mutter/src/backends/native/meta-kms-device.c
Jonas Ådahl 27ed069766 kms/impl-device: Add deadline based KMS commit scheduling
This makes it possible to post KMS updates that will always defer until
just before the scanout deadline. This is useful to allow queuing cursor
updates where we don't want to post them to KMS immediately, but rather
wait until as late as possible to get lower latency.

We cannot delay primary plane compositions however, and this is due to
how the kernel may prioritize GPU work - not until a pipeline gets
attached to a atomic commit will it in some drivers get bumped to high
priority. This means we still need to post any update that depends on
OpenGL pipelines as soon as possible.

To avoid working on compositing, then getting stomped on the feet by the
deadline scheduler, the deadline timer is disarmed whenever there is a
frame currently being painted. This will still allow new cursor updates
to arrive during composition, but will delay the actual KMS commit until
the primary plane update has been posted.

Still, even for cursor-only we still need higher than default timing
capabilities, thus the deadline scheduler depends on the KMS thread
getting real-time scheduling priority. When the thread isn't realtime
scheduled, the KMS thread instead asks the main thread to "flush" the
commit as part of the regular frame update. A flushing update means one
that isn't set to always defer and has a latching CRTC.

The verbose KMS debug logging makes the processing take too long, making
us more likely to miss the deadline. Avoid this by increasing the
evasion length when debug logging is enabled. Not the best, but better
than changing the behavior completely.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2777>
2023-07-17 23:42:38 +02:00

738 lines
20 KiB
C

/*
* Copyright (C) 2019 Red Hat
* Copyright (C) 2019 DisplayLink (UK) Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*/
#include "config.h"
#include "backends/native/meta-kms-connector.h"
#include "backends/native/meta-kms-crtc.h"
#include "backends/native/meta-kms-device-private.h"
#include "backends/native/meta-kms-device.h"
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <xf86drm.h>
#include "backends/native/meta-backend-native-private.h"
#include "backends/native/meta-device-pool.h"
#include "backends/native/meta-kms-impl-device-atomic.h"
#include "backends/native/meta-kms-impl-device-dummy.h"
#include "backends/native/meta-kms-impl-device-simple.h"
#include "backends/native/meta-kms-impl-device.h"
#include "backends/native/meta-kms-impl.h"
#include "backends/native/meta-kms-plane.h"
#include "backends/native/meta-kms-private.h"
#include "backends/native/meta-kms-update-private.h"
enum
{
CRTC_NEEDS_FLUSH,
N_SIGNALS
};
static int signals[N_SIGNALS];
struct _MetaKmsDevice
{
GObject parent;
MetaKms *kms;
MetaKmsImplDevice *impl_device;
MetaKmsDeviceFlag flags;
char *path;
char *driver_name;
char *driver_description;
GList *crtcs;
GList *connectors;
GList *planes;
MetaKmsDeviceCaps caps;
GList *fallback_modes;
GHashTable *needs_flush_crtcs;
GMutex needs_flush_mutex;
};
G_DEFINE_TYPE (MetaKmsDevice, meta_kms_device, G_TYPE_OBJECT);
MetaKms *
meta_kms_device_get_kms (MetaKmsDevice *device)
{
return device->kms;
}
MetaKmsImplDevice *
meta_kms_device_get_impl_device (MetaKmsDevice *device)
{
return device->impl_device;
}
const char *
meta_kms_device_get_path (MetaKmsDevice *device)
{
return device->path;
}
