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 <glib.h>
  15 #include "block/coroutine.h"
  16
  17 /*
  18  * Check that qemu_in_coroutine() works
  19  */
  20
  21 static void coroutine_fn verify_in_coroutine(void *opaque)
  22 {
  23     g_assert(qemu_in_coroutine());
  24 }
  25
  26 static void test_in_coroutine(void)
  27 {
  28     Coroutine *coroutine;
  29
  30     g_assert(!qemu_in_coroutine());
  31
  32     coroutine = qemu_coroutine_create(verify_in_coroutine);
  33     qemu_coroutine_enter(coroutine, NULL);
  34 }
  35
  36 /*
  37  * Check that qemu_coroutine_self() works
  38  */
  39
  40 static void coroutine_fn verify_self(void *opaque)
  41 {
  42     g_assert(qemu_coroutine_self() == opaque);
  43 }
  44
  45 static void test_self(void)
  46 {
  47     Coroutine *coroutine;
  48
  49     coroutine = qemu_coroutine_create(verify_self);
  50     qemu_coroutine_enter(coroutine, coroutine);
  51 }
  52
  53 /*
  54  * Check that coroutines may nest multiple levels
  55  */
  56
  57 typedef struct {
  58     unsigned int n_enter;   /* num coroutines entered */
  59     unsigned int n_return;  /* num coroutines returned */
  60     unsigned int max;       /* maximum level of nesting */
  61 } NestData;
  62
  63 static void coroutine_fn nest(void *opaque)
  64 {
  65     NestData *nd = opaque;
  66
  67     nd->n_enter++;
  68
  69     if (nd->n_enter < nd->max) {
  70         Coroutine *child;
  71
  72         child = qemu_coroutine_create(nest);
  73         qemu_coroutine_enter(child, nd);
  74     }
  75
  76     nd->n_return++;
  77 }
  78
  79 static void test_nesting(void)
  80 {
  81     Coroutine *root;
  82     NestData nd = {
  83         .n_enter  = 0,
  84         .n_return = 0,
  85         .max      = 128,
  86     };
  87
  88     root = qemu_coroutine_create(nest);
  89     qemu_coroutine_enter(root, &nd);
  90
  91     /* Must enter and return from max nesting level */
  92     g_assert_cmpint(nd.n_enter, ==, nd.max);
  93     g_assert_cmpint(nd.n_return, ==, nd.max);
  94 }
  95
  96 /*
  97  * Check that yield/enter transfer control correctly
  98  */
  99
 100 static void coroutine_fn yield_5_times(void *opaque)
 101 {
 102     bool *done = opaque;
 103     int i;
 104
 105     for (i = 0; i < 5; i++) {
 106         qemu_coroutine_yield();
 107     }
 108     *done = true;
 109 }
 110
 111 static void test_yield(void)
 112 {
 113     Coroutine *coroutine;
 114     bool done = false;
 115     int i = -1; /* one extra time to return from coroutine */
 116
 117     coroutine = qemu_coroutine_create(yield_5_times);
 118     while (!done) {
 119         qemu_coroutine_enter(coroutine, &done);
 120         i++;
 121     }
 122     g_assert_cmpint(i, ==, 5); /* coroutine must yield 5 times */
 123 }
 124
 125 /*
 126  * Check that creation, enter, and return work
 127  */
 128
 129 static void coroutine_fn set_and_exit(void *opaque)
 130 {
 131     bool *done = opaque;
 132
 133     *done = true;
 134 }
 135
 136 static void test_lifecycle(void)
 137 {
 138     Coroutine *coroutine;
 139     bool done = false;
 140
 141     /* Create, enter, and return from coroutine */
 142     coroutine = qemu_coroutine_create(set_and_exit);
 143     qemu_coroutine_enter(coroutine, &done);
 144     g_assert(done); /* expect done to be true (first time) */
 145
 146     /* Repeat to check that no state affects this test */
 147     done = false;
 148     coroutine = qemu_coroutine_create(set_and_exit);
 149     qemu_coroutine_enter(coroutine, &done);
 150     g_assert(done); /* expect done to be true (second time) */
 151 }
 152
 153
 154 #define RECORD_SIZE 10 /* Leave some room for expansion */
 155 struct coroutine_position {
 156     int func;
 157     int state;
 158 };
 159 static struct coroutine_position records[RECORD_SIZE];
 160 static unsigned record_pos;
 161
 162 static void record_push(int func, int state)
 163 {
 164     struct coroutine_position *cp = &records[record_pos++];
 165     g_assert_cmpint(record_pos, <, RECORD_SIZE);
 166     cp->func = func;
 167     cp->state = state;
 168 }
 169
 170 static void coroutine_fn co_order_test(void *opaque)
 171 {
 172     record_push(2, 1);
 173     g_assert(qemu_in_coroutine());
 174     qemu_coroutine_yield();
 175     record_push(2, 2);
 176     g_assert(qemu_in_coroutine());
 177 }
 178
 179 static void do_order_test(void)
 180 {
 181     Coroutine *co;
 182
 183     co = qemu_coroutine_create(co_order_test);
 184     record_push(1, 1);
 185     qemu_coroutine_enter(co, NULL);
 186     record_push(1, 2);
 187     g_assert(!qemu_in_coroutine());
 188     qemu_coroutine_enter(co, NULL);
 189     record_push(1, 3);
 190     g_assert(!qemu_in_coroutine());
 191 }
 192
 193 static void test_order(void)
 194 {
 195     int i;
