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  * Lifecycle benchmark
 155  */
 156
 157 static void coroutine_fn empty_coroutine(void *opaque)
 158 {
 159     /* Do nothing */
 160 }
 161
 162 static void perf_lifecycle(void)
 163 {
 164     Coroutine *coroutine;
 165     unsigned int i, max;
 166     double duration;
 167
 168     max = 1000000;
 169
 170     g_test_timer_start();
 171     for (i = 0; i < max; i++) {
 172         coroutine = qemu_coroutine_create(empty_coroutine);
 173         qemu_coroutine_enter(coroutine, NULL);
 174     }
 175     duration = g_test_timer_elapsed();
 176
 177     g_test_message("Lifecycle %u iterations: %f s\n", max, duration);
 178 }
 179
 180 static void perf_nesting(void)
 181 {
 182     unsigned int i, maxcycles, maxnesting;
 183     double duration;
 184
 185     maxcycles = 100000000;
 186     maxnesting = 1000;
 187     Coroutine *root;
 188     NestData nd = {
 189         .n_enter  = 0,
 190         .n_return = 0,
 191         .max      = maxnesting,
 192     };
 193
 194     g_test_timer_start();
 195     for (i = 0; i < maxcycles; i++) {
 196         root = qemu_coroutine_create(nest);
 197         qemu_coroutine_enter(root, &nd);
 198     }
 199     duration = g_test_timer_elapsed();
 200
 201     g_test_message("Nesting %u iterations of %u depth each: %f s\n",
 202         maxcycles, maxnesting, duration);
 203 }
 204
 205
 206 int main(int argc, char **argv)
 207 {
 208     g_test_init(&argc, &argv, NULL);
 209     g_test_add_func("/basic/lifecycle", test_lifecycle);
 210     g_test_add_func("/basic/yield", test_yield);
 211     g_test_add_func("/basic/nesting", test_nesting);
 212     g_test_add_func("/basic/self", test_self);
 213     g_test_add_func("/basic/in_coroutine", test_in_coroutine);
 214     if (g_test_perf()) {
 215         g_test_add_func("/perf/lifecycle", perf_lifecycle);
 216         g_test_add_func("/perf/nesting", perf_nesting);
 217     }
 218     return g_test_run();
 219 }