const char *
meta_kms_device_get_driver_name (MetaKmsDevice *device)
{
return device->driver_name;
}
const char *
meta_kms_device_get_driver_description (MetaKmsDevice *device)
{
return device->driver_description;
}
MetaKmsDeviceFlag
meta_kms_device_get_flags (MetaKmsDevice *device)
{
return device->flags;
}
gboolean
meta_kms_device_get_cursor_size (MetaKmsDevice *device,
uint64_t *out_cursor_width,
uint64_t *out_cursor_height)
{
if (device->caps.has_cursor_size)
{
*out_cursor_width = device->caps.cursor_width;
*out_cursor_height = device->caps.cursor_height;
return TRUE;
}
else
{
return FALSE;
}
}
gboolean
meta_kms_device_prefers_shadow_buffer (MetaKmsDevice *device)
{
return device->caps.prefers_shadow_buffer;
}
gboolean
meta_kms_device_uses_monotonic_clock (MetaKmsDevice *device)
{
return device->caps.uses_monotonic_clock;
}
GList *
meta_kms_device_get_connectors (MetaKmsDevice *device)
{
return device->connectors;
}
MetaKmsCrtc *
meta_kms_device_find_crtc_in_impl (MetaKmsDevice *device,
uint32_t crtc_id)
{
MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
GList *l;
meta_assert_in_kms_impl (device->kms);
meta_assert_is_waiting_for_kms_impl_task (device->kms);
for (l = meta_kms_impl_device_peek_crtcs (impl_device); l; l = l->next)
{
MetaKmsCrtc *crtc = META_KMS_CRTC (l->data);
if (meta_kms_crtc_get_id (crtc) == crtc_id)
return crtc;
}
return NULL;
}
MetaKmsConnector *
meta_kms_device_find_connector_in_impl (MetaKmsDevice *device,
uint32_t connector_id)
{
MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
GList *l;
meta_assert_in_kms_impl (device->kms);
meta_assert_is_waiting_for_kms_impl_task (device->kms);
for (l = meta_kms_impl_device_peek_connectors (impl_device); l; l = l->next)
{
MetaKmsConnector *connector = META_KMS_CONNECTOR (l->data);
if (meta_kms_connector_get_id (connector) == connector_id)
return connector;
}
return NULL;
}
GList *
meta_kms_device_get_crtcs (MetaKmsDevice *device)
{
return device->crtcs;
}
GList *
meta_kms_device_get_planes (MetaKmsDevice *device)
{
return device->planes;
}
static MetaKmsPlane *
get_plane_with_type_for (MetaKmsDevice *device,
MetaKmsCrtc *crtc,
MetaKmsPlaneType type)
{
GList *l;
for (l = meta_kms_device_get_planes (device); l; l = l->next)
{
MetaKmsPlane *plane = l->data;
if (meta_kms_plane_get_plane_type (plane) != type)
continue;
if (meta_kms_plane_is_usable_with (plane, crtc))
return plane;
}
return NULL;
}
MetaKmsPlane *
meta_kms_device_get_primary_plane_for (MetaKmsDevice *device,
MetaKmsCrtc *crtc)
{
return get_plane_with_type_for (device, crtc, META_KMS_PLANE_TYPE_PRIMARY);
}
MetaKmsPlane *
meta_kms_device_get_cursor_plane_for (MetaKmsDevice *device,
MetaKmsCrtc *crtc)
{
return get_plane_with_type_for (device, crtc, META_KMS_PLANE_TYPE_CURSOR);
}
GList *
meta_kms_device_get_fallback_modes (MetaKmsDevice *device)
{
return device->fallback_modes;
}
static gpointer
disable_device_in_impl (MetaThreadImpl *thread_impl,
gpointer user_data,
GError **error)
{
MetaKmsImplDevice *impl_device = user_data;
meta_kms_impl_device_disable (impl_device);
return GINT_TO_POINTER (TRUE);
}
void
meta_kms_device_disable (MetaKmsDevice *device)
{
meta_assert_not_in_kms_impl (device->kms);
meta_kms_run_impl_task_sync (device->kms, disable_device_in_impl,
device->impl_device,
NULL);
}
MetaKmsResourceChanges
meta_kms_device_update_states_in_impl (MetaKmsDevice *device,
uint32_t crtc_id,
uint32_t connector_id)
{
MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
