Every doc I've found about using Android's atomics says, "stop".
"* A handful of basic atomic operations. The appropriate pthread
* functions should be used instead of these whenever possible."
"... we recommend stopping from using these functions entirely. Very fortunately, GCC provides handy intrinsics functions that work with very reasonable performance and always provide a full barrier."
As far as I can tell, there's no code generation change here: both the __sync atomics and the android_ atomics use full memory barriers. (And now with this all unified, it'll be easier to get the real wins by switching everything to __atomic atomics, which are like __sync atomics but allow control over memory barriers.)
BUG=skia:
R=bungeman@google.com, djsollen@google.com, mtklein@google.com, reed@google.com
Author: mtklein@chromium.org
Review URL: https://codereview.chromium.org/305593002
git-svn-id: http://skia.googlecode.com/svn/trunk@14896 2bbb7eff-a529-9590-31e7-b0007b416f81
Motivation:
I have downloaded a barebones Linux system built for 64-bit ARM
from linaro.org and a ARMv8 Foundation Model from arm.com to run
it on. This will let us build and test Skia on ARM64 before we
aquire hardware to allow that. This CL introduces the changes to
the build files necessary to build Skia on a barebones embedded
Linux system. I tested it with the aarch64 GCC compiler provided
by linaro.org.
Changes:
Add a "barelinux" target_os for the DEPS file. Add an optional
git download of zlib.
Changes to gyp files: these changes abstract out libpng, libz, and
giflib so that images.gyp doesn't know whether they are static or
dynamically linked. I also add the variables skia_giflib_static,
skia_libpng_static, skia_zlib_static, and skia_freetype_static,
all of which default to false but when set to true will override
the behavior of the giflib, libpng, zlib, and freetype build
targets to require them to build statically. Also, the
skia_no_fontconfig variable turns off use of the fontconfig service.
Scripts in platform_tools/barelinux/bin:
arm64_download - this script downloads the Linaro's ARMv8 Aarch64
toolchain and minimal embedded Linux system as well as ARM's
foundation model. The required files are mirrored on Google
Cloud. The script then starts a emulated Arm64 Linux system in
the background. After the boot is complete, you can SSH into the
system at port 8022 via user@localhost. The SSH key will be
downloaded into the working directery as well.
download_deps - Uses gclient to download Skia's dependencies for a
bare Linux system (the normal dependecies plus giflib, libpng, and
zlib.)
barelinux_make - this script builds a version of skia that does
not depend on external libraries, perfect for putting in an
embedded system running Linux. Assumes you have run download_deps
first.
To test:
To build a barelinux target, use the barelinux_make script.
To build for a armv8 system: skia_arch_type=arm arm_neon=0 armv7=1
armv8=1 arm_thumb=0 skia_arch_width=64 and set the CC and CXX
variables to point at the cross-compiler downloaded by
arm64_download.
R=djsollen@google.com, scroggo@google.com, borenet@google.com
Author: halcanary@google.com
Review URL: https://codereview.chromium.org/152513007
git-svn-id: http://skia.googlecode.com/svn/trunk@13570 2bbb7eff-a529-9590-31e7-b0007b416f81
Skia cannot use Chromium's implementation of mutex (Lock) due to static
initializers. However, we would like to be able to use Chromium's
implementation of atomics. This motivates the split of implementation.
Skia's atomic and mutex calls should be inlinable, especially the atomics.
These calls often compile down to very few instructions, and we currently have
the overhead of a function call. This motivates the header implementation.
There is still a desire for the build system to select the implementation, so
the SK_XXX_PLATFORM_H pattern for header files is introduced. This allows the
build system to control which platform specific header files are chosen.
The Chromium side changes (most of which will need to go in before this change
can be found at https://codereview.chromium.org/19477005/ .
The Chromium side changes after this lands can be seen at
https://codereview.chromium.org/98073013 .
