This is not yet needed because we let active jobs be killed during by
the reset and we don't really bother making sure they can be restarted.
But once we start adding soft-stop support, controlling when we deal
with the remaining interrrupts and making sure those are handled before
the reset is issued gets tricky if we keep job interrupts active.
Let's prepare for that and mask+flush job IRQs before issuing a reset.
v4:
* Add a comment explaining why we WARN_ON(!job) in the irq handler
* Keep taking the job_lock when evicting stalled jobs
v3:
* New patch
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-11-boris.brezillon@collabora.com
Now that we can pass our own workqueue to drm_sched_init(), we can use
an ordered workqueue on for both the scheduler timeout tdr and our own
reset work (which we use when the reset is not caused by a fault/timeout
on a specific job, like when we have AS_ACTIVE bit stuck). This
guarantees that the timeout handlers and reset handler can't run
concurrently which drastically simplifies the locking.
v5:
* Don't call cancel_delayed_timeout() in the reset path (those works
are canceled in drm_sched_stop())
v4:
* Actually pass the reset workqueue to drm_sched_init()
* Don't call cancel_work_sync() in panfrost_reset(). It will deadlock
since it might be called from the reset work, which is executing and
cancel_work_sync() will wait for the handler to return. Checking the
reset pending status should avoid spurious resets
v3:
* New patch
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-10-boris.brezillon@collabora.com
This should avoid switching to interrupt context when the GPU is under
heavy use.
v3:
* Don't take the job_lock in panfrost_job_handle_irq()
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-9-boris.brezillon@collabora.com
Do the exception -> string translation using a table. This way we get
rid of those magic numbers and can easily add new fields if we need
to attach extra information to exception types.
v4:
* Don't expose exception type to userspace
* Merge the enum definition and the enum -> string table declaration
in the same patch
v3:
* Drop the error field
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-7-boris.brezillon@collabora.com
If the fence creation fail, we can return the error pointer directly.
The core will update the fence error accordingly.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-4-boris.brezillon@collabora.com
Mali Midgard/Bifrost GPUs have 3 hardware queues but only a global GPU
reset. This leads to extra complexity when we need to synchronize timeout
works with the reset work. One solution to address that is to have an
ordered workqueue at the driver level that will be used by the different
schedulers to queue their timeout work. Thanks to the serialization
provided by the ordered workqueue we are guaranteed that timeout
handlers are executed sequentially, and can thus easily reset the GPU
from the timeout handler without extra synchronization.
v5:
* Add a new paragraph to the timedout_job() method
v3:
* New patch
v4:
* Actually use the timeout_wq to queue the timeout work
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Christian König <christian.koenig@amd.com>
Cc: Qiang Yu <yuq825@gmail.com>
Cc: Emma Anholt <emma@anholt.net>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-3-boris.brezillon@collabora.com
The documentation is a bit vague and doesn't really describe what the
->timedout_job() is expected to do. Let's add a few more details.
v5:
* New patch
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210630062751.2832545-2-boris.brezillon@collabora.com
radeon_ttm_bo_destroy() is attempting to access the resource object to
update memory counters. However, the resource object is already freed when
ttm calls this function via the destroy callback. This causes an oops when
a bo is freed:
BUG: kernel NULL pointer dereference, address: 0000000000000010
RIP: 0010:radeon_ttm_bo_destroy+0x2c/0x100 [radeon]
Call Trace:
radeon_bo_unref+0x1a/0x30 [radeon]
radeon_gem_object_free+0x33/0x50 [radeon]
drm_gem_object_release_handle+0x69/0x70 [drm]
drm_gem_handle_delete+0x62/0xa0 [drm]
? drm_mode_destroy_dumb+0x40/0x40 [drm]
drm_ioctl_kernel+0xb2/0xf0 [drm]
drm_ioctl+0x30a/0x3c0 [drm]
? drm_mode_destroy_dumb+0x40/0x40 [drm]
radeon_drm_ioctl+0x49/0x80 [radeon]
__x64_sys_ioctl+0x8e/0xd0
Avoid the issue by updating the counters in the delete_mem_notify callback
instead. Also, fix memory statistic updating in radeon_bo_move() to
identify the source type correctly. The source type needs to be saved
before the move, because the moved from object may be altered by the move.