MetaKmsResourceChanges changes;
meta_assert_in_kms_impl (device->kms);
meta_assert_is_waiting_for_kms_impl_task (device->kms);
changes = meta_kms_impl_device_update_states (impl_device, crtc_id,
connector_id);
if (changes == META_KMS_RESOURCE_CHANGE_NONE)
return changes;
g_list_free (device->crtcs);
device->crtcs = meta_kms_impl_device_copy_crtcs (impl_device);
g_list_free (device->connectors);
device->connectors = meta_kms_impl_device_copy_connectors (impl_device);
g_list_free (device->planes);
device->planes = meta_kms_impl_device_copy_planes (impl_device);
return changes;
}
typedef struct
{
MetaKmsUpdate *update;
MetaKmsUpdateFlag flags;
} PostUpdateData;
static gpointer
process_sync_update_in_impl (MetaThreadImpl *thread_impl,
gpointer user_data,
GError **error)
{
PostUpdateData *data = user_data;
MetaKmsUpdate *update = data->update;
MetaKmsDevice *device = meta_kms_update_get_device (update);
MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
return meta_kms_impl_device_process_update (impl_device, update, data->flags);
}
MetaKmsFeedback *
meta_kms_device_process_update_sync (MetaKmsDevice *device,
MetaKmsUpdate *update,
MetaKmsUpdateFlag flags)
{
MetaKms *kms = META_KMS (meta_kms_device_get_kms (device));
PostUpdateData data;
data = (PostUpdateData) {
.update = update,
.flags = flags,
};
return meta_kms_run_impl_task_sync (kms, process_sync_update_in_impl,
&data, NULL);
}
static gpointer
process_async_update_in_impl (MetaThreadImpl *thread_impl,
gpointer user_data,
GError **error)
{
PostUpdateData *data = user_data;
MetaKmsUpdate *update = data->update;
MetaKmsDevice *device = meta_kms_update_get_device (update);
MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
meta_kms_impl_device_handle_update (impl_device, update, data->flags);
return GINT_TO_POINTER (TRUE);
}
void
meta_kms_device_post_update (MetaKmsDevice *device,
MetaKmsUpdate *update,
MetaKmsUpdateFlag flags)
{
MetaKms *kms = META_KMS (meta_kms_device_get_kms (device));
PostUpdateData *data;
g_return_if_fail (meta_kms_update_get_device (update) == device);
data = g_new0 (PostUpdateData, 1);
*data = (PostUpdateData) {
.update = update,
.flags = flags,
};
meta_thread_post_impl_task (META_THREAD (kms),
process_async_update_in_impl,
data, g_free,
NULL, NULL);
}
static gpointer
await_flush_in_impl (MetaThreadImpl *thread_impl,
gpointer user_data,
GError **error)
{
MetaKmsCrtc *crtc = META_KMS_CRTC (user_data);
MetaKmsDevice *device = meta_kms_crtc_get_device (crtc);
MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
meta_kms_impl_device_await_flush (impl_device, crtc);
return NULL;
}
void
meta_kms_device_await_flush (MetaKmsDevice *device,
MetaKmsCrtc *crtc)
{
MetaKms *kms = meta_kms_device_get_kms (device);
meta_thread_post_impl_task (META_THREAD (kms),
await_flush_in_impl,
crtc, NULL,
NULL, NULL);
}
static void
emit_crtc_needs_flush_in_main (MetaThread *thread,
gpointer user_data)
{
MetaKmsCrtc *crtc = user_data;
g_signal_emit (meta_kms_crtc_get_device (crtc),
signals[CRTC_NEEDS_FLUSH], 0, crtc);
}
void
meta_kms_device_set_needs_flush (MetaKmsDevice *device,
MetaKmsCrtc *crtc)
{
gboolean needs_flush;
g_mutex_lock (&device->needs_flush_mutex);
needs_flush = g_hash_table_add (device->needs_flush_crtcs, crtc);
g_mutex_unlock (&device->needs_flush_mutex);
if (needs_flush)
{
meta_kms_queue_callback (meta_kms_device_get_kms (device),
NULL, emit_crtc_needs_flush_in_main, crtc, NULL);
}
}
gboolean
