linux-kernel - Re: [PATCH -mm] throttle direct reclaim when too many pages are isolated already (v3)

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: <20090715210253.bc137b2d.akpm@linux-foundation.org>
Date:	Wed, 15 Jul 2009 21:02:53 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Rik van Riel <riel@...hat.com>
Cc:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	LKML <linux-kernel@...r.kernel.org>,
	linux-mm <linux-mm@...ck.org>,
	Wu Fengguang <fengguang.wu@...el.com>
Subject: Re: [PATCH -mm] throttle direct reclaim when too many pages are
 isolated already (v3)

On Wed, 15 Jul 2009 23:53:18 -0400 Rik van Riel <riel@...hat.com> wrote:

> @@ -1049,6 +1074,14 @@ static unsigned long shrink_inactive_lis
>  	struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
>  	int lumpy_reclaim = 0;
>  
> +	while (unlikely(too_many_isolated(zone, file, sc))) {
> +		congestion_wait(WRITE, HZ/10);
> +
> +		/* We are about to die and free our memory. Return now. */
> +		if (fatal_signal_pending(current))
> +			return SWAP_CLUSTER_MAX;
> +	}

mutter.

While I agree that handling fatal signals on the direct reclaim path
is probably a good thing, this seems like a fairly random place at
which to start the enhancement.

If we were to step back and approach this in a broader fashion, perhaps
we would find some commonality with the existing TIF_MEMDIE handling,
dunno.


And I question the testedness of v3 :)
--
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/