Oilpan: Mark the NodeList hierarchy MainThreadOnly

Oilpan: Mark the NodeList hierarchy MainThreadOnly

The NodeList hierarchy is accessed only by the main thread.
Given that NodeList is performance-sensitive in various benchmarks in blink_perf,
this CL explicitly marks the NodeList hierarchy MainThreadOnly.

BUG=420515
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=183721

[haraken, 2014-10-12 15:23:00]

haraken@chromium.org changed reviewers:
+ oilpan-reviews@chromium.org

[haraken, 2014-10-12 15:23:01]

PTAL

[haraken, 2014-10-15 01:12:56]

keishi-san: would you take a look at this?

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
File Source/platform/heap/ThreadState.h (right):

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
Source/platform/heap/ThreadState.h:89: // indicates that classes in T's
hierarchy are used only by the main thread.

I'm planning to address the FIXME by introducing GarbageCollectedOnMainThread in
a follow-up.

[tkent, 2014-10-15 03:34:38]

tkent@chromium.org changed reviewers:
+ tkent@chromium.org

[tkent, 2014-10-15 03:34:39]

lgtm

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
File Source/platform/heap/ThreadState.h (right):

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
Source/platform/heap/ThreadState.h:89: // indicates that classes in T's
hierarchy are used only by the main thread.
On 2014/10/15 01:12:56, haraken wrote:
> 
> I'm planning to address the FIXME by introducing GarbageCollectedOnMainThread
in
> a follow-up.

The GarbageCollectedOnMainThread approach sounds good.

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
Source/platform/heap/ThreadState.h:94: bool derivesNode =
WTF::IsSubclass<typename WTF::RemoveConst<T>::Type, Node>::value
Now derivesNode is a wrong name.  It will be removed soon because of
GarbageCollectedOnMainThread, right?

[haraken, 2014-10-15 03:38:59]

Thanks for review.

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
File Source/platform/heap/ThreadState.h (right):

https://codereview.chromium.org/646833003/diff/1/Source/platform/heap/ThreadS...
Source/platform/heap/ThreadState.h:94: bool derivesNode =
WTF::IsSubclass<typename WTF::RemoveConst<T>::Type, Node>::value
On 2014/10/15 03:34:39, tkent wrote:
> Now derivesNode is a wrong name.  It will be removed soon because of
> GarbageCollectedOnMainThread, right?

Renamed it to mainThreadOnly.

[haraken, 2014-10-15 03:39:02]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2014-10-15 03:39:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/646833003/50001

[commit-bot: I haz the power, 2014-10-15 05:59:26]

Committed patchset #2 (id:50001) as 183721