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

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Message-ID: <20160718103409.GH5783@n2100.arm.linux.org.uk>
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/
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