This syscall avoids the need to guess an unused filename in /dev/shm and
allows seals to be placed on it. We immediately return if no fd got
returned, as there isn’t anything we can do otherwise.
Seals especially allow the compositor to drop the SIGBUS protections,
since the kernel promises the fd won’t ever shrink.
This removes support for any platform but Linux from this vo.
vo_wayland was removed during the wayland rewrite done in 0.28. However,
it is still useful for systems that do not have OpenGL.
The new wayland_common code makes vo_wayland much simpler, and
eliminates many of the issues the previous vo_wayland had.
2 years ago, ANGLE removed the old NV12-specific extension, and added
a new one that supports a number of formats, including P010. Actually
they just renamed it and removed their initial annoying and obvious
design error (bravo, Google).
Since it broke 2 years ago, nobody should give a shit about this code,
and it should just be removed. But for some reason I still dived the
shit-tank (Windows development).
I guess Intel code monkeys can't write drivers (or maybe the issue is
because we're doing zero-copy, which probably maybe is not actually
allowed by D3D11 due to array textures, see --d3d11va-zero-copy), so
the P010 path is completely untested. It doesn't work, I'll delete all
this ANGLE hwdec code.
Fixes: #7054
Query information on the system output most linked to the swap chain,
and either utilize a user-configured format, or either 8bit
RGBA or 10bit RGB with 2bit alpha depending on the system output's
bit depth.
The old way of using wayland in mpv relied on an external renderloop for
semi-accurate timings. This had multiple issues though. Display sync
would break whenever the window was hidden (since the frame callback
stopped being executed) which was really annoying. Also the entire
external renderloop logic was kind of fragile and didn't play well with
mpv's internal structure (i.e. using presentation time in that old
paradigm breaks stats.lua).
Basically the problem is that swap buffers blocks on wayland which is
crap whenever you hide the mpv window since it looks up the entire
player. So you have to make swap buffers not block, but this has a
different problem. Timings will be terrible if you use the unblocked
swap buffers call.
Based on some discussion in #wayland, the trick here is relatively
simple and works well enough for our purposes. Instead we basically
build a way to block with a timeout in the wayland buffer swap
functions.
A bool is set in the frame callback function that indicates whether or
not mpv is waiting for a frame to be displayed. In the actual buffer
swap function, we enter into a while loop waiting for this flag to be
set. At the same time, the wl_display is polled to block the thread and
wakeup if it receives any events from the compositor. This loop only
breaks if enough time has passed or if the frame callback bool is
received.
In the near future, it is better to set whether or not frame a frame has
been displayed in the presentation feedback. However as a first pass,
doing it in the frame callback is more than good enough.
The "downside" is that we render frames that aren't actually shown on
screen when the player is hidden (it seems like wayland people don't
like that). But who cares. Accurate timings are way more important. It's
probably not too hard to add that behavior back in the player though.
The externally driven renderloop was originally added for the wayland
context (to make display sync somewhat work), but it has a lot of issues
with mpv's internal structure. A different approach should be used.
This reverts commit a743fef837.
This affects hwdec_dxva2dxgi, which uses ra_d3d11_wrap_tex to wrap RGB
video frames that are shared with a D3D9 device. Without it, mpv uses
nearest instead of bilinear scaling with --scale=bilinear (the default)
and --hwdec=dxva2. It's kind of hard to believe this bug has gone
unnoticed for almost two years, but that seems to have been the case.
Fixes: #7042
all the get_property_* usages were removed because in some circumstances
they can lead to deadlocks. they were replaced by accessing the vo and
mp_vo_opts structs directly, like on other vos.
additionally the mpv helper was split into a mpv and libmpv helper, to
differentiate between private and public APIs and for future changes
like a macOS vulkan context for vo=gpu.
This is the proper fix to the memory leak @wm4 pointed out. It turns out
that when you autoprobe opengl and vo_wayland_init returns false,
vo_wayland_uninit is never actually executed. So you have a leftover
pointer. The vulkan context does this correctly which was why my old,
dumb "fix" broke it.