Fixes: bfa3357ef9 ("drm/ttm: allocate resource object instead of embedding it v2")
Signed-off-by: Mikel Rychliski <mikel@mikelr.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624045121.15643-1-mikel@mikelr.com
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in zte.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-28-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in xlnx.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-27-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in vmxgfx. All usage of
the field within vmwgfx can safely be removed.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-26-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in vkms.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Melissa Wen <melissa.srw@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-25-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in vc4.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-24-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't use it in tidss.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-23-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in tegra.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-22-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in sun4i.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-21-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in stm.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Yannick Fertre <yannick.fertre@foss.st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-20-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in sti.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-19-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in rockchip.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-18-tzimmermann@suse.de
Replace usage of struct drm_device.irq_enabled with the driver's
own state field struct omap_drm_device.irq_enabled. The field in
the DRM device structure is considered legacy and should not be
used by KMS drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-16-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in nouveau.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-15-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in mediatek.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-14-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in dcss.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Laurentiu Palcu <laurentiu.palcu@oss.nxp.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-13-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in imx.
v3:
* move dcss changes into separate patch (Laurentiu)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-12-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in kirin.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-11-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in exynos.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-10-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in malidp.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-9-tzimmermann@suse.de
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in komeda.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-8-tzimmermann@suse.de
Replace usage of struct drm_device.irq_enabled with the driver's
own state field struct drm_i915_private.irq_enabled. The field in
the DRM device structure is considered legacy and should not be
used by KMS drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-7-tzimmermann@suse.de
For KMS drivers, replace the IRQ check in VBLANK ioctls with a check for
vblank support. IRQs might be enabled wthout vblanking being supported.
This change also removes the DRM framework's only dependency on IRQ state
for non-legacy drivers. For legacy drivers with userspace modesetting,
the original test remains in drm_wait_vblank_ioctl().
v4:
* avoid preprocessor ifdef in drm_wait_vblank_ioctl()
(Jani, Thierry)
v3:
* optimize test in drm_wait_vblank_ioctl() for KMS case (Liviu)
* update docs for drm_irq_uninstall()
v2:
* keep the old test for legacy drivers in
drm_wait_vblank_ioctl() (Daniel)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-5-tzimmermann@suse.de
Replace usage of struct drm_device.irq_enabled with the driver's
own state field struct radeon_device.irq.installed. The field in
the DRM device structure is considered legacy and should not be
used by KMS drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-4-tzimmermann@suse.de
Remove the check around drm_irq_uninstall(). The same test is
done by the function internally. The tested state in irq_enabled
is considered obsolete and should not be used by KMS drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-3-tzimmermann@suse.de
Replace usage of struct drm_device.irq_enabled with the driver's
own state field struct amdgpu_device.irq.installed. The field in
the DRM device structure is considered legacy and should not be
used by KMS drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-2-tzimmermann@suse.de
The panfrost driver tries to kill in-flight jobs on FD close after
destroying the FD scheduler entities. For this to work properly, we
need to make sure the jobs popped from the scheduler entities have
been queued at the HW level before declaring the entity idle, otherwise
we might iterate over a list that doesn't contain those jobs.
Suggested-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624140850.2229697-1-boris.brezillon@collabora.com
Goes through all the drivers and deletes the default hook since it's
the default now.
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Andrew Jeffery <andrew@aj.id.au>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Emma Anholt <emma@anholt.net>
Cc: David Lechner <david@lechnology.com>
Cc: Kamlesh Gurudasani <kamlesh.gurudasani@gmail.com>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-aspeed@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210622165511.3169559-14-daniel.vetter@ffwll.ch
It's tedious to review this all the time, and my audit showed that
arcpgu actually forgot to set this.
Make this the default and stop worrying.
Again I sprinkled WARN_ON_ONCE on top to make sure we don't have
strange combinations of hooks: cleanup_fb without prepare_fb doesn't
make sense, and since simpler drivers are all new they better be GEM
based drivers.
v2: Warn and bail when it's _not_ a GEM driver (Noralf)
v3: It's neither ... nor, not not (Sam)
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210623162456.3373469-1-daniel.vetter@ffwll.ch
I guess no one ever tried running omap together with lima or panfrost,
not even sure that's possible. Anyway for consistency, fix this.
