- It's no longer needed to help the (2011?) transition to SkAutoTUnref.
- It prevents us from making classes that go in SkAutoTUnrefs final,
i.e. all ref-counted classes.
This had better not have been public API...
TBR=reed@google.com
BUG=skia:
Review URL: https://codereview.chromium.org/1068443002
This adds sk_memory_barrier(), implemented using sk_atomic_fetch_add() on an uninitialized variable. If that becomes a problem we can drop this to the porting layer, using std::atomic_thread_fence() / __atomic_thread_fence() / __sync_synchronize().
The big win is that ref() doesn't generate a memory barrier any more on ARM.
This is an instance of SkSafeRef() in SkPaint(const SkPaint&) after this CL:
4d0: 684a ldr r2, [r1, #4]
4d2: 6018 str r0, [r3, #0]
4d4: b13a cbz r2, 4e6 <_ZN7SkPaintC1ERKS_+0x2e>
4d6: 1d10 adds r0, r2, #4
4d8: e850 4f00 ldrex r4, [r0]
4dc: 3401 adds r4, #1
4de: e840 4500 strex r5, r4, [r0]
4e2: 2d00 cmp r5, #0
4e4: d1f8 bne.n 4d8 <_ZN7SkPaintC1ERKS_+0x20>
Here's the before, pretty much the same with two memory barriers surrounding the ref():
4d8: 684a ldr r2, [r1, #4]
4da: 6018 str r0, [r3, #0]
4dc: b15a cbz r2, 4f6 <_ZN7SkPaintC1ERKS_+0x3e>
4de: 1d10 adds r0, r2, #4
4e0: f3bf 8f5f dmb sy
4e4: e850 4f00 ldrex r4, [r0]
4e8: 3401 adds r4, #1
4ea: e840 4500 strex r5, r4, [r0]
4ee: 2d00 cmp r5, #0
4f0: d1f8 bne.n 4e4 <_ZN7SkPaintC1ERKS_+0x2c>
4f2: f3bf 8f5f dmb sy
The miscellaneous files in here are just fixups to explicitly include SkMutex.h,
instead of leeching it off SkRefCnt.h.
No public API changes.
TBR=reed@google.com
Build trybots seem hosed.
NOTRY=true
BUG=skia:
Review URL: https://codereview.chromium.org/896803002
This code requires fewer macros to use it (just one), has less code in macro
definitions, and has simpler synchronization code (just atomic ints, no SkOnce,
no SkMutex, etc.)
A minor downside, we lose indentation and reverse-ordering in the final report:
Leaked SkRefCntBase: 7
Leaked SkFontMgr: 1
Leaked SkWeakRefCnt: 1
Leaked SkTypeface: 1
Leaked SkFlattenable: 3
Leaked SkXfermode: 3
Leaked SkPathRef: 1
Leaked SkPixelRef: 1
Leaked SkMallocPixelRef: 1
becomes
Leaked SkXfermode: 3
Leaked SkMallocPixelRef: 1
Leaked SkPixelRef: 1
Leaked SkPathRef: 1
Leaked SkFlattenable: 3
Leaked SkTypeface: 1
Leaked SkWeakRefCnt: 1
Leaked SkFontMgr: 1
Leaked SkRefCntBase: 7
This is motivated by wanting to land https://codereview.chromium.org/806473006/,
which makes sure all static use of SkOnce are in global scope. The current
implementation of SkInstCnt uses them in function scope, which isn't safe.
BUG=skia:
No public API changes.
TBR=reed@google.com
Review URL: https://codereview.chromium.org/841263004
SkNVRefCnt is a variant of SkRefCnt that's Not Virtual, so weighs 4 bytes
instead of 8 or 16. There's only benefit to doing this if the deriving class
does not otherwise need a vtable, e.g. SkPicture.
I've stripped out some cruft from SkPicture, rearranged fields to pack tightly,
and added compile asserts for the sizes of SkPicture, SkRecord, and
SkVarAlloc.
BUG=skia:3144
Review URL: https://codereview.chromium.org/741793002
When unique() returns true, it must also issue an acquire barrier.
Note that this change may adversly impact SkPath performance,
but editing SkPaths is already a performance issue.
BUG=chromium:258499
No API changes.
TBR=reed@google.com
Review URL: https://codereview.chromium.org/687293002
Example failure:
fRefCnt was 3
../../../usr/local/google/home/mtklein/skia/include/core/SkRefCnt.h:40: failed assertion "(fRefCnt == 1) || (SkDebugf("fRefCnt was %d""\n", fRefCnt), false)"
Command terminated by signal 11
Not pretty, but everything's there. Perhaps we'll think of ways to make it nicer later.
BUG=skia:
R=bsalomon@google.com, reed@google.com, mtklein@google.com
Author: mtklein@chromium.org
Review URL: https://codereview.chromium.org/337243004
This is mostly s/public SkNoncopyable/SkNoncopyable/g.
Two classes (SkDrawLooper::Context and SkPicture::OperationList) don't actually work with SkNoncopyable because they introduce a virtual destructor. I added SkNoncopyableVirtual to make them work as intended. Sort of questionable whether they really need to be noncopyable in the first place, but I guess it doesn't hurt to keep the behavior the same.
BUG=skia:
R=reed@google.com, mtklein@google.com
Author: mtklein@chromium.org
Review URL: https://codereview.chromium.org/226183018
git-svn-id: http://skia.googlecode.com/svn/trunk@14081 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
std::shared_ptr has a method called 'unique' which captures the concept that
a reference count of 1 is special, and can be used to optimize copy on write.
It also has some undocumented need for memory barriers in certain situations
and those needs are documented here.
The motivation for looking into this is crbug.com/258499 . The use of the
reference count in this manner is a benign race with both ref() and unref().
By introducing sk_atomic_unprotected_read, it is possible for Chromium to
annotate this read to tell ThreadSanitizer that this is known.
R=bsalomon@google.com
Review URL: https://codereview.chromium.org/18770007
git-svn-id: http://skia.googlecode.com/svn/trunk@10221 2bbb7eff-a529-9590-31e7-b0007b416f81
smart pointers without need for another smart pointer type.
Note that the semantics of SkRefCnt match those WTF expects. In
particular, newly created objects have refcount 1 and objects are
deallocated at refcount 0.
This seems like a better fit than the AddRef/Release alises which exist
for scoped_ptr (but seem unused).
BUG=254509
R=reed@google.com
Author: jbroman@chromium.org
Review URL: https://chromiumcodereview.appspot.com/17880003
git-svn-id: http://skia.googlecode.com/svn/trunk@9784 2bbb7eff-a529-9590-31e7-b0007b416f81
https://codereview.chromium.org/13925021/
If a non-POD class does not provide a default destructor, one is
provided by teh compiler. GCC will do so, but only at the point where the
vtable is output; since BlockRef has no implementation its destructor is
never output, so there is no complaint. VC++, however, provides the
destructor implementation as soon as it sees the type. If the destructor
of BlockRef is ever defined an error will be reported (since the
destructor of SkData is private).
Declaring (but does not defining) a destructor for BlockRef fixes two
issues. First, it prevents a default destructor from being provided,
removing the VC++ error. Second, BlockRef now blocks access to the
destructor through '->'.
git-svn-id: http://skia.googlecode.com/svn/trunk@8697 2bbb7eff-a529-9590-31e7-b0007b416f81