meta_kms_device_handle_flush (MetaKmsDevice *device,
MetaKmsCrtc *crtc)
{
gboolean needs_flush;
g_mutex_lock (&device->needs_flush_mutex);
needs_flush = g_hash_table_remove (device->needs_flush_crtcs, crtc);
g_mutex_unlock (&device->needs_flush_mutex);
return needs_flush;
}
void
meta_kms_device_add_fake_plane_in_impl (MetaKmsDevice *device,
MetaKmsPlaneType plane_type,
MetaKmsCrtc *crtc)
{
MetaKmsImplDevice *impl_device = device->impl_device;
MetaKmsPlane *plane;
meta_assert_in_kms_impl (device->kms);
plane = meta_kms_impl_device_add_fake_plane (impl_device,
plane_type,
crtc);
device->planes = g_list_append (device->planes, plane);
}
typedef struct _CreateImplDeviceData
{
MetaKmsDevice *device;
const char *path;
MetaKmsDeviceFlag flags;
MetaKmsImplDevice *out_impl_device;
GList *out_crtcs;
GList *out_connectors;
GList *out_planes;
MetaKmsDeviceCaps out_caps;
GList *out_fallback_modes;
char *out_driver_name;
char *out_driver_description;
char *out_path;
} CreateImplDeviceData;
static const char *
impl_device_type_to_string (GType type)
{
if (type == META_TYPE_KMS_IMPL_DEVICE_ATOMIC)
return "atomic modesetting";
else if (type == META_TYPE_KMS_IMPL_DEVICE_SIMPLE)
return "legacy modesetting";
else if (type == META_TYPE_KMS_IMPL_DEVICE_DUMMY)
return "no modesetting";
g_assert_not_reached();
}
static MetaKmsImplDevice *
meta_create_kms_impl_device (MetaKmsDevice *device,
MetaKmsImpl *impl,
const char *path,
MetaKmsDeviceFlag flags,
GError **error)
{
meta_assert_in_kms_impl (meta_kms_impl_get_kms (impl));
const char *env_kms_mode;
enum {
KMS_MODE_AUTO,
KMS_MODE_ATOMIC,
KMS_MODE_SIMPLE,
KMS_MODE_HEADLESS,
} kms_mode;
meta_assert_in_kms_impl (meta_kms_impl_get_kms (impl));
env_kms_mode = g_getenv ("MUTTER_DEBUG_FORCE_KMS_MODE");
if (env_kms_mode)
{
if (g_strcmp0 (env_kms_mode, "auto") == 0)
{
kms_mode = KMS_MODE_AUTO;
}
else if (g_strcmp0 (env_kms_mode, "atomic") == 0)
{
kms_mode = KMS_MODE_ATOMIC;
}
else if (g_strcmp0 (env_kms_mode, "simple") == 0)
{
kms_mode = KMS_MODE_SIMPLE;
}
else if (g_strcmp0 (env_kms_mode, "headless") == 0)
{
kms_mode = KMS_MODE_HEADLESS;
}
else
{
g_warning ("Attempted to force invalid mode setting mode '%s",
env_kms_mode);
kms_mode = KMS_MODE_AUTO;
}
}
else
{
if (flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
kms_mode = KMS_MODE_HEADLESS;
else if (flags & META_KMS_DEVICE_FLAG_FORCE_LEGACY)
kms_mode = KMS_MODE_SIMPLE;
else
kms_mode = KMS_MODE_AUTO;
}
if (kms_mode == KMS_MODE_AUTO)
{
GType impl_device_types[] = {
META_TYPE_KMS_IMPL_DEVICE_ATOMIC,
META_TYPE_KMS_IMPL_DEVICE_SIMPLE,
};
int i;
for (i = 0; i < G_N_ELEMENTS (impl_device_types); i++)
{
MetaKmsImplDevice *impl_device;
g_autoptr (GError) local_error = NULL;
impl_device = g_initable_new (impl_device_types[i],
NULL, &local_error,
"device", device,
"impl", impl,
"path", path,
"flags", flags,
NULL);
if (impl_device)
return impl_device;
if (local_error->domain != META_KMS_ERROR)
{
g_warning ("Failed to open %s backend: %s",
impl_device_type_to_string (impl_device_types[i]),
local_error->message);
}
}
g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
"No suitable mode setting backend found");
return NULL;
}
else
{
GType type;
switch (kms_mode)
{
case KMS_MODE_ATOMIC:
type = META_TYPE_KMS_IMPL_DEVICE_ATOMIC;
break;
case KMS_MODE_SIMPLE:
type = META_TYPE_KMS_IMPL_DEVICE_SIMPLE;
break;
case KMS_MODE_HEADLESS:
type = META_TYPE_KMS_IMPL_DEVICE_DUMMY;
break;
default:
g_assert_not_reached ();
};
return g_initable_new (type, NULL, error,