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Tomi Valkeinen <tomba@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210622165511.3169559-12-daniel.vetter@ffwll.ch
Like we have for the shadow helpers too, and roll it out to drivers.
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Tian Tao <tiantao6@hisilicon.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210622165511.3169559-11-daniel.vetter@ffwll.ch
All they do is refcount the fb, which the atomic helpers already do.
This is was necessary with the legacy helpers and I guess just carry
over in the conversion. drm_plane_state always has a full reference
for its ->fb pointer during its entire lifetime,
see __drm_atomic_helper_plane_destroy_state()
Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Russell King <linux@armlinux.org.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210622165511.3169559-10-daniel.vetter@ffwll.ch
There's a bunch of atomic drivers who don't do this quite correctly,
luckily most of them aren't in wide use or people would have noticed
the tearing.
By making this the default we avoid the constant audit pain and can
additionally remove a ton of lines from vfuncs for a bit more clarity
in smaller drivers.
While at it complain if there's a cleanup_fb hook but no prepare_fb
hook, because that makes no sense. I haven't found any driver which
violates this, but better safe than sorry.
Subsequent patches will reap the benefits.
v2: It's neither ... nor, not not (Sam)
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210623162200.3372056-1-daniel.vetter@ffwll.ch
Docs for struct dma_resv are fairly clear:
"A reservation object can have attached one exclusive fence (normally
associated with write operations) or N shared fences (read
operations)."
https://dri.freedesktop.org/docs/drm/driver-api/dma-buf.html#reservation-objects
Furthermore a review across all of upstream.
First of render drivers and how they set implicit fences:
- nouveau follows this contract, see in validate_fini_no_ticket()
nouveau_bo_fence(nvbo, fence, !!b->write_domains);
and that last boolean controls whether the exclusive or shared fence
slot is used.
- radeon follows this contract by setting
p->relocs[i].tv.num_shared = !r->write_domain;
in radeon_cs_parser_relocs(), which ensures that the call to
ttm_eu_fence_buffer_objects() in radeon_cs_parser_fini() will do the
right thing.
- vmwgfx seems to follow this contract with the shotgun approach of
always setting ttm_val_buf->num_shared = 0, which means
ttm_eu_fence_buffer_objects() will only use the exclusive slot.
- etnaviv follows this contract, as can be trivially seen by looking
at submit_attach_object_fences()
- i915 is a bit a convoluted maze with multiple paths leading to
i915_vma_move_to_active(). Which sets the exclusive flag if
EXEC_OBJECT_WRITE is set. This can either come as a buffer flag for
softpin mode, or through the write_domain when using relocations. It
follows this contract.
- lima follows this contract, see lima_gem_submit() which sets the
exclusive fence when the LIMA_SUBMIT_BO_WRITE flag is set for that
bo
- msm follows this contract, see msm_gpu_submit() which sets the
exclusive flag when the MSM_SUBMIT_BO_WRITE is set for that buffer
- panfrost follows this contract with the shotgun approach of just
always setting the exclusive fence, see
panfrost_attach_object_fences(). Benefits of a single engine I guess
- v3d follows this contract with the same shotgun approach in
v3d_attach_fences_and_unlock_reservation(), but it has at least an
XXX comment that maybe this should be improved
- v4c uses the same shotgun approach of always setting an exclusive
fence, see vc4_update_bo_seqnos()
- vgem also follows this contract, see vgem_fence_attach_ioctl() and
the VGEM_FENCE_WRITE. This is used in some igts to validate prime
sharing with i915.ko without the need of a 2nd gpu
- vritio follows this contract again with the shotgun approach of
always setting an exclusive fence, see virtio_gpu_array_add_fence()
This covers the setting of the exclusive fences when writing.
Synchronizing against the exclusive fence is a lot more tricky, and I
only spot checked a few:
- i915 does it, with the optional EXEC_OBJECT_ASYNC to skip all
implicit dependencies (which is used by vulkan)
- etnaviv does this. Implicit dependencies are collected in
submit_fence_sync(), again with an opt-out flag
ETNA_SUBMIT_NO_IMPLICIT. These are then picked up in
etnaviv_sched_dependency which is the
drm_sched_backend_ops->dependency callback.
