linux-kernel - Re: [patch 1/2] ufd v1 - unsequential O(1) fdmap core

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20070603230859.5000424d.akpm@linux-foundation.org>
Date:	Sun, 3 Jun 2007 23:08:59 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Davide Libenzi <davidel@...ilserver.org>
Cc:	Eric Dumazet <dada1@...mosbay.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Ulrich Drepper <drepper@...hat.com>,
	Ingo Molnar <mingo@...e.hu>
Subject: Re: [patch 1/2] ufd v1 - unsequential O(1) fdmap core

On Sun, 3 Jun 2007 15:51:13 -0700 (PDT) Davide Libenzi <davidel@...ilserver.org> wrote:

> A bitmap allocator made sense because it has the property of making 
> allocations compact. Once that requirement is relaxed, it does not make 
> any sense to use it (and you have still to modify it in any case).
> I generally agree on code re-use, but that just not the right structure. 
> You can tweak it how much you like, but you're still doing a search inside 
> an N-sized bitmap. It's just the *wrong* structure.

I must say that it's not really clear to me why this fdmap thing was
created.  Exactly what problem is it solving, and what properties is it
designed to have?

Could not a (prehaps suitably modified) IDR tree have adequately provided
those properties?

I'm sure it's good stuff, but the patches were presented as if we all know
what they're for.  But I don't.  Maybe I was asleep at the time.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/