Now with ttm_buffer_object being a subclass of drm_gem_object we can
easily lookup ttm_buffer_object for a given drm_gem_object, which in
turn allows to create common helper functions.
This patch starts off with a drm_gem_ttm_print_info() helper function
which adds some ttm specific lines to the debug output.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20190904054740.20817-3-kraxel@redhat.com
Frequent mapping and unmapping a buffer object adds overhead for
modifying the page table and creates debug output. Unmapping a buffer
is only required when the memory manager evicts the buffer from its
current location.
v4:
* WARN_ON if buffer is still mapped during BO cleanup
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reported-and-tested-by: Davidlohr Bueso <dbueso@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20190906122056.32018-5-tzimmermann@suse.de
The implementation of vmap() is a combined pin() and kmap(). As both
functions share the same lock, we can make vmap() slightly faster by
acquiring the lock only once for both operations. Same for the inverse,
vunmap().
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reported-and-tested-by: Davidlohr Bueso <dbueso@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20190906122056.32018-3-tzimmermann@suse.de
The kmap and kunmap operations of GEM VRAM buffers can now be called
in interleaving pairs. The first call to drm_gem_vram_kmap() maps the
buffer's memory to kernel address space and the final call to
drm_gem_vram_kunmap() unmaps the memory. Intermediate calls to these
functions increment or decrement a reference counter.
This change allows for keeping buffer memory mapped for longer and
minimizes the amount of changes to TLB, page tables, etc.
v4:
* lock in kmap()/kunmap() with ttm_bo_reserve()
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reported-and-tested-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190906122056.32018-2-tzimmermann@suse.de
Use the new cec_notifier_cec_adap_(un)register() functions to
(un)register the notifier for the CEC adapter.
Signed-off-by: Dariusz Marcinkiewicz <darekm@google.com>
Tested-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Link: https://patchwork.freedesktop.org/patch/msgid/20190814104520.6001-5-darekm@google.com
Use the new cec_notifier_conn_(un)register() functions to
(un)register the notifier for the HDMI connector, and fill in
the cec_connector_info.
Changes since v7:
- err_runtime_disable -> err_rpm_disable
Changes since v2:
- removed unnecessary call to invalidate phys address before
deregistering the notifier,
- use cec_notifier_phys_addr_invalidate instead of setting
invalid address on a notifier.
Signed-off-by: Dariusz Marcinkiewicz <darekm@google.com>
Tested-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: use 'if (!hdata->notifier)' instead of '== NULL']
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Link: https://patchwork.freedesktop.org/patch/msgid/20190828123415.139441-1-darekm@google.com
Set the connector info for the CEC adapter. This helps
userspace to associate the CEC device with the HDMI connector.
Tested on a Cubieboard.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Tested-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823112427.42394-3-hverkuil-cisco@xs4all.nl
The implementation of functions encoder_enable and encoder_disable
make possible to control the pinctrl according to the encoder type.
The pinctrl must be activated only if the encoder type is DPI.
This helps to move the DPI-related pinctrl configuration from
all the panel or bridge to the LTDC dt node.
Reviewed-by: Philippe Cornu <philippe.cornu@st.com>
Signed-off-by: Yannick Fertré <yannick.fertre@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1567761708-31777-1-git-send-email-yannick.fertre@st.com
The drm panel bridge creates a connector using a connector type
explicitly passed by the display controller or bridge driver that
instantiates the panel bridge. Now that drm_panel reports its connector
type, we can use it to avoid passing an explicit (and often incorrect)
connector type to drm_panel_bridge_add() and
devm_drm_panel_bridge_add().
Several drivers report incorrect or unknown connector types to
userspace. Reporting a different type may result in a breakage. For that
reason, rename (devm_)drm_panel_bridge_add() to
(devm_)drm_panel_bridge_add_typed(), and add new
(devm_)drm_panel_bridge_add() functions that use the panel connector
type. Update all callers of (devm_)drm_panel_bridge_add() to the _typed
function, they will be converted one by one after testing.
The panel drivers have been updated with the following Coccinelle
semantic patch, with manual inspection and fixes to indentation.
@@
expression bridge;
expression dev;
expression panel;
identifier type;
@@
(
-bridge = drm_panel_bridge_add(panel, type);
+bridge = drm_panel_bridge_add_typed(panel, type);
|
-bridge = devm_drm_panel_bridge_add(dev, panel, type);
+bridge = devm_drm_panel_bridge_add_typed(dev, panel, type);
)
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190904132804.29680-3-laurent.pinchart@ideasonboard.com
Add a type field to the drm_panel structure to report the panel type,
using DRM_MODE_CONNECTOR_* macros (the values that make sense are LVDS,
eDP, DSI and DPI). This will be used to initialise the corresponding
connector type.
