mutter/src/backends/native/meta-kms-impl.h

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backends/native: Add basic KMS abstraction building blocks The intention with KMS abstraction is to hide away accessing the drm functions behind an API that allows us to have different kind of KMS implementations, including legacy non-atomic and atomic. The intention is also that the code interacting with the drm device should be able to be run in a different thread than the main thread. This means that we need to make sure that all drm*() API usage must only occur from within tasks that eventually can be run in the dedicated thread. The idea here is that MetaKms provides a outward facing API other places of mutter can use (e.g. MetaGpuKms and friends), while MetaKmsImpl is an internal implementation that only gets interacted with via "tasks" posted via the MetaKms object. These tasks will in the future potentially be run on the dedicated KMS thread. Initially, we don't create any new threads. Likewise, MetaKmsDevice is a outward facing representation of a KMS device, while MetaKmsImplDevice is the corresponding implementation, which only runs from within the MetaKmsImpl tasks. This commit only moves opening and closing the device to this new API, while leaking the fd outside of the impl enclosure, effectively making the isolation for drm*() calls pointless. This, however, is necessary to allow gradual porting of drm interaction, and eventually the file descriptor in MetaGpuKms will be removed. For now, it's harmless, since everything still run in the main thread. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-01-29 04:24:44 -05:00
/*
* Copyright (C) 2018 Red Hat
kms: Process impl idle callbacks before pre dispatch flush mode_set_fallback() schedules a call to mode_set_fallback_feedback_idle(), but it is possible for Mutter to repaint before the idle callbacks are dispatched. If that happens, mode_set_fallback_feedback_idle() does not get called before Mutter enters wait_for_pending_flips(), leading to a deadlock. Add the needed interfaces so that meta_kms_device_dispatch_sync() can flush all the implementation idle callbacks before it checks if any "events" are available. This prevents the deadlock by ensuring mode_set_fallback_feedback_idle() does get called before potentially waiting for actual DRM events. Presumably this call would not be needed if the implementation was running in its own thread, since it would eventually dispatch its idle callbacks before going to sleep polling on the DRM fd. This call might even be unnecessary overhead in that case, synchronizing with the implementation thread needlessly. But the thread does not exist yet, so this is needed for now. This is part 1 of 2 fixing a complete desktop freeze when drmModePageFlip() fails with EINVAL and the fallback to drmModeSetCrtc() succeeds but the success is not registered correctly as completed "flip". The freeze occurs under wait_for_pending_flips() which calls down into meta_kms_impl_device_dispatch() which ends up poll()'ing the DRM fd even though drmModeSetCrtc() will not produce a DRM event, hence the poll() never returns. The freeze was observed when hotplugging a DisplayLink dock for the first time on Ubuntu 19.10. CC stable: gnome-3-34 https://gitlab.gnome.org/GNOME/mutter/merge_requests/953
2019-11-29 05:50:30 -05:00
* Copyright (C) 2019 DisplayLink (UK) Ltd.
backends/native: Add basic KMS abstraction building blocks The intention with KMS abstraction is to hide away accessing the drm functions behind an API that allows us to have different kind of KMS implementations, including legacy non-atomic and atomic. The intention is also that the code interacting with the drm device should be able to be run in a different thread than the main thread. This means that we need to make sure that all drm*() API usage must only occur from within tasks that eventually can be run in the dedicated thread. The idea here is that MetaKms provides a outward facing API other places of mutter can use (e.g. MetaGpuKms and friends), while MetaKmsImpl is an internal implementation that only gets interacted with via "tasks" posted via the MetaKms object. These tasks will in the future potentially be run on the dedicated KMS thread. Initially, we don't create any new threads. Likewise, MetaKmsDevice is a outward facing representation of a KMS device, while MetaKmsImplDevice is the corresponding implementation, which only runs from within the MetaKmsImpl tasks. This commit only moves opening and closing the device to this new API, while leaking the fd outside of the impl enclosure, effectively making the isolation for drm*() calls pointless. This, however, is necessary to allow gradual porting of drm interaction, and eventually the file descriptor in MetaGpuKms will be removed. For now, it's harmless, since everything still run in the main thread. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-01-29 04:24:44 -05:00
*
* 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.
