linux-kernel - Re: [RFC PATCH 0/3] Fix SLQB on memoryless configurations V2

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]

Date:	Tue, 22 Sep 2009 10:00:03 +1000
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	Mel Gorman <mel@....ul.ie>
Cc:	Nick Piggin <npiggin@...e.de>,
	Pekka Enberg <penberg@...helsinki.fi>,
	Christoph Lameter <cl@...ux-foundation.org>,
	heiko.carstens@...ibm.com, sachinp@...ibm.com,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	Tejun Heo <tj@...nel.org>
Subject: Re: [RFC PATCH 0/3] Fix SLQB on memoryless configurations V2

On Mon, 2009-09-21 at 17:10 +0100, Mel Gorman wrote:
> 
> It needs signed-off from the powerpc side because it's now allocating
> more
> memory potentially (Ben?). An alternative to this patch is in V1 that
> statically declares the per-node structures but this is potentially
> sub-optimal but from a performance and memory utilisation perspective.

So if I understand correctly, we have a problem with both cpu-less and
memory-less nodes. Interesting setups :-)

I have no strong objection on the allocating of the per-cpu data for
the cpu-less nodes. However, I wonder if we should do that a bit more
nicely, maybe with some kind of "adjusted" cpu_possible_mask() (could be
something like cpu_node_valid_mask or similar) to be used by percpu.

Mostly because it would be nice to have built-in debug features in
per-cpu and in that case, it would need some way to know a valid
number from an invalid one). Either that or just keep track of the
mask of cpus that had percpu data allocated to them

Cheers,
Ben.

--
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/