Update all panel drivers accordingly. The panel-simple driver only
specifies the type for the known to be LVDS panels, while all other
panels are left as unknown and will be converted on a case-by-case
basis as they all need to be carefully reviewed.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190904132804.29680-2-laurent.pinchart@ideasonboard.com
This function lost its only call site as part of
earlier dead code removal, so remove it as well:
drivers/video/fbdev/sa1100fb.c:975:21: error: unused function 'sa1100fb_min_dma_period' [-Werror,-Wunused-function]
Fixes: 390e5de112 ("fbdev/sa1100fb: Remove dead code")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190906151307.1127187-1-arnd@arndb.de
- it's what we recommend in our docs:
https://dri.freedesktop.org/docs/drm/gpu/drm-uapi.html#recommended-ioctl-return-values
- it's the overwhelmingly used error code for "operation not
supported", at least in drm core (slightly less so in drivers):
$ git grep EOPNOTSUPP -- drivers/gpu/drm/*c | wc -l
83
$ git grep ENOTSUPP -- drivers/gpu/drm/*c | wc -l
5
- include/linux/errno.h makes it fairly clear that these are for nfsv3
(plus they also have error codes above 512, which is the block with
some special behaviour ...)
/* Defined for the NFSv3 protocol */
If the above isn't reflecting current practice, then I guess we should
at least update the docs.
Noralf commented:
Ben Hutchings made this comment[1] in a thread about use of ENOTSUPP in
drivers:
glibc's strerror() returns these strings for ENOTSUPP and EOPNOTSUPP
respectively:
"Unknown error 524"
"Operation not supported"
So at least for errors returned to userspace EOPNOTSUPP makes sense.
José asked:
> Hopefully this will not break any userspace
None of the functions in drm_edid.c affected by this reach userspace,
it's all driver internal.
Same for the mipi function, that error code should be handled by
drivers. Drivers are supposed to remap "the hw is on fire" to EIO when
reporting up to userspace, but I think if a driver sees this it would
be a driver bug.
v2: Augment commit message with comments from Noralf and José
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Sean Paul <sean@poorly.run>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andres Rodriguez <andresx7@gmail.com>
Cc: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190904143942.31756-1-daniel.vetter@ffwll.ch
Move object release into a separate worker. Releasing objects requires
sending commands to the host. Doing that in the dequeue worker will
cause deadlocks in case the command queue gets filled up, because the
dequeue worker is also the one which will free up slots in the command
queue.
Reported-by: Chia-I Wu <olvaffe@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Tested-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190830060116.10476-1-kraxel@redhat.com
virtio-gpu basically needs a sg_table for the bo, to tell the host where
the backing pages for the object are. So the gem shmem helpers are a
perfect fit. Some drm_gem_object_funcs need thin wrappers to update the
host state, but otherwise the helpers handle everything just fine.
Once the fencing was sorted the switch was surprisingly easy and for the
most part just removing the ttm code.
v4: fix drm_gem_object_funcs name.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-15-kraxel@redhat.com
Rework fencing workflow. Stop using ttm helpers, use the
virtio_gpu_array_* helpers instead.
Due to using the gem reservation object it is initialized and ready for
use before calling ttm_bo_init. So we can simply use the standard
fencing workflow and drop the tricky logic which checks whenever the
command is in flight still.
v6: rewrite most of the patch.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-10-kraxel@redhat.com
Rework fencing workflow, starting with virtio_gpu_execbuffer_ioctl.
Stop using ttm helpers, use the virtio_gpu_array_* helpers (which work
on the reservation objects directly) instead.
Also store the object array in struct virtio_gpu_vbuffer, so we
explicitly keep a reference of all buffers used instead of depending
on ttm_bo_put() checking whenever the object is actually idle before
releasing it.
New workflow:
(1) All gem objects needed by a command are added to a
virtio_gpu_object_array.
(2) All reservation objects will be locked (virtio_gpu_array_lock_resv).
(3) virtio_gpu_fence_emit() completes fence initialization.
(4) fence gets added to the objects, reservation objects are unlocked
(virtio_gpu_array_add_fence, virtio_gpu_array_unlock_resv).
(5) virtio command is submitted to the host.
(6) The completion callback (virtio_gpu_dequeue_ctrl_func)
will drop object references and free virtio_gpu_object_array.
v6: rewrite most of the patch.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-9-kraxel@redhat.com
Some helper functions to manage an array of gem objects.
v9: use dma_resv_lock_interruptible.
v6:
- add ticket to struct virtio_gpu_object_array.
- add virtio_gpu_array_{lock,unlock}_resv helpers.
- add virtio_gpu_array_add_fence helper.
v5: some small optimizations (Chia-I Wu).
v4: make them virtio-private instead of generic helpers.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-8-kraxel@redhat.com
Use drm_gem_reservation_object_wait() in virtio_gpu_wait_ioctl().