*/
#ifndef META_KMS_IMPL_H
#define META_KMS_IMPL_H
#include "backends/native/meta-kms-impl-device.h"
backend/native: Add and use transactional KMS API This commit introduces, and makes use of, a transactional API used for setting up KMS state, later to be applied, potentially atomically. From an API point of view, so is always the case, but in the current implementation, it still uses legacy drmMode* API to apply the state non-atomically. The API consists of various buliding blocks: * MetaKmsUpdate - a set of configuration changes, the higher level handle for handing over configuration to the impl backend. It's used to set mode, assign framebuffers to planes, queue page flips and set connector properties. * MetaKmsPlaneAssignment - the assignment of a framebuffer to a plane. Currently used to map a framebuffer to the primary plane of a CRTC. In the legacy KMS implementation, the plane assignment is used to derive the framebuffer used for mode setting and page flipping. This also means various high level changes: State, excluding configuring the cursor plane and creating/destroying DRM framebuffer handles, are applied in the end of a clutter frame, in one go. From an API point of view, this is done atomically, but as mentioned, only the non-atomic implementation exists so far. From MetaRendererNative's point of view, a page flip now initially always succeeds; the handling of EBUSY errors are done asynchronously in the MetaKmsImpl backend (still by retrying at refresh rate, but postponing flip callbacks instead of manipulating the frame clock). Handling of falling back to mode setting instead of page flipping is notified after the fact by a more precise page flip feedback API. EGLStream based page flipping relies on the impl backend not being atomic, as the page flipping is done in the EGLStream backend (e.g. nvidia driver). It uses a 'custom' page flip queueing method, keeping the EGLStream logic inside meta-renderer-native.c. Page flip handling is moved to meta-kms-impl-device.c from meta-gpu-kms.c. It goes via an extra idle callback before reaching meta-renderer-native.c to make sure callbacks are invoked outside of the impl context. While dummy power save page flipping is kept in meta-renderer-native.c, the EBUSY handling is moved to meta-kms-impl-simple.c. Instead of freezing the frame clock, actual page flip callbacks are postponed until all EBUSY retries have either succeeded or failed due to some other error than EBUSY. This effectively inhibits new frames to be drawn, meaning we won't stall waiting on the file descriptor for pending page flips. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-04-04 16:36:41 -04:00
#include "backends/native/meta-kms-page-flip-private.h"
backends/native: Add basic KMS abstraction building blocks The intention with KMS abstraction is to hide away accessing the drm functions behind an API that allows us to have different kind of KMS implementations, including legacy non-atomic and atomic. The intention is also that the code interacting with the drm device should be able to be run in a different thread than the main thread. This means that we need to make sure that all drm*() API usage must only occur from within tasks that eventually can be run in the dedicated thread. The idea here is that MetaKms provides a outward facing API other places of mutter can use (e.g. MetaGpuKms and friends), while MetaKmsImpl is an internal implementation that only gets interacted with via "tasks" posted via the MetaKms object. These tasks will in the future potentially be run on the dedicated KMS thread. Initially, we don't create any new threads. Likewise, MetaKmsDevice is a outward facing representation of a KMS device, while MetaKmsImplDevice is the corresponding implementation, which only runs from within the MetaKmsImpl tasks. This commit only moves opening and closing the device to this new API, while leaking the fd outside of the impl enclosure, effectively making the isolation for drm*() calls pointless. This, however, is necessary to allow gradual porting of drm interaction, and eventually the file descriptor in MetaGpuKms will be removed. For now, it's harmless, since everything still run in the main thread. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-01-29 04:24:44 -05:00
#include "backends/native/meta-kms.h"
#define META_TYPE_KMS_IMPL (meta_kms_impl_get_type ())
G_DECLARE_DERIVABLE_TYPE (MetaKmsImpl, meta_kms_impl,
META, KMS_IMPL, GObject)
struct _MetaKmsImplClass
{
GObjectClass parent_class;
backend/native: Add and use transactional KMS API This commit introduces, and makes use of, a transactional API used for setting up KMS state, later to be applied, potentially atomically. From an API point of view, so is always the case, but in the current implementation, it still uses legacy drmMode* API to apply the state non-atomically. The API consists of various buliding blocks: * MetaKmsUpdate - a set of configuration changes, the higher level handle for handing over configuration to the impl backend. It's used to set mode, assign framebuffers to planes, queue page flips and set connector properties. * MetaKmsPlaneAssignment - the assignment of a framebuffer to a plane. Currently used to map a framebuffer to the primary plane of a CRTC. In the legacy KMS implementation, the plane assignment is used to derive the framebuffer used for mode setting and page flipping. This also means various high level changes: State, excluding configuring the cursor plane and creating/destroying DRM framebuffer handles, are applied in the end of a clutter frame, in one go. From an API point of view, this