From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Mon, 20 Jan 2014 13:28:29 +0000 Subject: [PATCH] dma: fix vchan_cookie_complete() debug print In-Reply-To: <20140120120301.GE26823@intel.com> References: <1386344529-25617-1-git-send-email-jonas.jensen@gmail.com> <20140120095917.GZ26823@intel.com> <20140120112822.GA15937@n2100.arm.linux.org.uk> <20140120120301.GE26823@intel.com> Message-ID: <20140120132829.GD15937@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Jan 20, 2014 at 05:33:01PM +0530, Vinod Koul wrote: > On Mon, Jan 20, 2014 at 11:28:22AM +0000, Russell King - ARM Linux wrote: > > On Mon, Jan 20, 2014 at 03:29:17PM +0530, Vinod Koul wrote: > > > On Fri, Dec 06, 2013 at 04:42:09PM +0100, Jonas Jensen wrote: > > > > vd->tx.cookie is set zero on dma_cookie_complete(), > > > > save to local before printing it. > > > > > > > > Signed-off-by: Jonas Jensen > > > > --- > > > > > > > > Notes: > > > > dev_vdbg() could also be moved to happen earlier, what do you prefer? > > > This would be preferred IMHO. Also pls cc dmaengine at vger on this > > > > I prefer this version - it means that the verbose debug printk doesn't > > impact the completion timing when printk is expensive (eg, because its > > outputting via a serial port.) > But if you know your printk is costly, do you want to enable these? dev_vdbg() is for verbose debugging - you only enable it if you really need to. Even so, it should have _minimal_ impact where possible. That's why I prefer the first patch, because we mark the cookie as being complete _before_ we call the verbose debugging, which isn't going to add milliseconds to that. If you don't care about debugging, then getting rid of the dev_vdbg(). But really, I could pull rank and say that this is *my* file, I get to choose how stuff should be done here - I'd prefer not to but... -- FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up. Estimation in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad. Estimate before purchase was "up to 13.2Mbit".