linux-kernel - Re: [PATCH 4/7] Memory compaction 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: <87iqbeykx9.fsf@basil.nowhere.org>
Date:	Wed, 06 Jan 2010 22:37:22 +0100
From:	Andi Kleen <andi@...stfloor.org>
To:	Mel Gorman <mel@....ul.ie>
Cc:	Andrea Arcangeli <aarcange@...hat.com>,
	Christoph Lameter <cl@...ux-foundation.org>,
	Adam Litke <agl@...ibm.com>, Avi Kivity <avi@...hat.com>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [PATCH 4/7] Memory compaction core

Mel Gorman <mel@....ul.ie> writes:


Haven't reviewed the full thing, but one thing I noticed below:

> +
> +	/*
> +	 * Isolate free pages until enough are available to migrate the
> +	 * pages on cc->migratepages. We stop searching if the migrate
> +	 * and free page scanners meet or enough free pages are isolated.
> +	 */
> +	spin_lock_irq(&zone->lock);

Won't that cause very long lock hold times on large zones?
Presumably you need some kind of lock break heuristic.

-Andi

-- 
ak@...ux.intel.com -- Speaking for myself only.
--
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/