Review URL: https://codereview.chromium.org/19808007
git-svn-id: http://skia.googlecode.com/svn/trunk@12738 2bbb7eff-a529-9590-31e7-b0007b416f81
- Implement ashmem-backed SkDiscardableMemory subclass:
This class in only accesible via the SkDiscardableMemory::Create()
function, which replaces the mock implementation in
SkDiscardableMemory_none.cpp
- Added SkDiscardableMemory_ashmem.cpp to the Android port of Skia
Removed SkDiscardableMemory_none.cpp from the Android port.
- Added DiscardableMemoryTest.
Still needs work.
- SkDiscardablePixelRef Bugfix:
onLockPixels() now calls SkDELETE on the SkDiscardableMemory pointer
when it fails to unlock.
- Improved documentation inside ashmem.h
BUG=
R=scroggo@google.com
Review URL: https://codereview.chromium.org/83563002
git-svn-id: http://skia.googlecode.com/svn/trunk@12608 2bbb7eff-a529-9590-31e7-b0007b416f81
This is a step toward targets declaring their deps in a sane fashion.
This change resolves cycles by forcing core to the root, then everything
in skia_lib pointing toward core as best possible, then everything
outside skia_lib depending on skia_lib for things in skia_lib. This
prevents double definitions where a symbol is provided by both the
skia_lib shared object and and a statically linked component of skia_lib.
R=djsollen@google.com
Review URL: https://codereview.chromium.org/19823003
git-svn-id: http://skia.googlecode.com/svn/trunk@10231 2bbb7eff-a529-9590-31e7-b0007b416f81
Need to avoid linking in .a things which are already provided by .so things.
git-svn-id: http://skia.googlecode.com/svn/trunk@10222 2bbb7eff-a529-9590-31e7-b0007b416f81
This is a step toward targets declaring their deps in a sane fashion.
This change resolves cycles by forcing core to the root,
then opts, ports, and utils depending on core, then everything else.
We will need some other change to resolve the fact that
core, opts, ports, and utils depend on each other and other targets which
depend on them. Outside of these targets, things look ok.
R=djsollen@google.com
Review URL: https://codereview.chromium.org/19823003
git-svn-id: http://skia.googlecode.com/svn/trunk@10217 2bbb7eff-a529-9590-31e7-b0007b416f81
SkTLS has it's own header separate from SkThread, and having SkThread own
the platform implementation of SkTLS is problematic with Chromium. The
simplest way to clean this up is to put the implementation in its own set
of files, where it is also more easily found.
R=robertphillips@google.com
Review URL: https://codereview.chromium.org/19240007
git-svn-id: http://skia.googlecode.com/svn/trunk@10105 2bbb7eff-a529-9590-31e7-b0007b416f81
SkPurgeableImageCache:
New image cache that uses virtual memory to store the pixels. Combines
features of SkAshmemImageCache (which has been removed) with SkPurgeableMemoryBlock, which has android and Mac versions.
SkImageCache:
Modified the API. pinCache now returns a status out parameter which
states whether the pinned memory retained the old data. This allows
allocAndPinCache to only be used for allocations.
Add a new debug only interface to purge unpinned data.
Updates to documentation, clarifying behavior.
Changed CachedStatus to MemoryStatus
SkLruImageCache:
Implement the new function purgeAllUnpinnedCaches and change implementation
of pinCache for the new behavior.
SkLazyPixelRef:
Rewrite onLockPixels to account for the new behavior of pinCache.
BitmapFactoryTest:
Test the new SkPurgeableImageCache.
Write tests which directly test the SkImageCaches.
Create a larger bitmap, since some of the SkImageCaches are designed
to handle large bitmaps.
bench_ and render_pictures:
Consolidate lazy_decode_bitmap into one function.
Allow using a flag to specify using the purgeable image cache.
Clean up some #includes.
Review URL: https://codereview.chromium.org/12433020
git-svn-id: http://skia.googlecode.com/svn/trunk@8207 2bbb7eff-a529-9590-31e7-b0007b416f81
