Maintain pre-zygote fork linear-alloc pages as shared-clean
Userfaultfd tends to dirty all the pages of the space it is used on.
However, we want to maintain the shared-clean trait of the pages
allocated in zygote process prior to first fork.
This CL separates the pre-zygote fork arenas from the userfaultfd
visited ones, thereby reataining the former's shared-clean trait.
Conflicts: Removed GetStartupLinearAlloc() usage which creeped in but is
not defined on this branch.
Bug: 160737021
Test: module install and enable uffd GC
Change-Id: Iddffb2c8d2d234ce7b20c069d86341dda5443a9b
(cherry picked from commit 49f034785005e53ca51d2af7985e41e4be3d802d)
Merged-In: Iddffb2c8d2d234ce7b20c069d86341dda5443a9b
10 files changed