What we might reasonably choose to end up doing there (in 2.6.25)
is sending tmpfs etc. through the extra faulting for linked files,
but skipping it as at present for unlinked files i.e. shared memory
would continue to skip the extra faults, shared memory being the case we
really wanted to avoid the overhead on when dirty page accounting came in.
I care a bit, because I don't like to feel that tmpfs is now left
saddled with the bug that every filesystem has had for years before.
I'll need to compare the small performance cost of fixing it against
the unease of leaving it alone.
Hugh
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