mirror of
https://gitlab.gnome.org/GNOME/glib.git
synced 2025-03-14 19:55:12 +01:00
Revert "GCancellable: Use per-instance mutex logic instead of global critical sections"
This reverts commit 3a07b2abd4006da33cdfb0916b266a21070a47d6.
This commit is contained in:
Michael Catanzaro
parent
aff5363fe0
commit
a7affddab7
@ -1,7 +1,6 @@
|
||||
/* GIO - GLib Input, Output and Streaming Library
|
||||
*
|
||||
* Copyright (C) 2006-2007 Red Hat, Inc.
|
||||
* Copyright (C) 2022-2024 Canonical, Ltd.
|
||||
*
|
||||
* SPDX-License-Identifier: LGPL-2.1-or-later
|
||||
*
|
||||
@ -19,7 +18,6 @@
|
||||
* Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* Author: Alexander Larsson <alexl@redhat.com>
|
||||
* Author: Marco Trevisan <marco.trevisan@canonical.com>
|
||||
*/
|
||||
|
||||
#include "config.h"
|
||||
@ -47,12 +45,14 @@ enum {
|
||||
|
||||
struct _GCancellablePrivate
|
||||
{
|
||||
/* Atomic so that we don't require holding global mutexes for independent ops. */
|
||||
/* Atomic so that g_cancellable_is_cancelled does not require holding the mutex. */
|
||||
gboolean cancelled;
|
||||
int cancelled_running;
|
||||
/* Access to fields below is protected by cancellable_mutex. */
|
||||
guint cancelled_running : 1;
|
||||
guint cancelled_running_waiting : 1;
|
||||
unsigned cancelled_emissions;
|
||||
unsigned cancelled_emissions_waiting : 1;
|
||||
|
||||
/* Access to fields below is protected by cancellable's mutex. */
|
||||
GMutex mutex;
|
||||
guint fd_refcount;
|
||||
GWakeup *wakeup;
|
||||
};
|
||||
@ -62,6 +62,7 @@ static guint signals[LAST_SIGNAL] = { 0 };
|
||||
G_DEFINE_TYPE_WITH_PRIVATE (GCancellable, g_cancellable, G_TYPE_OBJECT)
|
||||
|
||||
static GPrivate current_cancellable;
|
||||
static GMutex cancellable_mutex;
|
||||
static GCond cancellable_cond;
|
||||
|
||||
static void
|
||||
@ -69,15 +70,9 @@ g_cancellable_finalize (GObject *object)
|
||||
{
|
||||
GCancellable *cancellable = G_CANCELLABLE (object);
|
||||
|
||||
/* We're at finalization phase, so only one thread can be here.
|
||||
* Thus there's no need to lock. In case something is locking us, then we've
|
||||
* a bug, and g_mutex_clear() will make this clear aborting.
|
||||
*/
|
||||
if (cancellable->priv->wakeup)
|
||||
GLIB_PRIVATE_CALL (g_wakeup_free) (cancellable->priv->wakeup);
|
||||
|
||||
g_mutex_clear (&cancellable->priv->mutex);
|
||||
|
||||
G_OBJECT_CLASS (g_cancellable_parent_class)->finalize (object);
|
||||
}
|
||||
|
||||
@ -159,8 +154,6 @@ static void
|
||||
g_cancellable_init (GCancellable *cancellable)
|
||||
{
|
||||
cancellable->priv = g_cancellable_get_instance_private (cancellable);
|
||||
|
||||
g_mutex_init (&cancellable->priv->mutex);
|
||||
}
|
||||
|
||||
/**
|
||||
@ -272,17 +265,28 @@ g_cancellable_reset (GCancellable *cancellable)
|
||||
|
||||
g_return_if_fail (G_IS_CANCELLABLE (cancellable));
|
||||
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
priv = cancellable->priv;
|
||||
|
||||
g_mutex_lock (&priv->mutex);
|
||||
while (priv->cancelled_running || priv->cancelled_emissions > 0)
|
||||
{
|
||||
if (priv->cancelled_running)
|
||||
priv->cancelled_running_waiting = TRUE;
|
||||
|
||||
if (g_atomic_int_compare_and_exchange (&priv->cancelled, TRUE, FALSE))
|
||||
if (priv->cancelled_emissions > 0)
|
||||
priv->cancelled_emissions_waiting = TRUE;
|
||||
|
||||
g_cond_wait (&cancellable_cond, &cancellable_mutex);
|
||||
}
|
||||
|
||||
if (g_atomic_int_exchange (&priv->cancelled, FALSE))
|
||||
{
|
||||
if (priv->wakeup)
|
