 220     /* Repeat to check that no state affects this test */
 221     done = false;
 222     coroutine = qemu_coroutine_create(set_and_exit, &done);
 223     qemu_coroutine_enter(coroutine);
 224     g_assert(done); /* expect done to be true (second time) */
 225 }
 226
 227
 228 #define RECORD_SIZE 10 /* Leave some room for expansion */
 229 struct coroutine_position {
 230     int func;
 231     int state;
 232 };
 233 static struct coroutine_position records[RECORD_SIZE];
 234 static unsigned record_pos;
 235
 236 static void record_push(int func, int state)
 237 {
 238     struct coroutine_position *cp = &records[record_pos++];
 239     g_assert_cmpint(record_pos, <, RECORD_SIZE);
 240     cp->func = func;
 241     cp->state = state;
 242 }
 243
 244 static void coroutine_fn co_order_test(void *opaque)
 245 {
 246     record_push(2, 1);
 247     g_assert(qemu_in_coroutine());
 248     qemu_coroutine_yield();
 249     record_push(2, 2);
 250     g_assert(qemu_in_coroutine());
 251 }
 252
 253 static void do_order_test(void)
 254 {
 255     Coroutine *co;
 256
 257     co = qemu_coroutine_create(co_order_test, NULL);
 258     record_push(1, 1);
 259     qemu_coroutine_enter(co);
 260     record_push(1, 2);
 261     g_assert(!qemu_in_coroutine());
 262     qemu_coroutine_enter(co);
 263     record_push(1, 3);
 264     g_assert(!qemu_in_coroutine());
 265 }
 266
 267 static void test_order(void)
 268 {
 269     int i;
 270     const struct coroutine_position expected_pos[] = {
 271         {1, 1,}, {2, 1}, {1, 2}, {2, 2}, {1, 3}
 272     };
 273     do_order_test();
 274     g_assert_cmpint(record_pos, ==, 5);
 275     for (i = 0; i < record_pos; i++) {
 276         g_assert_cmpint(records[i].func , ==, expected_pos[i].func );
 277         g_assert_cmpint(records[i].state, ==, expected_pos[i].state);
 278     }
 279 }
 280 /*
 281  * Lifecycle benchmark
 282  */
 283
 284 static void coroutine_fn empty_coroutine(void *opaque)
 285 {
 286     /* Do nothing */
 287 }
 288
 289 static void perf_lifecycle(void)
 290 {
 291     Coroutine *coroutine;
 292     unsigned int i, max;
 293     double duration;
 294
 295     max = 1000000;
 296
 297     g_test_timer_start();
 298     for (i = 0; i < max; i++) {
 299         coroutine = qemu_coroutine_create(empty_coroutine, NULL);
 300         qemu_coroutine_enter(coroutine);
 301     }
 302     duration = g_test_timer_elapsed();
 303
 304     g_test_message("Lifecycle %u iterations: %f s\n", max, duration);
 305 }
 306
 307 static void perf_nesting(void)
 308 {
 309     unsigned int i, maxcycles, maxnesting;
 310     double duration;
 311
 312     maxcycles = 10000;
 313     maxnesting = 1000;
 314     Coroutine *root;
 315
 316     g_test_timer_start();
 317     for (i = 0; i < maxcycles; i++) {
 318         NestData nd = {
 319             .n_enter  = 0,
 320             .n_return = 0,
 321             .max      = maxnesting,
 322         };
 323         root = qemu_coroutine_create(nest, &nd);
 324         qemu_coroutine_enter(root);
 325     }
 326     duration = g_test_timer_elapsed();
 327
 328     g_test_message("Nesting %u iterations of %u depth each: %f s\n",
 329         maxcycles, maxnesting, duration);
 330 }
 331
 332 /*
 333  * Yield benchmark
 334  */
 335
 336 static void coroutine_fn yield_loop(void *opaque)
 337 {
 338     unsigned int *counter = opaque;
 339
 340     while ((*counter) > 0) {
 341         (*counter)--;
 342         qemu_coroutine_yield();
 343     }
 344 }
 345
 346 static void perf_yield(void)
 347 {
 348     unsigned int i, maxcycles;
 349     double duration;
 350
 351     maxcycles = 100000000;
 352     i = maxcycles;
 353     Coroutine *coroutine = qemu_coroutine_create(yield_loop, &i);
 354
 355     g_test_timer_start();
 356     while (i > 0) {
 357         qemu_coroutine_enter(coroutine);
 358     }
 359     duration = g_test_timer_elapsed();
 360
 361     g_test_message("Yield %u iterations: %f s\n",
 362         maxcycles, duration);
 363 }
 364
 365 static __attribute__((noinline)) void dummy(unsigned *i)
 366 {
 367     (*i)--;
 368 }
 369
 370 static void perf_baseline(void)
 371 {
 372     unsigned int i, maxcycles;
 373     double duration;
 374
 375     maxcycles = 100000000;
 376     i = maxcycles;
 377
 378     g_test_timer_start();
 379     while (i > 0) {
 380         dummy(&i);
 381     }
 382     duration = g_test_timer_elapsed();
 383
 384     g_test_message("Function call %u iterations: %f s\n",
 385         maxcycles, duration);
 386 }
 387
 388 static __attribute__((noinline)) void perf_cost_func(void *opaque)
 389 {
 390     qemu_coroutine_yield();
 391 }
 392
 393 static void perf_cost(void)
 394 {
 395     const unsigned long maxcycles = 40000000;
 396     unsigned long i = 0;
 397     double duration;
 398     unsigned long ops;
 399     Coroutine *co;
 400
 401     g_test_timer_start();
 402     while (i++ < maxcycles) {
 403         co = qemu_coroutine_create(perf_cost_func, &i);
 404         qemu_coroutine_enter(co);
 405         qemu_coroutine_enter(co);
 406     }
 407     duration = g_test_timer_elapsed();
 408     ops = (long)(maxcycles / (duration * 1000));
 409
 410     g_test_message("Run operation %lu iterations %f s, %luK operations/s, "
 411                    "%luns per coroutine",
 412                    maxcycles,
 413                    duration, ops,
 414                    (unsigned long)(1000000000.0 * duration / maxcycles));
 415 }
 416
 417 int main(int argc, char **argv)
 418 {
 419     g_test_init(&argc, &argv, NULL);
 420
 421     /* This test assumes there is a freelist and marks freed coroutine memory
 422      * with a sentinel value.  If there is no freelist this would legitimately
 423      * crash, so skip it.
 424      */
 425     if (CONFIG_COROUTINE_POOL) {
 426         g_test_add_func("/basic/co_queue", test_co_queue);
 427     }
 428
 429     g_test_add_func("/basic/lifecycle", test_lifecycle);
 430     g_test_add_func("/basic/yield", test_yield);
 431     g_test_add_func("/basic/nesting", test_nesting);
 432     g_test_add_func("/basic/self", test_self);
 433     g_test_add_func("/basic/entered", test_entered);
 434     g_test_add_func("/basic/in_coroutine", test_in_coroutine);
 435     g_test_add_func("/basic/order", test_order);
 436     if (g_test_perf()) {
 437         g_test_add_func("/perf/lifecycle", perf_lifecycle);
 438         g_test_add_func("/perf/nesting", perf_nesting);
 439         g_test_add_func("/perf/yield", perf_yield);
 440         g_test_add_func("/perf/function-call", perf_baseline);
 441         g_test_add_func("/perf/cost", perf_cost);
 442     }
 443     return g_test_run();
 444 }