Re: Using sched_clock for mmio-trace

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Jeff Muizelaar <[email protected]> writes:

> I've built a tool with the goal of logging mmio writes and reads by
> device drivers. See http://nouveau.freedesktop.org/wiki/MmioTrace.

FWIW, this is exactly a type of add-on trace patch that could be
mooted by adoption of the ltt/systemtap "marker" facility.  With it,
you would not need so much code (e.g. no new user-space tools at all,
reuse of common tracing buffer logic, permanently placed hooks) and
would probably get more utility.

> [...]  The question is, what [timer] api should I be using? I need
> something that can be called from inside interrupt handlers, and
> obviously the more accurate and the lower the overhead the better.

We in systemtap land have the same problem, and so far made do with
slightly postprocessed per-cpu TSC values.


- FChE
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux