linux-kernel - Re: [PATCH 10/27] mm, vmscan: Clear congestion, dirty and need for compaction on a per-node basis

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: <20160616102904.GH1868@techsingularity.net>
Date:	Thu, 16 Jun 2016 11:29:04 +0100
From:	Mel Gorman <mgorman@...hsingularity.net>
To:	Vlastimil Babka <vbabka@...e.cz>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Linux-MM <linux-mm@...ck.org>, Rik van Riel <riel@...riel.com>,
	Johannes Weiner <hannes@...xchg.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 10/27] mm, vmscan: Clear congestion, dirty and need for
 compaction on a per-node basis

On Thu, Jun 16, 2016 at 11:29:00AM +0200, Vlastimil Babka wrote:
> On 06/09/2016 08:04 PM, Mel Gorman wrote:
> >Congested and dirty tracking of a node and whether reclaim should stall
> >is still based on zone activity. This patch considers whether the kernel
> >should stall based on node-based reclaim activity.
> 
> I'm a bit confused about the description vs actual code.
> It appears to move some duplicated code to a related function, which is
> fine. The rest of callsites that didn't perform the clearing before
> (prepare_kswapd_sleep() and wakeup_kswapd()) might be a bit overkill, but
> won't hurt. But I don't see the part "considers whether the kernel
> should stall based on node-based reclaim activity". Is something missing?
> 

Tired when writing the changelog. Does this make more sense?

    mm, vmscan: Remove duplicate logic clearing node congestion and dirty state

    Reclaim may stall if there is too much dirty or congested data on a node.
    This was previously based on zone flags and the logic for clearing the
    flags is in two places. As congestion/dirty tracking is now tracked on
    a per-node basis, we can remove some duplicate logic.

-- 
Mel Gorman
SUSE Labs