||||
GLIB_PRIVATE_CALL (g_wakeup_acknowledge) (priv->wakeup);
|
||||
}
|
||||
|
||||
g_mutex_unlock (&priv->mutex);
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
}
|
||||
|
||||
/**
|
||||
@ -400,29 +404,26 @@ g_cancellable_get_fd (GCancellable *cancellable)
|
||||
gboolean
|
||||
g_cancellable_make_pollfd (GCancellable *cancellable, GPollFD *pollfd)
|
||||
{
|
||||
GCancellablePrivate *priv;
|
||||
|
||||
g_return_val_if_fail (pollfd != NULL, FALSE);
|
||||
if (cancellable == NULL)
|
||||
return FALSE;
|
||||
g_return_val_if_fail (G_IS_CANCELLABLE (cancellable), FALSE);
|
||||
|
||||
priv = cancellable->priv;
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
g_mutex_lock (&priv->mutex);
|
||||
cancellable->priv->fd_refcount++;
|
||||
|
||||
if ((priv->fd_refcount++) == 0)
|
||||
if (cancellable->priv->wakeup == NULL)
|
||||
{
|
||||
priv->wakeup = GLIB_PRIVATE_CALL (g_wakeup_new) ();
|
||||
cancellable->priv->wakeup = GLIB_PRIVATE_CALL (g_wakeup_new) ();
|
||||
|
||||
if (g_atomic_int_get (&priv->cancelled))
|
||||
GLIB_PRIVATE_CALL (g_wakeup_signal) (priv->wakeup);
|
||||
if (g_atomic_int_get (&cancellable->priv->cancelled))
|
||||
GLIB_PRIVATE_CALL (g_wakeup_signal) (cancellable->priv->wakeup);
|
||||
}
|
||||
|
||||
g_assert (priv->wakeup);
|
||||
GLIB_PRIVATE_CALL (g_wakeup_get_pollfd) (priv->wakeup, pollfd);
|
||||
GLIB_PRIVATE_CALL (g_wakeup_get_pollfd) (cancellable->priv->wakeup, pollfd);
|
||||
|
||||
g_mutex_unlock (&priv->mutex);
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
|
||||
return TRUE;
|
||||
}
|
||||
@ -446,22 +447,26 @@ g_cancellable_make_pollfd (GCancellable *cancellable, GPollFD *pollfd)
|
||||
void
|
||||
g_cancellable_release_fd (GCancellable *cancellable)
|
||||
{
|
||||
GCancellablePrivate *priv;
|
||||
|
||||
if (cancellable == NULL)
|
||||
return;
|
||||
|
||||
g_return_if_fail (G_IS_CANCELLABLE (cancellable));
|
||||
|
||||
g_mutex_lock (&cancellable->priv->mutex);
|
||||
priv = cancellable->priv;
|
||||
|
||||
g_assert (cancellable->priv->fd_refcount > 0);
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
g_assert (priv->fd_refcount > 0);
|
||||
|
||||
if ((cancellable->priv->fd_refcount--) == 1)
|
||||
priv->fd_refcount--;
|
||||
if (priv->fd_refcount == 0)
|
||||
{
|
||||
GLIB_PRIVATE_CALL (g_wakeup_free) (cancellable->priv->wakeup);
|
||||
cancellable->priv->wakeup = NULL;
|
||||
GLIB_PRIVATE_CALL (g_wakeup_free) (priv->wakeup);
|
||||
priv->wakeup = NULL;
|
||||
}
|
||||
|
||||
g_mutex_unlock (&cancellable->priv->mutex);
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
}
|
||||
|
||||
/**
|
||||
@ -490,31 +495,37 @@ g_cancellable_cancel (GCancellable *cancellable)
|
||||
{
|
||||
GCancellablePrivate *priv;
|
||||
|
||||
if (cancellable == NULL || g_atomic_int_get (&cancellable->priv->cancelled))
|
||||
if (cancellable == NULL || g_cancellable_is_cancelled (cancellable))
|
||||
return;
|
||||
|
||||
priv = cancellable->priv;
|
||||
|
||||
g_mutex_lock (&priv->mutex);
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
if (!g_atomic_int_compare_and_exchange (&priv->cancelled, FALSE, TRUE))
|
||||
if (g_atomic_int_exchange (&priv->cancelled, TRUE))
|
||||
{
|
||||
g_mutex_unlock (&priv->mutex);
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
return;
|
||||
}
|
||||
|
||||
g_atomic_int_inc (&priv->cancelled_running);
|
||||
priv->cancelled_running = TRUE;
|
||||
|
||||
if (priv->wakeup)
|
||||
GLIB_PRIVATE_CALL (g_wakeup_signal) (priv->wakeup);
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
