qemu/tests/test-coroutine.c
Gabriel Kerneis a9031675b9 coroutine: fix /perf/nesting coroutine benchmark
The /perf/nesting benchmark is broken because the counters are
not reset after each iteration. Therefore, nesting is done only
on the first iteration, and skipped on every other.

This patch fixes the issue, and reduces the number of iterations
to make it possible to run the benchmark in a reasonable amount of
time.

Signed-off-by: Gabriel Kerneis <gabriel@kerneis.info>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-19 13:21:41 +02:00

253 lines
5.4 KiB
C

/*
* Coroutine tests
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include <glib.h>
#include "block/coroutine.h"
/*
* Check that qemu_in_coroutine() works
*/
static void coroutine_fn verify_in_coroutine(void *opaque)
{
g_assert(qemu_in_coroutine());
}
static void test_in_coroutine(void)
{
Coroutine *coroutine;
g_assert(!qemu_in_coroutine());
coroutine = qemu_coroutine_create(verify_in_coroutine);
qemu_coroutine_enter(coroutine, NULL);
}
/*
* Check that qemu_coroutine_self() works
*/
static void coroutine_fn verify_self(void *opaque)
{
g_assert(qemu_coroutine_self() == opaque);
}
static void test_self(void)
{
Coroutine *coroutine;
coroutine = qemu_coroutine_create(verify_self);
qemu_coroutine_enter(coroutine, coroutine);
}
/*
* Check that coroutines may nest multiple levels
*/
typedef struct {
unsigned int n_enter; /* num coroutines entered */
unsigned int n_return; /* num coroutines returned */
unsigned int max; /* maximum level of nesting */
} NestData;
static void coroutine_fn nest(void *opaque)
{
NestData *nd = opaque;
nd->n_enter++;
if (nd->n_enter < nd->max) {
Coroutine *child;
child = qemu_coroutine_create(nest);
qemu_coroutine_enter(child, nd);
}
nd->n_return++;
}
static void test_nesting(void)
{
Coroutine *root;
NestData nd = {
.n_enter = 0,
.n_return = 0,
.max = 128,
};
root = qemu_coroutine_create(nest);
qemu_coroutine_enter(root, &nd);
/* Must enter and return from max nesting level */
g_assert_cmpint(nd.n_enter, ==, nd.max);
g_assert_cmpint(nd.n_return, ==, nd.max);
}
/*
* Check that yield/enter transfer control correctly
*/
static void coroutine_fn yield_5_times(void *opaque)
{
bool *done = opaque;
int i;
for (i = 0; i < 5; i++) {
qemu_coroutine_yield();
}
*done = true;
}
static void test_yield(void)
{
Coroutine *coroutine;
bool done = false;
int i = -1; /* one extra time to return from coroutine */
coroutine = qemu_coroutine_create(yield_5_times);
while (!done) {
qemu_coroutine_enter(coroutine, &done);
i++;
}
g_assert_cmpint(i, ==, 5); /* coroutine must yield 5 times */
}
/*
* Check that creation, enter, and return work
*/
static void coroutine_fn set_and_exit(void *opaque)
{
bool *done = opaque;
*done = true;
}
static void test_lifecycle(void)
{
Coroutine *coroutine;
bool done = false;
/* Create, enter, and return from coroutine */
coroutine = qemu_coroutine_create(set_and_exit);
qemu_coroutine_enter(coroutine, &done);
g_assert(done); /* expect done to be true (first time) */
/* Repeat to check that no state affects this test */
done = false;
coroutine = qemu_coroutine_create(set_and_exit);
qemu_coroutine_enter(coroutine, &done);
g_assert(done); /* expect done to be true (second time) */
}
/*
* Lifecycle benchmark
*/
static void coroutine_fn empty_coroutine(void *opaque)
{
/* Do nothing */
}
static void perf_lifecycle(void)
{
Coroutine *coroutine;
unsigned int i, max;
double duration;
max = 1000000;
g_test_timer_start();
for (i = 0; i < max; i++) {
coroutine = qemu_coroutine_create(empty_coroutine);
qemu_coroutine_enter(coroutine, NULL);
}
duration = g_test_timer_elapsed();
g_test_message("Lifecycle %u iterations: %f s\n", max, duration);
}
static void perf_nesting(void)
{
unsigned int i, maxcycles, maxnesting;
double duration;
maxcycles = 10000;
maxnesting = 1000;
Coroutine *root;
g_test_timer_start();
for (i = 0; i < maxcycles; i++) {
NestData nd = {
.n_enter = 0,
.n_return = 0,
.max = maxnesting,
};
root = qemu_coroutine_create(nest);
qemu_coroutine_enter(root, &nd);
}
duration = g_test_timer_elapsed();
g_test_message("Nesting %u iterations of %u depth each: %f s\n",
maxcycles, maxnesting, duration);
}
/*
* Yield benchmark
*/
static void coroutine_fn yield_loop(void *opaque)
{
unsigned int *counter = opaque;
while ((*counter) > 0) {
(*counter)--;
qemu_coroutine_yield();
}
}
static void perf_yield(void)
{
unsigned int i, maxcycles;
double duration;
maxcycles = 100000000;
i = maxcycles;
Coroutine *coroutine = qemu_coroutine_create(yield_loop);
g_test_timer_start();
while (i > 0) {
qemu_coroutine_enter(coroutine, &i);
}
duration = g_test_timer_elapsed();
g_test_message("Yield %u iterations: %f s\n",
maxcycles, duration);
}
int main(int argc, char **argv)
{
g_test_init(&argc, &argv, NULL);
g_test_add_func("/basic/lifecycle", test_lifecycle);
g_test_add_func("/basic/yield", test_yield);
g_test_add_func("/basic/nesting", test_nesting);
g_test_add_func("/basic/self", test_self);
g_test_add_func("/basic/in_coroutine", test_in_coroutine);
if (g_test_perf()) {
g_test_add_func("/perf/lifecycle", perf_lifecycle);
g_test_add_func("/perf/nesting", perf_nesting);
g_test_add_func("/perf/yield", perf_yield);
}
return g_test_run();
}