linux-kernel - Re: [PATCH 2/7] dmaengine: omap-dma: Complete the cookie first on transfer completion

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:	Mon, 18 Jul 2016 11:34:10 +0100
From:	Russell King - ARM Linux <linux@...linux.org.uk>
To:	Peter Ujfalusi <peter.ujfalusi@...com>
Cc:	vinod.koul@...el.com, linux-kernel@...r.kernel.org,
	dmaengine@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	linux-omap@...r.kernel.org, tony@...mide.com
Subject: Re: [PATCH 2/7] dmaengine: omap-dma: Complete the cookie first on
 transfer completion

On Thu, Jul 14, 2016 at 03:42:37PM +0300, Peter Ujfalusi wrote:
> Before looking for the next descriptor to start, complete the just finished
> cookie.

This change will reduce performance as we no longer have an overlap
between the next request starting to be dealt with in the hardware
vs the previous request being completed.  Your commit log doesn't
say _why_ the change is being made, it merely tells us what the
patch is doing, which we can see already.

Please describe changes a little better.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.