- v4c seems to not do much here, maybe gets away with it by not having
a scheduler and only a single engine. Since all newer broadcom chips than
the OG vc4 use v3d for rendering, which follows this contract, the
impact of this issue is fairly small.
- v3d does this using the drm_gem_fence_array_add_implicit() helper,
which then it's drm_sched_backend_ops->dependency callback
v3d_job_dependency() picks up.
- panfrost is nice here and tracks the implicit fences in
panfrost_job->implicit_fences, which again the
drm_sched_backend_ops->dependency callback panfrost_job_dependency()
picks up. It is mildly questionable though since it only picks up
exclusive fences in panfrost_acquire_object_fences(), but not buggy
in practice because it also always sets the exclusive fence. It
should pick up both sets of fences, just in case there's ever going
to be a 2nd gpu in a SoC with a mali gpu. Or maybe a mali SoC with a
pcie port and a real gpu, which might actually happen eventually. A
bug, but easy to fix. Should probably use the
drm_gem_fence_array_add_implicit() helper.
- lima is nice an easy, uses drm_gem_fence_array_add_implicit() and
the same schema as v3d.
- msm is mildly entertaining. It also supports MSM_SUBMIT_NO_IMPLICIT,
but because it doesn't use the drm/scheduler it handles fences from
the wrong context with a synchronous dma_fence_wait. See
submit_fence_sync() leading to msm_gem_sync_object(). Investing into
a scheduler might be a good idea.
- all the remaining drivers are ttm based, where I hope they do
appropriately obey implicit fences already. I didn't do the full
audit there because a) not follow the contract would confuse ttm
quite well and b) reading non-standard scheduler and submit code
which isn't based on drm/scheduler is a pain.
Onwards to the display side.
- Any driver using the drm_gem_plane_helper_prepare_fb() helper will
correctly. Overwhelmingly most drivers get this right, except a few
totally dont. I'll follow up with a patch to make this the default
and avoid a bunch of bugs.
- I didn't audit the ttm drivers, but given that dma_resv started
there I hope they get this right.
In conclusion this IS the contract, both as documented and
overwhelmingly implemented, specically as implemented by all render
drivers except amdgpu.
Amdgpu tried to fix this already in
commit 049aca4363
Author: Christian König <christian.koenig@amd.com>
Date: Wed Sep 19 16:54:35 2018 +0200
drm/amdgpu: fix using shared fence for exported BOs v2
but this fix falls short on a number of areas:
- It's racy, by the time the buffer is shared it might be too late. To
make sure there's definitely never a problem we need to set the
fences correctly for any buffer that's potentially exportable.
- It's breaking uapi, dma-buf fds support poll() and differentitiate
between, which was introduced in
commit 9b495a5887
Author: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Date: Tue Jul 1 12:57:43 2014 +0200
dma-buf: add poll support, v3
- Christian König wants to nack new uapi building further on this
dma_resv contract because it breaks amdgpu, quoting
"Yeah, and that is exactly the reason why I will NAK this uAPI change.
"This doesn't works for amdgpu at all for the reasons outlined above."
https://lore.kernel.org/dri-devel/f2eb6751-2f82-9b23-f57e-548de5b729de@gmail.com/
Rejecting new development because your own driver is broken and
violates established cross driver contracts and uapi is really not
how upstream works.
Now this patch will have a severe performance impact on anything that
runs on multiple engines. So we can't just merge it outright, but need
a bit a plan:
- amdgpu needs a proper uapi for handling implicit fencing. The funny
thing is that to do it correctly, implicit fencing must be treated
as a very strange IPC mechanism for transporting fences, where both
setting the fence and dependency intercepts must be handled
explicitly. Current best practices is a per-bo flag to indicate
writes, and a per-bo flag to to skip implicit fencing in the CS
ioctl as a new chunk.
- Since amdgpu has been shipping with broken behaviour we need an
opt-out flag from the butchered implicit fencing model to enable the
proper explicit implicit fencing model.