is done atomically, but as mentioned, only the non-atomic implementation exists so far. From MetaRendererNative's point of view, a page flip now initially always succeeds; the handling of EBUSY errors are done asynchronously in the MetaKmsImpl backend (still by retrying at refresh rate, but postponing flip callbacks instead of manipulating the frame clock). Handling of falling back to mode setting instead of page flipping is notified after the fact by a more precise page flip feedback API. EGLStream based page flipping relies on the impl backend not being atomic, as the page flipping is done in the EGLStream backend (e.g. nvidia driver). It uses a 'custom' page flip queueing method, keeping the EGLStream logic inside meta-renderer-native.c. Page flip handling is moved to meta-kms-impl-device.c from meta-gpu-kms.c. It goes via an extra idle callback before reaching meta-renderer-native.c to make sure callbacks are invoked outside of the impl context. While dummy power save page flipping is kept in meta-renderer-native.c, the EBUSY handling is moved to meta-kms-impl-simple.c. Instead of freezing the frame clock, actual page flip callbacks are postponed until all EBUSY retries have either succeeded or failed due to some other error than EBUSY. This effectively inhibits new frames to be drawn, meaning we won't stall waiting on the file descriptor for pending page flips. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-04-04 16:36:41 -04:00
gboolean (* process_update) (MetaKmsImpl *impl,
MetaKmsUpdate *update,
GError **error);
void (* handle_page_flip_callback) (MetaKmsImpl *impl,
MetaKmsPageFlipData *page_flip_data);
void (* discard_pending_page_flips) (MetaKmsImpl *impl);
kms: Process impl idle callbacks before pre dispatch flush mode_set_fallback() schedules a call to mode_set_fallback_feedback_idle(), but it is possible for Mutter to repaint before the idle callbacks are dispatched. If that happens, mode_set_fallback_feedback_idle() does not get called before Mutter enters wait_for_pending_flips(), leading to a deadlock. Add the needed interfaces so that meta_kms_device_dispatch_sync() can flush all the implementation idle callbacks before it checks if any "events" are available. This prevents the deadlock by ensuring mode_set_fallback_feedback_idle() does get called before potentially waiting for actual DRM events. Presumably this call would not be needed if the implementation was running in its own thread, since it would eventually dispatch its idle callbacks before going to sleep polling on the DRM fd. This call might even be unnecessary overhead in that case, synchronizing with the implementation thread needlessly. But the thread does not exist yet, so this is needed for now. This is part 1 of 2 fixing a complete desktop freeze when drmModePageFlip() fails with EINVAL and the fallback to drmModeSetCrtc() succeeds but the success is not registered correctly as completed "flip". The freeze occurs under wait_for_pending_flips() which calls down into meta_kms_impl_device_dispatch() which ends up poll()'ing the DRM fd even though drmModeSetCrtc() will not produce a DRM event, hence the poll() never returns. The freeze was observed when hotplugging a DisplayLink dock for the first time on Ubuntu 19.10. CC stable: gnome-3-34 https://gitlab.gnome.org/GNOME/mutter/merge_requests/953
2019-11-29 05:50:30 -05:00
void (* dispatch_idle) (MetaKmsImpl *impl);
backends/native: Add basic KMS abstraction building blocks The intention with KMS abstraction is to hide away accessing the drm functions behind an API that allows us to have different kind of KMS implementations, including legacy non-atomic and atomic. The intention is also that the code interacting with the drm device should be able to be run in a different thread than the main thread. This means that we need to make sure that all drm*() API usage must only occur from within tasks that eventually can be run in the dedicated thread. The idea here is that MetaKms provides a outward facing API other places of mutter can use (e.g. MetaGpuKms and friends), while MetaKmsImpl is an internal implementation that only gets interacted with via "tasks" posted via the MetaKms object. These tasks will in the future potentially be run on the dedicated KMS thread. Initially, we don't create any new threads. Likewise, MetaKmsDevice is a outward facing representation of a KMS device, while MetaKmsImplDevice is the corresponding implementation, which only runs from within the MetaKmsImpl tasks. This commit only moves opening and closing the device to this new API, while leaking the fd outside of the impl enclosure, effectively making the isolation for drm*() calls pointless. This, however, is necessary to allow gradual porting of drm interaction, and eventually the file descriptor in MetaGpuKms will be removed. For now, it's harmless, since everything still run in the main thread. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-01-29 04:24:44 -05:00
};
MetaKms * meta_kms_impl_get_kms (MetaKmsImpl *impl);
