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From: "David S. Miller" <davem@redhat.com>
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Date: Mon, 6 Aug 2001 02:20:42 -0700 (PDT)
To: Andrea Arcangeli <andrea@suse.de>
Cc: David Luyer <david_luyer@pacific.net.au>, linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@transmeta.com>
Subject: Re: /proc/<n>/maps growing...
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Andrea Arcangeli writes:
 > Can somebody see a problem with this design?

As someone who was involved when the merge_segments stuff got tossed
by Linus, the reason was that the locking is utterly atrocious.

After trying to get the SMP locking correct _four_ times, Linus
basically said to me "This merging so stupidly complex, and we don't
need it at all.  We only need merging for very simple cases."

I think he's right.  The old code was trying to do everything and
made the locking more difficult than it needed to be.

Later,
David S. Miller
davem@redhat.com