- for kernel memory fences due to bo moves at least the i915 idea is
to use ttm_bo->moving. amdgpu probably needs the same.
- since the current p2p dma-buf interface assumes the kernel memory
fence is in the exclusive dma_resv fence slot we need to add a new
fence slot for kernel fences, which must never be ignored. Since
currently only amdgpu supports this there's no real problem here
yet, until amdgpu gains a NO_IMPLICIT CS flag.
- New userspace needs to ship in enough desktop distros so that users
wont notice the perf impact. I think we can ignore LTS distros who
upgrade their kernels but not their mesa3d snapshot.
- Then when this is all in place we can merge this patch here.
What is not a solution to this problem here is trying to make the
dma_resv rules in the kernel more clever. The fundamental issue here
is that the amdgpu CS uapi is the least expressive one across all
drivers (only equalled by panfrost, which has an actual excuse) by not
allowing any userspace control over how implicit sync is conducted.
Until this is fixed it's completely pointless to make the kernel more
clever to improve amdgpu, because all we're doing is papering over
this uapi design issue. amdgpu needs to attain the status quo
established by other drivers first, once that's achieved we can tackle
the remaining issues in a consistent way across drivers.
v2: Bas pointed me at AMDGPU_GEM_CREATE_EXPLICIT_SYNC, which I
entirely missed.
This is great because it means the amdgpu specific piece for proper
implicit fence handling exists already, and that since a while. The
only thing that's now missing is
- fishing the implicit fences out of a shared object at the right time
- setting the exclusive implicit fence slot at the right time.
Jason has a patch series to fill that gap with a bunch of generic
ioctl on the dma-buf fd:
https://lore.kernel.org/dri-devel/20210520190007.534046-1-jason@jlekstrand.net/
v3: Since Christian has fixed amdgpu now in
commit 8c505bdc9c (drm-misc/drm-misc-next)
Author: Christian König <christian.koenig@amd.com>
Date: Wed Jun 9 13:51:36 2021 +0200
drm/amdgpu: rework dma_resv handling v3
Use the audit covered in this commit message as the excuse to update
the dma-buf docs around dma_buf.resv usage across drivers.
Since dynamic importers have different rules also hammer these in
again while we're at it.
v4:
- Add the missing "through the device" in the dynamic section that I
overlooked.
- Fix a kerneldoc markup mistake, the link didn't connect
v5:
- A few s/should/must/ to make clear what must be done (if the driver
does implicit sync) and what's more a maybe (Daniel Stone)
- drop all the example api discussion, that needs to be expanded,
clarified and put into a new chapter in drm-uapi.rst (Daniel Stone)
Cc: Daniel Stone <daniel@fooishbar.org>
Acked-by: Daniel Stone <daniel@fooishbar.org>
Reviewed-by: Dave Airlie <airlied@redhat.com> (v4)
Reviewed-by: Christian König <christian.koenig@amd.com> (v3)
Cc: mesa-dev@lists.freedesktop.org
Cc: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Rob Clark <robdclark@chromium.org>
Cc: Kristian H. Kristensen <hoegsberg@google.com>
Cc: Michel Dänzer <michel@daenzer.net>
Cc: Daniel Stone <daniels@collabora.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Deepak R Varma <mh12gx2825@gmail.com>
Cc: Chen Li <chenli@uniontech.com>
Cc: Kevin Wang <kevin1.wang@amd.com>
Cc: Dennis Li <Dennis.Li@amd.com>
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624125246.166721-1-daniel.vetter@ffwll.ch
Also review & update everything while we're at it.
This is prep work to smash a ton of stuff into the kerneldoc for
@resv.
v2: Move the doc for sysfs_entry.attachment_uid to the right place too
(Sam)
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Christian König <christian.koenig@amd.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Nirmoy Das <nirmoy.das@amd.com>
Cc: Deepak R Varma <mh12gx2825@gmail.com>
Cc: Chen Li <chenli@uniontech.com>
Cc: Kevin Wang <kevin1.wang@amd.com>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210623161712.3370885-1-daniel.vetter@ffwll.ch
Spotted while trying to convert panfrost to these.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210622165511.3169559-15-daniel.vetter@ffwll.ch
