702681 - Do not walk both ChunkSet and the internal chunk list

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Terrence Cole [:terrence]]

In DecommitFreePages we iterate over the runtime's ChunkSet and inside that walk over the list in the chunk info header.  The chunk set contains all chunks, so we can ignore the internal list.

Comment 1

[Terrence Cole [:terrence]]

Attachment: v1: trivail

https://tbpl.mozilla.org/?tree=Try&rev=62c1ce1bb4f5

Comment 2

[Igor Bukanov]

Comment on attachment 574622 [details] [diff] [review]
v1: trivail

Review of attachment 574622 [details] [diff] [review]:
-----------------------------------------------------------------

r+ with the comments addressed.

::: js/src/jsgc.cpp
@@ +2399,5 @@
>      JSRuntime *rt = cx->runtime;
>  
>      for (GCChunkSet::Range r(rt->gcChunkSet.all()); !r.empty(); r.popFront()) {
>          Chunk *chunk = r.front();
> +        ArenaHeader *aheader = static_cast<ArenaHeader*>(chunk->info.freeArenasHead);

Drop the cast  - freeArenasHead is ArenaHeader *

@@ +2421,3 @@
>              }
>  
> +            size_t arenaOffset = Chunk::arenaIndex(reinterpret_cast<uintptr_t>(aheader));

Call the variable arenaIndex for consistency with the rest of code and use aheader->arenaAddress(), not the cast here.

Comment 3

[Terrence Cole [:terrence]]

Attachment: v2: trivial

Comment 4

[Terrence Cole [:terrence]]

https://tbpl.mozilla.org/?tree=Mozilla-Inbound&rev=666ba50edd30

Comment 5

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/666ba50edd30