By delegating responsibility for shared surfaces reporting to imagelib,
we can cross reference the GPU shared surfaces cache with the local
surface cache in a content process (or the main process). This will
allow us to identify entries that are in the GPU cache but not in the
content/main process cache, and aid in debugging memory leaks. This
functionality is pref'd off by default behind image.mem.debug-reporting.
Additionally, we want to report every entry that was mapped into the
compositor process, in the compositor process memory report. This will
give us a sense of how much of our resident memory is consumed by mapped
images in absence of the more detailed cross referencing above.
At present, surface providers roll up all of their individual surfaces
into a single reporting unit. Specifically this means animated image
frames are all reported as a block. This patch removes that
consolidation and reports every frame as its own SurfaceMemoryReport.
This is important because each frame may have its own external image ID,
and we want to cross reference that with what we expect from the GPU
shared surfaces cache.
By delegating responsibility for shared surfaces reporting to imagelib,
we can cross reference the GPU shared surfaces cache with the local
surface cache in a content process (or the main process). This will
allow us to identify entries that are in the GPU cache but not in the
content/main process cache, and aid in debugging memory leaks. This
functionality is pref'd off by default behind image.mem.debug-reporting.
Additionally, we want to report every entry that was mapped into the
compositor process, in the compositor process memory report. This will
give us a sense of how much of our resident memory is consumed by mapped
images in absence of the more detailed cross referencing above.
At present, surface providers roll up all of their individual surfaces
into a single reporting unit. Specifically this means animated image
frames are all reported as a block. This patch removes that
consolidation and reports every frame as its own SurfaceMemoryReport.
This is important because each frame may have its own external image ID,
and we want to cross reference that with what we expect from the GPU
shared surfaces cache.
If FLAG_HIGH_QUALITY_SCALING is used, we should use
SurfaceCache::LookupBestMatch just like how it is done in RasterImage.
This may provide an alternative size at which we should rasterize the
SVG instead of the requested size. Since SurfaceCache imposes a maximum
size for which it will permit rasterized SVGs, we should also bypass the
cache entirely if we are well above that and simply draw directly to the
draw target in such cases.
With WebRender, it is somewhat more complicated. We will now return
NOT_SUPPORTED if the size is too big, and this should trigger fallback
to blob images. This should only produce drawing commands for the
relevant region and save us the high cost of rasterized a very large
surface on the main thread, which at the same time, looking as crisp as
a user would expect.
There is one main difference between raster images and vector images
with respect to factor of 2 scaling. Vector images may be scaled
infinitely and so we need to extend factor of 2 scaling to permit
growing instead of just shrinking. Also, we don't want to scale
infinitely, so we should configure a maximum size limit. This size limit
will apply even outside of factor of 2 scaling, and so the caller
(VectorImage) will need to be careful to take this into account.
If FLAG_HIGH_QUALITY_SCALING is used, we should use
SurfaceCache::LookupBestMatch just like how it is done in RasterImage.
This may provide an alternative size at which we should rasterize the
SVG instead of the requested size. Since SurfaceCache imposes a maximum
size for which it will permit rasterized SVGs, we should also bypass the
cache entirely if we are well above that and simply draw directly to the
draw target in such cases.
With WebRender, it is somewhat more complicated. We will now return
NOT_SUPPORTED if the size is too big, and this should trigger fallback
to blob images. This should only produce drawing commands for the
relevant region and save us the high cost of rasterized a very large
surface on the main thread, which at the same time, looking as crisp as
a user would expect.
There is one main difference between raster images and vector images
with respect to factor of 2 scaling. Vector images may be scaled
infinitely and so we need to extend factor of 2 scaling to permit
growing instead of just shrinking. Also, we don't want to scale
infinitely, so we should configure a maximum size limit. This size limit
will apply even outside of factor of 2 scaling, and so the caller
(VectorImage) will need to be careful to take this into account.
DecoderFlags::BLEND_ANIMATION will cause the decoder to inject the
BlendAnimationFilter from the previous patch into the SurfacePipe filter
chain. All frames produced by this decoder will be complete, and
should be equivalent to the result outputted by FrameAnimator.
This new SurfaceFilter can be added to a SurfacePipe to perform the
blending of a previous frame with the current partial frame, for an
animated image. This functionality is currently provided by
FrameAnimator and must be performed each time we want to advance the
displayed frame, all on the main thread. Moving this to SurfacePipe
allows us to do the same operation once per frame decode, and on a
decoder thread.
This should reduce the cost of a refresh tick since advancing animated
images is reduced to merely checking if the frame is available. Also, if
the image is below the discard frames threshold (to save memory), then
we will also save CPU due to only blending once at decode.
DecoderFlags::BLEND_ANIMATION will cause the decoder to inject the
BlendAnimationFilter from the previous patch into the SurfacePipe filter
chain. All frames produced by this decoder will be complete, and
should be equivalent to the result outputted by FrameAnimator.
This new SurfaceFilter can be added to a SurfacePipe to perform the
blending of a previous frame with the current partial frame, for an
animated image. This functionality is currently provided by
FrameAnimator and must be performed each time we want to advance the
displayed frame, all on the main thread. Moving this to SurfacePipe
allows us to do the same operation once per frame decode, and on a
decoder thread.
This should reduce the cost of a refresh tick since advancing animated
images is reduced to merely checking if the frame is available. Also, if
the image is below the discard frames threshold (to save memory), then
we will also save CPU due to only blending once at decode.
When generating display lists for WebRender, we were not caching the
draw result via nsDisplayItemGenericImageGeometry::UpdateDrawResult (or
similar) after completing CreateWebRenderCommands. This is important
because reftests use this to force sync decoding for images; it may be a
reason for image-related intermittent failures on *-qr builds.
Additionally, we may have been requesting fallback in cases where fallback
could not do anything more than WebRender could. For example, if we can't
get an image container yet, there is no point in requesting fallback
because it might just be we haven't started decoding yet. We should just
return the actual draw result in such cases.
In addition to the image container, the draw result can also be useful
for callers to know whether or not the surface(s) in the container are
fully decoded or not. This is used in subsequent parts to avoid
flickering in some cases.
nsIAssociatedContentSecurity and nsISecurityInfoProvider are unused as of
bug 832834, so this patch removes them.
Differential Revision: https://phabricator.services.mozilla.com/D5693
--HG--
extra : moz-landing-system : lando
The 'x' prefix makes it clearer that these are infallible.
A couple of nsJSID methods are now also infallible.
--HG--
extra : rebase_source : fcce44a00212d6d341afbf3827b31bd4f7355ad5
There are surprisingly many of them.
(Plus a couple of unnecessary checks after `new` calls that were nearby.)
--HG--
extra : rebase_source : 47b6d5d7c5c99b1b50b396daf7a3b67abfd74fc1
In addition to the image container, the draw result can also be useful
for callers to know whether or not the surface(s) in the container are
fully decoded or not. This is used in subsequent parts to avoid
flickering in some cases.
Timothy Nikkel
Andrew Osmond
Narcis Beleuzu
Andreea Pavel
Ehsan Akhgari
Coroiu Cristina
Noemi Erli
Dana Keeler
Jonathan Watt
Daniel Varga
Sylvestre Ledru
Jeff Muizelaar
Emilio Cobos Álvarez
Nicholas Nethercote
Cosmin Sabou