[webkit-changes] [WebKit/WebKit] 91adc5: Postpone initialization of StructureAlignedMemoryA...

[Basuke Suzuki]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 91adc5e2412ce1d92a3271e5bc983618cb2aabba
      https://github.com/WebKit/WebKit/commit/91adc5e2412ce1d92a3271e5bc983618cb2aabba
  Author: Basuke Suzuki <basuke.suzuki at sony.com>
  Date:   2023-10-21 (Sat, 21 Oct 2023)

  Changed paths:
    M Source/JavaScriptCore/heap/StructureAlignedMemoryAllocator.cpp
    M Source/JavaScriptCore/runtime/InitializeThreading.cpp

  Log Message:
  -----------
  Postpone initialization of StructureAlignedMemoryAllocator.
https://bugs.webkit.org/show_bug.cgi?id=263380

Reviewed by Keith Miller.

StructureAlignedMemoryAllocator reserves a large amount of pages at startup
even on UIProcess and NetworkProcess because the initialization is called from
JSC::initialize().

In this patch, we postpone the initialization of StructureAlignedMemoryAllocator
until the first time it is used. Because permanentlyFreeze() will be called
at the end of construction of VM, it is safe to postpone the initialization.

* Source/JavaScriptCore/heap/StructureAlignedMemoryAllocator.cpp:
(JSC::StructureAlignedMemoryAllocator::tryMallocBlock):
* Source/JavaScriptCore/runtime/InitializeThreading.cpp:
(JSC::initialize):

Canonical link: https://commits.webkit.org/269633@main