backend/native: Add and use transactional KMS API This commit introduces, and makes use of, a transactional API used for setting up KMS state, later to be applied, potentially atomically. From an API point of view, so is always the case, but in the current implementation, it still uses legacy drmMode* API to apply the state non-atomically. The API consists of various buliding blocks: * MetaKmsUpdate - a set of configuration changes, the higher level handle for handing over configuration to the impl backend. It's used to set mode, assign framebuffers to planes, queue page flips and set connector properties. * MetaKmsPlaneAssignment - the assignment of a framebuffer to a plane. Currently used to map a framebuffer to the primary plane of a CRTC. In the legacy KMS implementation, the plane assignment is used to derive the framebuffer used for mode setting and page flipping. This also means various high level changes: State, excluding configuring the cursor plane and creating/destroying DRM framebuffer handles, are applied in the end of a clutter frame, in one go. From an API point of view, this is done atomically, but as mentioned, only the non-atomic implementation exists so far. From MetaRendererNative's point of view, a page flip now initially always succeeds; the handling of EBUSY errors are done asynchronously in the MetaKmsImpl backend (still by retrying at refresh rate, but postponing flip callbacks instead of manipulating the frame clock). Handling of falling back to mode setting instead of page flipping is notified after the fact by a more precise page flip feedback API. EGLStream based page flipping relies on the impl backend not being atomic, as the page flipping is done in the EGLStream backend (e.g. nvidia driver). It uses a 'custom' page flip queueing method, keeping the EGLStream logic inside meta-renderer-native.c. Page flip handling is moved to meta-kms-impl-device.c from meta-gpu-kms.c. It goes via an extra idle callback before reaching meta-renderer-native.c to make sure callbacks are invoked outside of the impl context. While dummy power save page flipping is kept in meta-renderer-native.c, the EBUSY handling is moved to meta-kms-impl-simple.c. Instead of freezing the frame clock, actual page flip callbacks are postponed until all EBUSY retries have either succeeded or failed due to some other error than EBUSY. This effectively inhibits new frames to be drawn, meaning we won't stall waiting on the file descriptor for pending page flips. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-04-04 16:36:41 -04:00
gboolean meta_kms_impl_process_update (MetaKmsImpl *impl,
MetaKmsUpdate *update,
GError **error);
void meta_kms_impl_handle_page_flip_callback (MetaKmsImpl *impl,
MetaKmsPageFlipData *page_flip_data);
void meta_kms_impl_discard_pending_page_flips (MetaKmsImpl *impl);
kms: Process impl idle callbacks before pre dispatch flush mode_set_fallback() schedules a call to mode_set_fallback_feedback_idle(), but it is possible for Mutter to repaint before the idle callbacks are dispatched. If that happens, mode_set_fallback_feedback_idle() does not get called before Mutter enters wait_for_pending_flips(), leading to a deadlock. Add the needed interfaces so that meta_kms_device_dispatch_sync() can flush all the implementation idle callbacks before it checks if any "events" are available. This prevents the deadlock by ensuring mode_set_fallback_feedback_idle() does get called before potentially waiting for actual DRM events. Presumably this call would not be needed if the implementation was running in its own thread, since it would eventually dispatch its idle callbacks before going to sleep polling on the DRM fd. This call might even be unnecessary overhead in that case, synchronizing with the implementation thread needlessly. But the thread does not exist yet, so this is needed for now. This is part 1 of 2 fixing a complete desktop freeze when drmModePageFlip() fails with EINVAL and the fallback to drmModeSetCrtc() succeeds but the success is not registered correctly as completed "flip". The freeze occurs under wait_for_pending_flips() which calls down into meta_kms_impl_device_dispatch() which ends up poll()'ing the DRM fd even though drmModeSetCrtc() will not produce a DRM event, hence the poll() never returns. The freeze was observed when hotplugging a DisplayLink dock for the first time on Ubuntu 19.10. CC stable: gnome-3-34 https://gitlab.gnome.org/GNOME/mutter/merge_requests/953
2019-11-29 05:50:30 -05:00
void meta_kms_impl_dispatch_idle (MetaKmsImpl *impl);
backends/native: Add basic KMS abstraction building blocks The intention with KMS abstraction is to hide away accessing the drm functions behind an API that allows us to have different kind of KMS implementations, including legacy non-atomic and atomic. The intention is also that the code interacting with the drm device should be able to be run in a different thread than the main thread. This means that we need to make sure that all drm*() API usage must only occur from within tasks that eventually can be run in the dedicated thread. The idea here is that MetaKms provides a outward facing API other places of mutter can use (e.g. MetaGpuKms and friends), while MetaKmsImpl is an internal implementation that only gets interacted with via "tasks" posted via the MetaKms object. These tasks will in the future potentially be run on the dedicated KMS thread. Initially, we don't create any new threads. Likewise, MetaKmsDevice is a outward facing representation of a KMS device, while MetaKmsImplDevice is the corresponding implementation, which only runs from within the MetaKmsImpl tasks. This commit only moves opening and closing the device to this new API, while leaking the fd outside of the impl enclosure, effectively making the isolation for drm*() calls pointless. This, however, is necessary to allow gradual porting of drm interaction, and eventually the file descriptor in MetaGpuKms will be removed. For now, it's harmless, since everything still run in the main thread. https://gitlab.gnome.org/GNOME/mutter/issues/548 https://gitlab.gnome.org/GNOME/mutter/merge_requests/525
2019-01-29 04:24:44 -05:00
#endif /* META_KMS_IMPL_H */