Dumb idea. The correct thing to do is to fix the preinit and context
creation so that the uninit is correctly executed when probing fails
(and then everything gets freed).
This reverts commit defc8f359c.
wm4 mentioned that the wayland autoprobe leaked. A simple oversight in
the wayland_common code forgot to free the vo_wayland_state if
vo_wayland_init returned false.
I previously skipped creating the wl_output if the --fullscreen flag
with no --fsscreen_id was inputted, so the fullscreen video lands on the
correct output (where mpv was launched). This has breakage if someone
combines the --autofit flag (or other similar options with it). Instead,
just actually read xdg_shell spec and realize that you can pass NULL to
xdg_toplevel_set_fullscreen and let the compositor choose the output if
the user doesn't specify it. If this has issues, get a better
compositor.
Normalize nullptr and an empty string both to nullptr to simplify
handling. API users cannot set a value back to nullptr, so both
an empty string as well as nullptr should behave the same.
Turns out clearing all frambuffers in reconfig isn't such a great idea
when you also end up here when setting pan/scan.
I guess this is just a leftover from a previous iteration of vo_drm
where doing this made sense.
Previously, there appeared to be implicit synchronisation in the
GL interop path, and we never observed any visual glitches. However,
recently, I started seeing stuttering in the GL path and on closer
examination it looked like read-before-write behaviour where GL
would display an old frame again rather than the current one.
After verifying that disabling hwdec made the problem go away,
I tried adding a cuStreamSynchronize() after the memcpys and that
also resolved the problem, so it's clearly sync related.
cuStreamSynchronize() is a CPU sync and so more heavy-weight than
you want, but it's the only tool we have. There is no mechanism
defined for synchronising GL to CUDA (It looks like there is a way
to synchronise CUDA to EGL but it appears one way and so wouldn't
directly address this problem).
Anyway, empirically, the output now looks the same as with hwdec
off.
Swapchain depth currently hard-coded to 3 (4 buffers).
As we now avoid redrawing on repeat frames (we simply requeue the same fb
again), this should give a nice performance boost when playing videos with a
lower FPS than the display FPS in video-sync=display-resample mode.
Presentation feedback has also been implemented to help counter the
significant amounts of jitter we would otherwise be seeing.
This allows to use drm hwaccels that require a hwdevice.
Tested with v4l2request hwaccel and cedrus driver on an allwinner device
running mpv with --vo=gpu --gpu-context=drm --hwdec=drm.
At first, this code used only 1 plane, so the compatibility stuff was
sufficient. But then use of planes 1 and 2 was added, without extending
the compatibility stuff.
I think I've seen a case recently where this broke the build and caused
users to apply invalid fixes, but I don't remember where.
It's possible that I didn't get all defines that are needed.
I think I was wrong about having to reset the stats when mpv stops
producing frames, eg. when it's paused. As long as the swapchain doesn't
underflow, last_queue_display_time will still be accurate, because the
next frame produced should still be presented one vsync after the
last one in the swapchain.
If the swapchain underflows (which is the common case for when mpv is
paused for more than 150ms,) the next predicted frame time should be in
the past. It should be fine to leave last_queue_display_time unset in
this case, since vo.c will use the current time instead, which is a
decent guess (though it doesn't take vsync phase into account.)
last_sync_refresh_count and last_sync_qpc_time should be kept on
swapchain underflow as well. Assuming the display refresh rate doesn't
change while mpv is paused, they'll only provide a more accurate guess
of the vsync duration when mpv starts playing again. Also,
vsync_duration_qpc never needs to get reset. It will get overwritten
immediately in most cases, and when it doesn't, it's still a better
guess of the vsync duration than nothing.
The render API (vo_libmpv) had potential deadlock problems with
MPV_RENDER_PARAM_ADVANCED_CONTROL. This required vd-lavc-dr to be
enabled (the default). I never observed these deadlocks in the wild
(doesn't mean they didn't happen), although I could specifically provoke
them with some code changes.