|
||||
g_object_ref (cancellable);
|
||||
g_signal_emit (cancellable, signals[CANCELLED], 0);
|
||||
|
||||
if (g_atomic_int_dec_and_test (&priv->cancelled_running))
|
||||
g_cond_broadcast (&cancellable_cond);
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
g_mutex_unlock (&priv->mutex);
|
||||
priv->cancelled_running = FALSE;
|
||||
if (priv->cancelled_running_waiting)
|
||||
g_cond_broadcast (&cancellable_cond);
|
||||
priv->cancelled_running_waiting = FALSE;
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
|
||||
g_object_unref (cancellable);
|
||||
}
|
||||
@ -562,7 +573,7 @@ g_cancellable_connect (GCancellable *cancellable,
|
||||
|
||||
g_return_val_if_fail (G_IS_CANCELLABLE (cancellable), 0);
|
||||
|
||||
g_mutex_lock (&cancellable->priv->mutex);
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
if (g_atomic_int_get (&cancellable->priv->cancelled))
|
||||
{
|
||||
@ -572,10 +583,23 @@ g_cancellable_connect (GCancellable *cancellable,
|
||||
_callback = (void *)callback;
|
||||
id = 0;
|
||||
|
||||
cancellable->priv->cancelled_emissions++;
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
|
||||
_callback (cancellable, data);
|
||||
|
||||
if (data_destroy_func)
|
||||
data_destroy_func (data);
|
||||
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
if (cancellable->priv->cancelled_emissions_waiting)
|
||||
g_cond_broadcast (&cancellable_cond);
|
||||
|
||||
cancellable->priv->cancelled_emissions--;
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
}
|
||||
else
|
||||
{
|
||||
@ -583,9 +607,10 @@ g_cancellable_connect (GCancellable *cancellable,
|
||||
callback, data,
|
||||
(GClosureNotify) data_destroy_func,
|
||||
G_CONNECT_DEFAULT);
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
}
|
||||
|
||||
g_mutex_unlock (&cancellable->priv->mutex);
|
||||
|
||||
return id;
|
||||
}
|
||||
@ -621,26 +646,33 @@ g_cancellable_disconnect (GCancellable *cancellable,
|
||||
if (handler_id == 0 || cancellable == NULL)
|
||||
return;
|
||||
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
priv = cancellable->priv;
|
||||
|
||||
g_mutex_lock (&priv->mutex);
|
||||
while (priv->cancelled_running || priv->cancelled_emissions)
|
||||
{
|
||||
if (priv->cancelled_running)
|
||||
priv->cancelled_running_waiting = TRUE;
|
||||
|
||||
while (g_atomic_int_get (&priv->cancelled_running) != 0)
|
||||
g_cond_wait (&cancellable_cond, &priv->mutex);
|
||||
if (priv->cancelled_emissions)
|
||||
priv->cancelled_emissions_waiting = TRUE;
|
||||
|
||||
g_mutex_unlock (&priv->mutex);
|
||||
g_cond_wait (&cancellable_cond, &cancellable_mutex);
|
||||
}
|
||||
|
||||
g_signal_handler_disconnect (cancellable, handler_id);
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
}
|
||||
|
||||
typedef struct {
|
||||
GSource source;
|
||||
|
||||
/* Atomic: */
|
||||
GCancellable *cancellable;
|
||||
gulong cancelled_handler;
|
||||
/* Atomic: */
|
||||
gboolean cancelled_callback_called;
|
||||
/* Protected by cancellable_mutex: */
|
||||
gboolean resurrected_during_cancellation;
|
||||
} GCancellableSource;
|
||||
|
||||
/*
|
||||
@ -660,35 +692,27 @@ cancellable_source_cancelled (GCancellable *cancellable,
|
||||
{
|
||||
GSource *source = user_data;
|
||||
GCancellableSource *cancellable_source = (GCancellableSource *) source;
|
||||
gboolean callback_was_not_called;
|
||||
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
/* Drop the reference added in cancellable_source_dispose(); see the comment there.
