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From: xander.huff@ni•com (Xander Huff)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] iio: adc: xilinx-xadc: Convert to raw spinlock
Date: Thu, 14 May 2015 17:45:04 -0500	[thread overview]
Message-ID: <55552570.5050407@ni.com> (raw)
In-Reply-To: <20150514171038.GG13442@linutronix.de>

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

  reply	other threads:[~2015-05-14 22:45 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-07 15:38 [PATCH] iio: adc: xilinx-xadc: Convert to raw spinlock Xander Huff
2015-05-14 17:10 ` Sebastian Andrzej Siewior
2015-05-14 22:45   ` Xander Huff [this message]
2015-05-18 21:17     ` Sebastian Andrzej Siewior
2015-05-23 11:36       ` Jonathan Cameron
2015-06-07 15:29       ` Jonathan Cameron
2015-06-08 14:44         ` Xander Huff
2015-07-08 21:38         ` [PATCH v2] iio: adc: xilinx-xadc: Push interrupts into threaded context Xander Huff
2015-07-14 14:28           ` Sebastian Andrzej Siewior
2015-07-15 15:59             ` Xander Huff
     [not found]           ` <CAKfKVtGTO81wLWk50M303t2WjcBEMEt_LUnsJ3_WmvR_3izUjg@mail.gmail.com>
2015-07-15 15:57             ` Xander Huff
2015-07-20 23:14             ` [PATCH v3] " Xander Huff
2015-07-24 12:38               ` Lars-Peter Clausen
2015-08-03 20:18                 ` Xander Huff
2015-08-04  8:01                   ` Lars-Peter Clausen
2015-08-11 23:00                     ` [PATCH v4] iio: adc: xilinx-xadc: Push interrupts into hardirq context Xander Huff
2015-08-12 15:17                       ` Lars-Peter Clausen
2015-08-12 16:33                         ` Sebastian Andrzej Siewior
2015-08-15 19:55                           ` Jonathan Cameron
2015-08-04  5:34                 ` [PATCH v3] iio: adc: xilinx-xadc: Push interrupts into threaded context Shubhrajyoti Datta
2015-08-04  8:05                   ` Lars-Peter Clausen
2015-08-07  3:55                     ` Shubhrajyoti Datta

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