Re: missing madvise functionality

On Tue, Apr 03, 2007 at 10:20:02AM -0700, Ulrich Drepper wrote:
Andi Kleen wrote:
Why do you need a lock for that? I don't see any problem with
two threads doing that in parallel. The kernel would
serialize it internally and one would fail, but that shouldn't
be a problem.

There is no lock at all at userlevel. I'm talking about locks in the
kernel.

mmap_sem? Your new operation wouldn't solve that neither.

There were some proposals to fix mmap_sem (it's a big issue
for futexes too) but they're are quite involved.

-Andi
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