|
||||
* The reference must be dropped after unlocking @cancellable_mutex since
|
||||
* it could be the final reference, and the dispose function takes
|
||||
* @cancellable_mutex. */
|
||||
if (cancellable_source->resurrected_during_cancellation)
|
||||
{
|
||||
cancellable_source->resurrected_during_cancellation = FALSE;
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
g_source_unref (source);
|
||||
return;
|
||||
}
|
||||
|
||||
g_source_ref (source);
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
g_source_set_ready_time (source, 0);
|
||||
|
||||
callback_was_not_called = g_atomic_int_compare_and_exchange (
|
||||
&cancellable_source->cancelled_callback_called, FALSE, TRUE);
|
||||
g_assert (callback_was_not_called);
|
||||
|
||||
g_source_unref (source);
|
||||
}
|
||||
|
||||
static gboolean
|
||||
cancellable_source_prepare (GSource *source,
|
||||
gint *timeout)
|
||||
{
|
||||
GCancellableSource *cancellable_source = (GCancellableSource *) source;
|
||||
GCancellable *cancellable;
|
||||
|
||||
if (timeout)
|
||||
*timeout = -1;
|
||||
|
||||
cancellable = g_atomic_pointer_get (&cancellable_source->cancellable);
|
||||
if (cancellable && !g_atomic_int_get (&cancellable->priv->cancelled_running))
|
||||
g_atomic_int_set (&cancellable_source->cancelled_callback_called, FALSE);
|
||||
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
static gboolean
|
||||
cancellable_source_dispatch (GSource *source,
|
||||
GSourceFunc callback,
|
||||
@ -705,13 +729,12 @@ static void
|
||||
cancellable_source_dispose (GSource *source)
|
||||
{
|
||||
GCancellableSource *cancellable_source = (GCancellableSource *)source;
|
||||
GCancellable *cancellable;
|
||||
|
||||
cancellable = g_atomic_pointer_exchange (&cancellable_source->cancellable, NULL);
|
||||
g_mutex_lock (&cancellable_mutex);
|
||||
|
||||
if (cancellable)
|
||||
if (cancellable_source->cancellable)
|
||||
{
|
||||
if (g_atomic_int_get (&cancellable->priv->cancelled_running))
|
||||
if (cancellable_source->cancellable->priv->cancelled_running)
|
||||
{
|
||||
/* There can be a race here: if thread A has called
|
||||
* g_cancellable_cancel() and has got as far as committing to call
|
||||
@ -723,21 +746,21 @@ cancellable_source_dispose (GSource *source)
|
||||
* will then be left in a state where it’s committed to using a
|
||||
* dangling GCancellableSource pointer.
|
||||
*
|
||||
* Eliminate that race by waiting to ensure that our cancelled
|
||||
* callback has been called, keeping a temporary ref, so that
|
||||
* there's no risk that we're unreffing something that is still
|
||||
* going to be used.
|
||||
* Eliminate that race by resurrecting the #GSource temporarily, and
|
||||
* then dropping that reference in cancellable_source_cancelled(),
|
||||
* which should be guaranteed to fire because we’re inside a
|
||||
* @cancelled_running block.