"device", device,
"impl", impl,
"path", path,
"flags", flags,
NULL);
}
}
static gpointer
create_impl_device_in_impl (MetaThreadImpl *thread_impl,
gpointer user_data,
GError **error)
{
MetaKmsImpl *impl = META_KMS_IMPL (thread_impl);
CreateImplDeviceData *data = user_data;
MetaKmsImplDevice *impl_device;
impl_device = meta_create_kms_impl_device (data->device,
impl,
data->path,
data->flags,
error);
if (!impl_device)
return FALSE;
meta_kms_impl_add_impl_device (impl, impl_device);
data->out_impl_device = impl_device;
data->out_crtcs = meta_kms_impl_device_copy_crtcs (impl_device);
data->out_connectors = meta_kms_impl_device_copy_connectors (impl_device);
data->out_planes = meta_kms_impl_device_copy_planes (impl_device);
data->out_caps = *meta_kms_impl_device_get_caps (impl_device);
data->out_fallback_modes =
meta_kms_impl_device_copy_fallback_modes (impl_device);
data->out_driver_name =
g_strdup (meta_kms_impl_device_get_driver_name (impl_device));
data->out_driver_description =
g_strdup (meta_kms_impl_device_get_driver_description (impl_device));
data->out_path = g_strdup (meta_kms_impl_device_get_path (impl_device));
return GINT_TO_POINTER (TRUE);
}
MetaKmsDevice *
meta_kms_device_new (MetaKms *kms,
const char *path,
MetaKmsDeviceFlag flags,
GError **error)
{
MetaKmsDevice *device;
CreateImplDeviceData data;
device = g_object_new (META_TYPE_KMS_DEVICE, NULL);
device->kms = kms;
data = (CreateImplDeviceData) {
.device = device,
.path = path,
.flags = flags,
};
if (!meta_kms_run_impl_task_sync (kms, create_impl_device_in_impl, &data,
error))
{
g_object_unref (device);
return NULL;
}
device->impl_device = data.out_impl_device;
device->flags = flags;
device->path = g_strdup (path);
device->crtcs = data.out_crtcs;
device->connectors = data.out_connectors;
device->planes = data.out_planes;
device->caps = data.out_caps;
device->fallback_modes = data.out_fallback_modes;
device->driver_name = data.out_driver_name;
device->driver_description = data.out_driver_description;
free (device->path);
device->path = data.out_path;
if (device->caps.addfb2_modifiers)
device->flags |= META_KMS_DEVICE_FLAG_HAS_ADDFB2;
return device;
}
static gpointer
free_impl_device_in_impl (MetaThreadImpl *thread_impl,
gpointer user_data,
GError **error)
{
MetaKmsImplDevice *impl_device = user_data;
g_object_unref (impl_device);
return GINT_TO_POINTER (TRUE);
}
static void
meta_kms_device_finalize (GObject *object)
{
MetaKmsDevice *device = META_KMS_DEVICE (object);
g_free (device->path);
g_free (device->driver_name);
g_free (device->driver_description);
g_list_free (device->fallback_modes);
g_list_free (device->crtcs);
g_list_free (device->connectors);
g_list_free (device->planes);
if (device->impl_device)
{
meta_kms_run_impl_task_sync (device->kms, free_impl_device_in_impl,
device->impl_device,
NULL);
}
g_mutex_clear (&device->needs_flush_mutex);
g_hash_table_unref (device->needs_flush_crtcs);
G_OBJECT_CLASS (meta_kms_device_parent_class)->finalize (object);
}
static void
meta_kms_device_init (MetaKmsDevice *device)
{
device->needs_flush_crtcs = g_hash_table_new (NULL, NULL);
g_mutex_init (&device->needs_flush_mutex);
}
static void
meta_kms_device_class_init (MetaKmsDeviceClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->finalize = meta_kms_device_finalize;
signals[CRTC_NEEDS_FLUSH] =
g_signal_new ("crtc-needs-flush",
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 1,
META_TYPE_KMS_CRTC);
}