On Sun, 30 Jan 2005 23:10:02 +1100 Paul Mackerras <[EMAIL PROTECTED]> wrote:
> Andi Kleen writes: > > > I plan to fix this anyways in a more generic way - 4 level currently > > has some bad performance regression because it scans much more pagetables. > > DaveM had an old patch to use bitmaps for used entries in struct page. > > For your 32bit processes only the first bit would be set and it would not > > look at most of the pgds. The plan was to redo Dave's old patch > > for 4 level (I wanted to redo it a bit because I didn't like how > > his iterators worked) > > Sounds good. I'm looking forward to the patch. > > In the meantime I think that MM_VM_SIZE(mm) should be renamed to > MAX_TASK_SIZE without the mm argument. MAX_TASK_SIZE can default to > TASK_SIZE and be overridden on architectures that have more than one > task size. I'm looking forward very much to Andi's work as well. However, I like the mm->max_addr idea because that could be used for the mmap()/munmap()/mremap() sanity checks as well instead of bogus TASK_SIZE. There are some compat syscalls for the mmap like stuff that exists only to validate the address ranges for compat task limits.
