SkOnceFlag is now statically initializable on all platforms.
Also adds sk_atomic_cas, used to implement new SkSpinlock.
Going to punt on making SkOnceFlag any smaller (for now, it's 8 bytes). We could conceivably get it down to two bits, one for done and one for a one-bit spinlock (we'd need atomic-& and atomic-| to make that work, but they appear to be available everywhere).
BUG=skia:1929
R=bungeman@google.com, reed@google.com
Author: mtklein@google.com
Review URL: https://codereview.chromium.org/123093002
git-svn-id: http://skia.googlecode.com/svn/trunk@12968 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
This patch removes static initializers related to static and
global mutexes from the final library's machine code when
building on a pthread-capable system.
We use PTHREAD_MUTEX_INITIALIZER to perform POD-style
initialization. You need a line like the following to declare
a global mutex with it:
SkBaseMutex gMutex = { PTHREAD_MUTEX_INITIALIZER };
We introduce the SK_DECLARE_STATIC_MUTEX and SK_DECLARE_GLOBAL_MUTEX
macros to be able to declare static/global mutexes in the source tree
uniformly.
SkMutex is now defined as a sub-class of SkBaseMutex, with standard
construction/destruction semantics. This is useful if the mutex
object is a member of another C++ class, or allocated dynamically.
We also modify a few places to refer to SkBaseMutex instead of a
SkMutex, where it makes sense. Generally speaking, client code
should hold and use pointers to SkBaseMutex whenever they can
now.
We defined a new built-time macro named SK_USE_POSIX_THREADS
to indicate that we're using a pthread-based SkThread.h
interface. The macro will also be used in future patches
to implement other helper thread synchronization classes.
Finally, we inline the acquire() and release() functions in the
case of Posix to improve performance a bit.
Running: 'bench -repeat 10 -match mutex' on an Android device or
a 2.4GHz Xeon Linux desktop shows the following improvements:
Before After
Galaxy Nexus 1.64 1.45
Nexus S 1.47 1.16
Xoom 1.86 1.66
Xeon 0.36 0.31
This removes 5 static mutex initializers from the library
Review URL: https://codereview.appspot.com/5501066
git-svn-id: http://skia.googlecode.com/svn/trunk@3091 2bbb7eff-a529-9590-31e7-b0007b416f81
I have manually examined all of these diffs and restored a few files that
seem to require manual adjustment.
The following files still need to be modified manually, in a separate CL:
android_sample/SampleApp/AndroidManifest.xml
android_sample/SampleApp/res/layout/layout.xml
android_sample/SampleApp/res/menu/sample.xml
android_sample/SampleApp/res/values/strings.xml
android_sample/SampleApp/src/com/skia/sampleapp/SampleApp.java
android_sample/SampleApp/src/com/skia/sampleapp/SampleView.java
experimental/CiCarbonSampleMain.c
experimental/CocoaDebugger/main.m
experimental/FileReaderApp/main.m
experimental/SimpleCocoaApp/main.m
experimental/iOSSampleApp/Shared/SkAlertPrompt.h
experimental/iOSSampleApp/Shared/SkAlertPrompt.m
experimental/iOSSampleApp/SkiOSSampleApp-Base.xcconfig
experimental/iOSSampleApp/SkiOSSampleApp-Debug.xcconfig
experimental/iOSSampleApp/SkiOSSampleApp-Release.xcconfig
gpu/src/android/GrGLDefaultInterface_android.cpp
gyp/common.gypi
gyp_skia
include/ports/SkHarfBuzzFont.h
include/views/SkOSWindow_wxwidgets.h
make.bat
make.py
src/opts/memset.arm.S
src/opts/memset16_neon.S
src/opts/memset32_neon.S
src/opts/opts_check_arm.cpp
src/ports/SkDebug_brew.cpp
src/ports/SkMemory_brew.cpp
src/ports/SkOSFile_brew.cpp
src/ports/SkXMLParser_empty.cpp
src/utils/ios/SkImageDecoder_iOS.mm
src/utils/ios/SkOSFile_iOS.mm
src/utils/ios/SkStream_NSData.mm
tests/FillPathTest.cpp
Review URL: http://codereview.appspot.com/4816058
git-svn-id: http://skia.googlecode.com/svn/trunk@1982 2bbb7eff-a529-9590-31e7-b0007b416f81
