Is anyone using ftrace on DaVinci git with success? I'm trying to use the irqsoff tracer to look into an irq latency problem on DM355, but it seems not to be recording small time changes, jumping in units of 10ms.
Example partial trace: ksoftirq-3 0d..1. 0us : finish_task_switch <-trace_hardirqs_on ksoftirq-3 0d..1. 0us : trace_hardirqs_on <-trace_hardirqs_on ksoftirq-3 0d..1. 0us : do_softirq <-trace_hardirqs_off ksoftirq-3 0d.s1. 0us : __do_softirq <-trace_hardirqs_on ksoftirq-3 0d.s1. 0us : trace_hardirqs_on <-trace_hardirqs_on ksoftirq-3 0d.s1. 0us!: hrtimer_peek_ahead_timers <-trace_hardirqs_off ksoftirq-3 0d.s1. 20000us : hrtimer_peek_ahead_timers <-trace_hardirqs_on ksoftirq-3 0d.s1. 20000us : trace_hardirqs_on <-trace_hardirqs_on ksoftirq-3 0d.s1. 20000us : <stack trace> Related, I have an IRQ handler that seems to be getting interrupted for up to 2+ms by something. This surprises me, I thought IRQs should be disabled? I wonder if CONFIG_PREEMPT is related? Any hints welcome. For now I suppose I'll go back to poking around with LED wiggling and logic analyser. -- Jon Povey jon.po...@racelogic.co.uk Racelogic is a limited company registered in England. Registered number 2743719 . Registered Office Unit 10, Swan Business Centre, Osier Way, Buckingham, Bucks, MK18 1TB . The information contained in this electronic mail transmission is intended by Racelogic Ltd for the use of the named individual or entity to which it is directed and may contain information that is confidential or privileged. If you have received this electronic mail transmission in error, please delete it from your system without copying or forwarding it, and notify the sender of the error by reply email so that the sender's address records can be corrected. The views expressed by the sender of this communication do not necessarily represent those of Racelogic Ltd. Please note that Racelogic reserves the right to monitor e-mail communications passing through its network _______________________________________________ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source