|
||||
*/
|
||||
|
||||
g_source_ref (source);
|
||||
while (!g_atomic_int_get (&cancellable_source->cancelled_callback_called))
|
||||
;
|
||||
g_source_unref (source);
|
||||
cancellable_source->resurrected_during_cancellation = TRUE;
|
||||
}
|
||||
|
||||
g_clear_signal_handler (&cancellable_source->cancelled_handler, cancellable);
|
||||
g_object_unref (cancellable);
|
||||
g_clear_signal_handler (&cancellable_source->cancelled_handler,
|
||||
cancellable_source->cancellable);
|
||||
g_clear_object (&cancellable_source->cancellable);
|
||||
}
|
||||
|
||||
g_mutex_unlock (&cancellable_mutex);
|
||||
}
|
||||
|
||||
static gboolean
|
||||
@ -766,7 +789,7 @@ cancellable_source_closure_callback (GCancellable *cancellable,
|
||||
|
||||
static GSourceFuncs cancellable_source_funcs =
|
||||
{
|
||||
cancellable_source_prepare,
|
||||
NULL,
|
||||
NULL,
|
||||
cancellable_source_dispatch,
|
||||
NULL,
|
||||
|
||||
@ -261,6 +261,11 @@ threaded_dispose_thread_cb (gpointer user_data)
|
||||
static void
|
||||
test_cancellable_source_threaded_dispose (void)
|
||||
{
|
||||
#ifdef _GLIB_ADDRESS_SANITIZER
|
||||
g_test_incomplete ("FIXME: Leaks lots of GCancellableSource objects, see glib#2309");
|
||||
(void) cancelled_cb;
|
||||
(void) threaded_dispose_thread_cb;
|
||||
#else
|
||||
ThreadedDisposeData data;
|
||||
GThread *thread = NULL;
|
||||
guint i;
|
||||
@ -270,10 +275,6 @@ test_cancellable_source_threaded_dispose (void)
|
||||
"(in one thread) and cancelling the GCancellable it refers "
|
||||
"to (in another thread)");
|
||||
g_test_bug ("https://gitlab.gnome.org/GNOME/glib/issues/1841");
|
||||
#ifdef _GLIB_ADDRESS_SANITIZER
|
||||
g_test_message ("We also ensure that no GCancellableSource are leaked");
|
||||
g_test_bug ("https://gitlab.gnome.org/GNOME/glib/issues/2309");
|
||||
#endif
|
||||
|
||||
/* Create a new thread and wait until it’s ready to execute. Each iteration of
|
||||
* the test will pass it a new #GCancellableSource. */
|
||||
@ -334,6 +335,7 @@ test_cancellable_source_threaded_dispose (void)
|
||||
g_cond_clear (&data.cond);
|
||||
|
||||
g_ptr_array_unref (cancellables_pending_unref);
|
||||
#endif
|
||||
}
|
||||
|
||||
static void
|
||||
|
||||
@ -1007,16 +1007,17 @@ test_dbus_roundtrip (void)
|
||||
static void
|
||||
test_dbus_peer_roundtrip (void)
|
||||
{
|
||||
PeerConnection peer;
|
||||
|
||||
#ifdef _GLIB_ADDRESS_SANITIZER
|
||||
g_test_message ("Ensure that no GCancellableSource are leaked");
|
||||
g_test_bug ("https://gitlab.gnome.org/GNOME/glib/issues/2313");
|
||||
#endif
|
||||
g_test_incomplete ("FIXME: Leaks a GCancellableSource, see glib#2313");
|
||||
(void) peer_connection_up;
|
||||
(void) peer_connection_down;
|
||||
#else
|
||||
PeerConnection peer;
|
||||
|
||||
peer_connection_up (&peer);
|
||||
do_roundtrip (peer.server_connection, peer.client_connection);
|
||||
peer_connection_down (&peer);
|
||||
#endif
|
||||
}
|
||||
|
||||
static gint items_changed_count;
|
||||
@ -1145,16 +1146,17 @@ test_dbus_subscriptions (void)
|
||||
static void
|
||||
test_dbus_peer_subscriptions (void)
|
||||
{
|
||||
PeerConnection peer;
|
||||
|
||||
#ifdef _GLIB_ADDRESS_SANITIZER
|
||||
g_test_message ("Ensure that no GCancellableSource are leaked");
|
||||
g_test_bug ("https://gitlab.gnome.org/GNOME/glib/issues/2313");
|
||||
#endif
|
||||
g_test_incomplete ("FIXME: Leaks a GCancellableSource, see glib#2313");
|
||||
(void) peer_connection_up;
|
||||
(void) peer_connection_down;
|
||||
#else
|
||||
PeerConnection peer;
|
||||
|
||||
peer_connection_up (&peer);
|
||||
do_subscriptions (peer.server_connection, peer.client_connection);
|
||||
peer_connection_down (&peer);
|
||||
#endif
|
||||
}
|
||||
|
||||
static void
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user