 196     const struct coroutine_position expected_pos[] = {
 197         {1, 1,}, {2, 1}, {1, 2}, {2, 2}, {1, 3}
 198     };
 199     do_order_test();
 200     g_assert_cmpint(record_pos, ==, 5);
 201     for (i = 0; i < record_pos; i++) {
 202         g_assert_cmpint(records[i].func , ==, expected_pos[i].func );
 203         g_assert_cmpint(records[i].state, ==, expected_pos[i].state);
 204     }
 205 }
 206 /*
 207  * Lifecycle benchmark
 208  */
 209
 210 static void coroutine_fn empty_coroutine(void *opaque)
 211 {
 212     /* Do nothing */
 213 }
 214
 215 static void perf_lifecycle(void)
 216 {
 217     Coroutine *coroutine;
 218     unsigned int i, max;
 219     double duration;
 220
 221     max = 1000000;
 222
 223     g_test_timer_start();
 224     for (i = 0; i < max; i++) {
 225         coroutine = qemu_coroutine_create(empty_coroutine);
 226         qemu_coroutine_enter(coroutine, NULL);
 227     }
 228     duration = g_test_timer_elapsed();
 229
 230     g_test_message("Lifecycle %u iterations: %f s\n", max, duration);
 231 }
 232
 233 static void perf_nesting(void)
 234 {
 235     unsigned int i, maxcycles, maxnesting;
 236     double duration;
 237
 238     maxcycles = 10000;
 239     maxnesting = 1000;
 240     Coroutine *root;
 241
 242     g_test_timer_start();
 243     for (i = 0; i < maxcycles; i++) {
 244         NestData nd = {
 245             .n_enter  = 0,
 246             .n_return = 0,
 247             .max      = maxnesting,
 248         };
 249         root = qemu_coroutine_create(nest);
 250         qemu_coroutine_enter(root, &nd);
 251     }
 252     duration = g_test_timer_elapsed();
 253
 254     g_test_message("Nesting %u iterations of %u depth each: %f s\n",
 255         maxcycles, maxnesting, duration);
 256 }
 257
 258 /*
 259  * Yield benchmark
 260  */
 261
 262 static void coroutine_fn yield_loop(void *opaque)
 263 {
 264     unsigned int *counter = opaque;
 265
 266     while ((*counter) > 0) {
 267         (*counter)--;
 268         qemu_coroutine_yield();
 269     }
 270 }
 271
 272 static void perf_yield(void)
 273 {
 274     unsigned int i, maxcycles;
 275     double duration;
 276
 277     maxcycles = 100000000;
 278     i = maxcycles;
 279     Coroutine *coroutine = qemu_coroutine_create(yield_loop);
 280
 281     g_test_timer_start();
 282     while (i > 0) {
 283         qemu_coroutine_enter(coroutine, &i);
 284     }
 285     duration = g_test_timer_elapsed();
 286
 287     g_test_message("Yield %u iterations: %f s\n",
 288         maxcycles, duration);
 289 }
 290
 291 static __attribute__((noinline)) void dummy(unsigned *i)
 292 {
 293     (*i)--;
 294 }
 295
 296 static void perf_baseline(void)
 297 {
 298     unsigned int i, maxcycles;
 299     double duration;
 300
 301     maxcycles = 100000000;
 302     i = maxcycles;
 303
 304     g_test_timer_start();
 305     while (i > 0) {
 306         dummy(&i);
 307     }
 308     duration = g_test_timer_elapsed();
 309
 310     g_test_message("Function call %u iterations: %f s\n",
 311         maxcycles, duration);
 312 }
 313
 314 static __attribute__((noinline)) void perf_cost_func(void *opaque)
 315 {
 316     qemu_coroutine_yield();
 317 }
 318
 319 static void perf_cost(void)
 320 {
 321     const unsigned long maxcycles = 40000000;
 322     unsigned long i = 0;
 323     double duration;
 324     unsigned long ops;
 325     Coroutine *co;
 326
 327     g_test_timer_start();
 328     while (i++ < maxcycles) {
 329         co = qemu_coroutine_create(perf_cost_func);
 330         qemu_coroutine_enter(co, &i);
 331         qemu_coroutine_enter(co, NULL);
 332     }
 333     duration = g_test_timer_elapsed();
 334     ops = (long)(maxcycles / (duration * 1000));
 335
 336     g_test_message("Run operation %lu iterations %f s, %luK operations/s, "
 337                    "%luns per coroutine",
 338                    maxcycles,
 339                    duration, ops,
 340                    (unsigned long)(1000000000 * duration) / maxcycles);
 341 }
 342
 343 int main(int argc, char **argv)
 344 {
 345     g_test_init(&argc, &argv, NULL);
 346     g_test_add_func("/basic/lifecycle", test_lifecycle);
 347     g_test_add_func("/basic/yield", test_yield);
 348     g_test_add_func("/basic/nesting", test_nesting);
 349     g_test_add_func("/basic/self", test_self);
 350     g_test_add_func("/basic/in_coroutine", test_in_coroutine);
 351     g_test_add_func("/basic/order", test_order);
 352     if (g_test_perf()) {
 353         g_test_add_func("/perf/lifecycle", perf_lifecycle);
 354         g_test_add_func("/perf/nesting", perf_nesting);
 355         g_test_add_func("/perf/yield", perf_yield);
 356         g_test_add_func("/perf/function-call", perf_baseline);
 357         g_test_add_func("/perf/cost", perf_cost);
 358     }
 359     return g_test_run();
 360 }