On Dec 16 2003, at 08:49, Vanitha Ramaswami was caught saying:
> Hi All,
>
> I am running embedded linux on IXP425 Coyote Board.
> I want to measure the time ticks taken to execute a system call.
> I couldnt find timestamp counter processor register for IXP425.
>
> Is there any call equivalent to rdtsc assembly instruction on IXP425 ?
You can use the XScale core's Performance Monitoring Unit (PMU)
to read the number of clock cycles it takes to perform the call.
It's only accessible in svc mode I believe, so you'd have to
place the code in the kernel and log the data in a buffer.
Another option is to read the OSTS register before and after the
system call as this counts timer ticks. DO NOT write to this
register as the kernel uses it. Just mmap() the register into
your process.
Or alternativly, use Linux Trace Toolkit.
~Deepak
--
Deepak Saxena - dsaxena@xxxxxxxxxxx
-------------------------------------------------------------------
Subscription options: http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm
FAQ/Etiquette: http://www.arm.linux.org.uk/armlinux/mailinglists.php
|
