highmem-2.4.7-A0 [Re: kmap() while holding spinlock]

[Ingo Molnar]

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> [...] or to do the clearing (and copying) speculatively, after
> allocating the page but before locking the pagetable lock. This might
> lead to a bit more work in the pagefault-race case, but we dont care
> about that window. It will on the other hand reduce pagetable_lock
> contention (because the clearing/copying is done outside the lock), so
> perhaps this solution is better.

the attached highmem-2.4.7-A0 patch implements this method in both
affected functions. Comments?

	Ingo

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