The problem was mostly about DR (direct rendering, letting the video
decoder write to OpenGL buffer memory). Allocating/freeing a DR image
needs to be done on the OpenGL thread, even though _lots_ of threads are
involved with handling images. Freeing a DR image is a special case that
can happen any time. dr_helper.c does most of the evil magic of
achieving this. Unfortunately, there was a (sort of) circular lock
dependency: freeing an image while certain internal locks are held would
trigger the user's context update callback, which in turn would call
mpv_render_context_update(), which processed all pending free requests,
and then acquire an internal lock - which the caller might not release
until a further DR image could be freed.
"Solve" this by making freeing DR images asynchronous. This is slightly
risky, but actually not much. The DR images will be free'd eventually.
The biggest disadvantage is probably that debugging might get trickier.
Any solution to this problem will probably add images to free to some
sort of queue, and then process it later. I considered making this more
explicit (so there'd be a point where the caller forcibly waits for all
queued items to be free'd), but discarded these ideas as this probably
would only increase complexity.
Another consequence is that freeing DR images on the GL thread is not
synchronous anymore. Instead, it mpv_render_context_update() will do it
with a delay. This seems roundabout, but doesn't actually change
anything, and avoids additional code.
This also fixes that the render API required the render API user to
remain on the same thread, even though this wasn't documented. As such,
it was a bug. OpenGL essentially forces you to do all GL usage on a
single thread, but in theory the API user could for example move the GL
context to another thread.
The API bump is because I think you can't make enough noise about this.
Since we don't backport fixes to old versions, I'm specifically stating
that old versions are broken, and I'm supplying workarounds.
Internally, dr_helper_create() does not use pthread_self() anymore, thus
the vo.c change. I think it's better to make binding to the current
thread as explicit as possible.
Of course it's not sure that this fixes all deadlocks (probably not).
This adds vsync reporting to the D3D11 backend using the presentation
feedback provided by DXGI, which is pretty similar to what's provided by
GLX_OML_sync_control in the GLX backend. In DirectX, PresentCount is the
SBC, PresentRefreshCount and SyncRefreshCount are kind of like the MSC
and SyncQPCTime is the UST.
Unlike GLX, the DXGI API makes it possible for PresentCount and
SyncQPCTime to refer to different physical vsyncs, in which case
PresentRefreshCount and SyncRefreshCount will be different. The code
supports this possibility, even though it's not clear whether it can
happen when using flip-model presentation. The docs say for flip-model
apps, PresentRefreshCount is equal to SyncRefreshCount "when the app
presents on every vsync," but on my hardware, they're always equal, even
when mpv misses a vsync. They can definitely be different in exclusive
fullscreen bitblt mode, though, which mpv doesn't support now, but might
support in future.
Another difference to GLX is that, at least on my hardware,
PresentRefreshCount and SyncRefreshCount always refer to the last
physical vsync on which mpv presented a frame, but glxGetSyncValues can
apparently return a MSC and UST from the most recent physical vsync,
even if mpv didn't present a new frame on it. This might result in
different behaviour between the two backends after dropped frames or
brief pauses.
Also note, the docs for the DXGI presentation feedback APIs are pretty
awful, even by Microsoft standards. In particular the docs for
DXGI_FRAME_STATISTICS are misleading (PresentCount really is the number
of times Present() has been called for that frame, not "the running
total count of times that an image was presented to the monitor since
the computer booted.")
For good documentation, try these:
https://docs.microsoft.com/en-us/windows/win32/direct3ddxgi/dxgi-flip-modelhttps://docs.microsoft.com/en-us/windows/win32/direct3d9/d3dpresentstatshttps://docs.microsoft.com/en-us/windows-hardware/drivers/ddi/content/d3dkmthk/ns-d3dkmthk-_d3dkmt_present_stats
(Yeah, the docs for the D3D9Ex and even the kernel-mode version of this
structure are better than the DXGI ones. It seems possible that they're
all rewordings of the same internal Microsoft docs, but whoever wrote
the DXGI one didn't really understand it.)
Certain mpv config options require wl->current_output to be created
before the video can actually start rendering. Just always create it
here if the current_output doesn't exist (the one exception being the
--fs option with no --fs-screen flag). Incidentally, this also fixes
--fs-screen not working on wayland.
