Messages in this thread | | | Date | Sat, 4 Mar 2017 12:19:45 +0300 | From | Alexander Gerasiov <> | Subject | Re: [PATCH 8/8] LinuxPPS: pps_gen_parport: Add check for bad clocksource. |
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Hello Rodolfo,
I should say, that I found this solution is not the best. For example on high speed PCs (I think over 3GHz) 5 iteration is not enough and module stops working after several hours. That makes it not user-friendly, cause user had to calibrate and set failure_iterations manually.
It would be better to use pre-measured loops_per_jiffy (from delay.h) some way.
On Sat, 4 Mar 2017 08:44:03 +0100 Rodolfo Giometti <giometti@enneenne.com> wrote:
> On 02/15/17 15:31, Andrey Drobyshev wrote: > > From: Nikita Edward Baruzdin <nebaruzdin@gmail.com> > > > > This commit is supposed to resolve the issue with hard lockups on > > systems using jiffies as their clock source. Namely, it sets limits > > on number of iterations clock source may remain unchanged (i. e. > > not being updated for one reason or another, as it is with jiffies > > clock source), and on unsuccessful getnstimeofday() polls as well. > > In case limit is reached, we consider clock source incompatible > > with this driver or unstable. > > > > Considering this issue to be fixed, un-BROKEN pps_gen_parport. > > > > For explanation of the problem see this thread on lkml: > > https://lkml.org/lkml/2011/2/18/310 > > > > Signed-off-by: Nikita Edward Baruzdin <nebaruzdin@lvk.cs.msu.su> > > Signed-off-by: Alexander GQ Gerasiov <gq@cs.msu.su> > > Acked-by: Rodolfo Giometti <giometti@enneenne.com>
-- Best regards, Alexander Gerasiov
Contacts: e-mail: gq@cs.msu.su Homepage: http://gerasiov.net Skype: gerasiov PGP fingerprint: 04B5 9D90 DF7C C2AB CD49 BAEA CA87 E9E8 2AAC 33F1
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