This also makes the ioctl run lockless.
v9: fix return value.
v5: handle lookup failure.
v2: use reservation_object_test_signaled_rcu for VIRTGPU_WAIT_NOWAIT.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-3-kraxel@redhat.com
With this gem and ttm will use the same reservation object,
so mixing and matching ttm / gem reservation helpers should
work fine.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-2-kraxel@redhat.com
Declare local pointer to the drm_dp_link_address_ack_reply struct
instead of constantly dereferencing it through the union in
txmsg->reply. Then, invert the order of conditionals so we don't have to
do the bulk of the work inside them, and can wrap lines even less. Then
finally, rearrange variable declarations a bit.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-16-lyude@redhat.com
* Remove the big ugly have_eomt conditional
* Store &mgr->down_rep_recv.initial_hdr in a var to make line wrapping
easier
* Remove duplicate memset() calls
* Actually wrap lines
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-14-lyude@redhat.com
There's a couple of changes here, so to summarize:
* Remove the big ugly mgr->up_req_recv.have_eomt conditional to save on
indenting
* Store &mgr->up_req_recv.initial_hdr in a variable so we don't keep
going over 80 character long lines
* De-duplicate code for calling drm_dp_send_up_ack_reply() and getting
the MSTB via it's GUID
* Remove all of the duplicate calls to memset() and just use a goto
instead
* Actually do line wrapping
* Remove the unnecessary if (mstb) check before calling
drm_dp_mst_topology_put_mstb() - we are guaranteed to always have
mstb != NULL at that point in the function
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-13-lyude@redhat.com
And it's helper, we'll be using this in just a moment.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-12-lyude@redhat.com
Which reduces indentation and makes this function more legible.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-11-lyude@redhat.com
Use more pointers so we don't have to write out
txmsg->reply.u.path_resources each time. Also, fix line wrapping +
rearrange local variables.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-10-lyude@redhat.com
Unfortunately the DP MST helpers do not have much in the way of
debugging utilities. So, let's add some!
This adds basic debugging output for down sideband requests that we send
from the driver, so that we can actually discern what's happening when
sideband requests timeout.
Since there wasn't really a good way of testing that any of this worked,
I ended up writing simple selftests that lightly test sideband message
encoding and decoding as well. Enjoy!
Changes since v1:
* Clean up DO_TEST() and sideband_msg_req_encode_decode() - danvet
* Get rid of pr_fmt(), just define a prefix string instead and use
drm_printf()
* Check highest bit of VCPI in drm_dp_decode_sideband_req() - danvet
* Make the switch case order between drm_dp_decode_sideband_req() and
drm_dp_encode_sideband_req() the same - danvet
* Only check DRM_UT_DP - danvet
* Clean up sideband_msg_req_equal() from selftests a bit, and add
comments explaining why we can't just use memcmp - danvet
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-8-lyude@redhat.com
Noticed this while working on adding a drm_dp_decode_sideband_req().
DP_POWER_DOWN_PHY/DP_POWER_UP_PHY both use the same struct as
DP_ENUM_PATH_RESOURCES, so we can just combine their cases.
Changes since v2:
* Fix commit message
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903215702.16984-1-lyude@redhat.com
A simple convienence function that returns a drm_printer which prints
using pr_err()
Changes since v1:
* Make __drm_printfn_err() more consistent with DRM_ERROR() - danvet
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-6-lyude@redhat.com
Yes, apparently we've been testing this for every single driver load for
quite a long time now. At least that means our PBN calculation is solid!
Anyway, introduce self tests for MST and move this into there.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-5-lyude@redhat.com
This seems to be some leftover detritus from before the port/mstb kref
cleanup and doesn't do anything anymore, so get rid of it.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-3-lyude@redhat.com
Makes things easier to read.
Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-2-lyude@redhat.com
We can reduce the critical section in vkms_vblank_simulate under
output->lock quite a lot:
- hrtimer_forward_now just needs to be ordered correctly wrt
drm_crtc_handle_vblank. We already access the hrtimer timestamp
without locks. While auditing that I noticed that we don't correctly
annotate the read there, so sprinkle a READ_ONCE to make sure the
compiler doesn't do anything foolish.
- drm_crtc_handle_vblank must stay under the lock to avoid races with
drm_crtc_arm_vblank_event.
- The access to vkms_ouptut->crc_state also must stay under the lock.
- next problem is making sure the output->state structure doesn't get
freed too early. First we rely on a given hrtimer being serialized:
If we call drm_crtc_handle_vblank, then we are guaranteed that the
previous call to vkms_vblank_simulate has completed. The other side
of the coin is that the atomic updates waits for the vblank to
happen before it releases the old state. Both taken together means
that by the time the atomic update releases the old state, the
hrtimer won't access it anymore (it might be accessing the new state
at the same time, but that's ok).
- state is invariant, except the few fields separate protected by
state->crc_lock. So no need to hold the lock for that.
- finally the queue_work. We need to make sure there's no races with
the flush_work, i.e. when we call flush_work we need to guarantee
that the hrtimer can't requeue the work again. This is guaranteed by
the same vblank/hrtimer ordering guarantees like the reasoning above
why state won't be freed too early: flush_work on the old state is
called after wait_for_flip_done in the atomic commit code.
Therefore we can also move everything after the output->crc_state out
of the critical section.
Motivated by suggestions from Rodrigo.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190719152314.7706-3-daniel.vetter@ffwll.ch
