From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from skprod2.natinst.com ([130.164.80.23]:40825 "EHLO ni.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1422680AbbENWps (ORCPT ); Thu, 14 May 2015 18:45:48 -0400 Message-ID: <55552570.5050407@ni.com> Date: Thu, 14 May 2015 17:45:04 -0500 From: Xander Huff MIME-Version: 1.0 To: Sebastian Andrzej Siewior CC: jic23@kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, michal.simek@xilinx.com, soren.brinkmann@xilinx.com, linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rt-users@vger.kernel.org, ben.shelton@ni.com, joe.hershberger@ni.com, joshc@ni.com Subject: Re: [PATCH] iio: adc: xilinx-xadc: Convert to raw spinlock References: <1431013090-18996-1-git-send-email-xander.huff@ni.com> <20150514171038.GG13442@linutronix.de> In-Reply-To: <20150514171038.GG13442@linutronix.de> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 5/14/2015 12:10 PM, Sebastian Andrzej Siewior wrote: > > Do you have any cyclictest numbers how much the latency increases on > heavy iio usage? Traditionally the primary handler should be very quick > / short. > > Sebastian > With no other processes running, I got the following results after a couple of hours on one of our devices: admin@Xander-roboRIO:~# cyclictest -S -m -p 98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 0.01 0.07 0.12 1/176 1473 T: 0 ( 1373) P:98 I:1000 C:6503872 Min: 9 Act: 13 Avg: 13 Max: 51 T: 1 ( 1374) P:98 I:1500 C:4335914 Min: 9 Act: 12 Avg: 13 Max: 49 With a VI reading all default handles (raw, offset, scale, sampling_frequency) in /sys/bus/iio/devices/iio:device0 constantly in a while loop, I got the following results after a couple hours on the same device: admin@Xander-roboRIO:~# cyclictest -S -m -p 98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 6.93 7.30 7.47 3/182 1530 T: 0 ( 1487) P:98 I:1000 C:4497008 Min: 11 Act: 20 Avg: 21 Max: 69 T: 1 ( 1488) P:98 I:1500 C:2998005 Min: 11 Act: 20 Avg: 22 Max: 59 -- Xander Huff Staff Software Engineer National Instruments From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xander Huff Subject: Re: [PATCH] iio: adc: xilinx-xadc: Convert to raw spinlock Date: Thu, 14 May 2015 17:45:04 -0500 Message-ID: <55552570.5050407@ni.com> References: <1431013090-18996-1-git-send-email-xander.huff@ni.com> <20150514171038.GG13442@linutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, knaack.h-Mmb7MZpHnFY@public.gmane.org, lars-Qo5EllUWu/uELgA04lAiVw@public.gmane.org, pmeerw-jW+XmwGofnusTnJN9+BGXg@public.gmane.org, michal.simek-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, soren.brinkmann-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-rt-users-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ben.shelton-acOepvfBmUk@public.gmane.org, joe.hershberger-acOepvfBmUk@public.gmane.org, joshc-acOepvfBmUk@public.gmane.org To: Sebastian Andrzej Siewior Return-path: In-Reply-To: <20150514171038.GG13442-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org> Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rt-users.vger.kernel.org On 5/14/2015 12:10 PM, Sebastian Andrzej Siewior wrote: > > Do you have any cyclictest numbers how much the latency increases on > heavy iio usage? Traditionally the primary handler should be very quick > / short. > > Sebastian > With no other processes running, I got the following results after a couple of hours on one of our devices: admin@Xander-roboRIO:~# cyclictest -S -m -p 98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 0.01 0.07 0.12 1/176 1473 T: 0 ( 1373) P:98 I:1000 C:6503872 Min: 9 Act: 13 Avg: 13 Max: 51 T: 1 ( 1374) P:98 I:1500 C:4335914 Min: 9 Act: 12 Avg: 13 Max: 49 With a VI reading all default handles (raw, offset, scale, sampling_frequency) in /sys/bus/iio/devices/iio:device0 constantly in a while loop, I got the following results after a couple hours on the same device: admin@Xander-roboRIO:~# cyclictest -S -m -p 98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 6.93 7.30 7.47 3/182 1530 T: 0 ( 1487) P:98 I:1000 C:4497008 Min: 11 Act: 20 Avg: 21 Max: 69 T: 1 ( 1488) P:98 I:1500 C:2998005 Min: 11 Act: 20 Avg: 22 Max: 59 -- Xander Huff Staff Software Engineer National Instruments From mboxrd@z Thu Jan 1 00:00:00 1970 From: xander.huff@ni.com (Xander Huff) Date: Thu, 14 May 2015 17:45:04 -0500 Subject: [PATCH] iio: adc: xilinx-xadc: Convert to raw spinlock In-Reply-To: <20150514171038.GG13442@linutronix.de> References: <1431013090-18996-1-git-send-email-xander.huff@ni.com> <20150514171038.GG13442@linutronix.de> Message-ID: <55552570.5050407@ni.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 5/14/2015 12:10 PM, Sebastian Andrzej Siewior wrote: > > Do you have any cyclictest numbers how much the latency increases on > heavy iio usage? Traditionally the primary handler should be very quick > / short. > > Sebastian > With no other processes running, I got the following results after a couple of hours on one of our devices: admin at Xander-roboRIO:~# cyclictest -S -m -p 98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 0.01 0.07 0.12 1/176 1473 T: 0 ( 1373) P:98 I:1000 C:6503872 Min: 9 Act: 13 Avg: 13 Max: 51 T: 1 ( 1374) P:98 I:1500 C:4335914 Min: 9 Act: 12 Avg: 13 Max: 49 With a VI reading all default handles (raw, offset, scale, sampling_frequency) in /sys/bus/iio/devices/iio:device0 constantly in a while loop, I got the following results after a couple hours on the same device: admin at Xander-roboRIO:~# cyclictest -S -m -p 98 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 6.93 7.30 7.47 3/182 1530 T: 0 ( 1487) P:98 I:1000 C:4497008 Min: 11 Act: 20 Avg: 21 Max: 69 T: 1 ( 1488) P:98 I:1500 C:2998005 Min: 11 Act: 20 Avg: 22 Max: 59 -- Xander Huff Staff Software Engineer National Instruments