glib/tests/timeloop.c
Owen Taylor e2fd4e2bd0 Major change in API for creating sources to handle multiple main loops
Tue Dec  5 12:23:04 2000  Owen Taylor  <otaylor@redhat.com>

        * gmain.[hc]: Major change in API for creating sources
	to handle multiple main loops (GMainContext *).

	GSources are now exposed as GSource * and implemented
	with structure derivation.

	* giochannel.[ch]: Changed vtable for GIOChannel to correspond
	to the new mainloop API, add g_io_channel_create_watch().

	* gtypes.h: Move GTimeVal here.

	* gthread.h: Remove gmain.h include to avoid circularity.

        * giounix.c: Update for new GMain API.

	* giowin32.c: Update for new GMain API. (No check for
	proper compilation or working.)

	* timeloop.c timeloop-basic.c: A benchmarking program for
	the main loop comparing the main loop against a
	hand-written (timeloop-basic.c) variant.

	* tests/mainloop-test.c: New torture test of mainloop.

	* docs/Changes-2.0.txt: Started. Added text about
	changes to GMain.

	* gmain.c (g_main_add_poll_unlocked): Initial fd->revents
	to zero. (#8482, Benjamin Kahn)
2000-12-05 20:45:33 +00:00

214 lines
4.3 KiB
C

#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/resource.h>
#include <sys/time.h>
#include <glib.h>
static int n_children = 3;
static int n_active_children;
static int n_iters = 10000;
static GMainLoop *loop;
void
io_pipe (GIOChannel **channels)
{
int fds[2];
if (pipe(fds) < 0)
{
fprintf (stderr, "Cannot create pipe %s\n", g_strerror (errno));
exit (1);
}
channels[0] = g_io_channel_unix_new (fds[0]);
channels[1] = g_io_channel_unix_new (fds[1]);
}
gboolean
read_all (GIOChannel *channel, char *buf, int len)
{
int bytes_read = 0;
int count;
GIOError err;
while (bytes_read < len)
{
err = g_io_channel_read (channel, buf + bytes_read, len - bytes_read, &count);
if (err)
{
if (err != G_IO_ERROR_AGAIN)
return FALSE;
}
else if (count == 0)
return FALSE;
bytes_read += count;
}
return TRUE;
}
gboolean
write_all (GIOChannel *channel, char *buf, int len)
{
int bytes_written = 0;
int count;
GIOError err;
while (bytes_written < len)
{
err = g_io_channel_write (channel, buf + bytes_written, len - bytes_written, &count);
if (err && err != G_IO_ERROR_AGAIN)
return FALSE;
bytes_written += count;
}
return TRUE;
}
void
run_child (GIOChannel *in_channel, GIOChannel *out_channel)
{
int i;
int val = 1;
GTimer *timer = g_timer_new();
for (i = 0; i < n_iters; i++)
{
write_all (out_channel, (char *)&val, sizeof (val));
read_all (in_channel, (char *)&val, sizeof (val));
}
val = 0;
write_all (out_channel, (char *)&val, sizeof (val));
val = g_timer_elapsed (timer, NULL) * 1000;
write_all (out_channel, (char *)&val, sizeof (val));
g_timer_destroy (timer);
exit (0);
}
gboolean
input_callback (GIOChannel *source,
GIOCondition condition,
gpointer data)
{
int val;
GIOChannel *dest = (GIOChannel *)data;
if (!read_all (source, (char *)&val, sizeof(val)))
{
fprintf (stderr, "Unexpected EOF\n");
exit (1);
}
if (val)
{
write_all (dest, (char *)&val, sizeof(val));
return TRUE;
}
else
{
g_io_channel_close (source);
g_io_channel_close (dest);
g_io_channel_unref (source);
g_io_channel_unref (dest);
n_active_children--;
if (n_active_children == 0)
g_main_quit (loop);
return FALSE;
}
}
void
create_child ()
{
int pid;
GIOChannel *in_channels[2];
GIOChannel *out_channels[2];
io_pipe (in_channels);
io_pipe (out_channels);
pid = fork ();
if (pid > 0) /* Parent */
{
g_io_channel_close (in_channels[0]);
g_io_channel_close (out_channels[1]);
g_io_add_watch (out_channels[0], G_IO_IN | G_IO_HUP,
input_callback, in_channels[1]);
}
else if (pid == 0) /* Child */
{
g_io_channel_close (in_channels[1]);
g_io_channel_close (out_channels[0]);
setsid ();
run_child (in_channels[0], out_channels[1]);
}
else /* Error */
{
fprintf (stderr, "Cannot fork: %s\n", g_strerror (errno));
exit (1);
}
}
static double
difftimeval (struct timeval *old, struct timeval *new)
{
return
(new->tv_sec - old->tv_sec) * 1000. + (new->tv_usec - old->tv_usec) / 1000;
}
int
main (int argc, char **argv)
{
int i;
struct rusage old_usage;
struct rusage new_usage;
if (argc > 1)
n_children = atoi(argv[1]);
if (argc > 2)
n_iters = atoi(argv[2]);
printf ("Children: %d Iters: %d\n", n_children, n_iters);
n_active_children = n_children;
for (i = 0; i < n_children; i++)
create_child ();
getrusage (RUSAGE_SELF, &old_usage);
loop = g_main_new (FALSE);
g_main_run (loop);
getrusage (RUSAGE_SELF, &new_usage);
printf ("Elapsed user: %g\n",
difftimeval (&old_usage.ru_utime, &new_usage.ru_utime));
printf ("Elapsed system: %g\n",
difftimeval (&old_usage.ru_stime, &new_usage.ru_stime));
printf ("Elapsed total: %g\n",
difftimeval (&old_usage.ru_utime, &new_usage.ru_utime) +
difftimeval (&old_usage.ru_stime, &new_usage.ru_stime));
printf ("total / iteration: %g\n",
(difftimeval (&old_usage.ru_utime, &new_usage.ru_utime) +
difftimeval (&old_usage.ru_stime, &new_usage.ru_stime)) /
(n_iters * n_children));
return 0;
}