Re: [PATCH v5 2/2] Output stall data in debugfs

From: Don Zickus
Date: Wed Aug 10 2011 - 09:07:22 EST

On Tue, Aug 09, 2011 at 05:22:43PM -0700, Alex Neronskiy wrote:
> From: Alex Neronskiy <zakmagnus@xxxxxxxxxxxx>
> Instead of using the log, use debugfs for output of both stall
> lengths and stack traces. Printing to the log can result in
> watchdog touches, distorting the very events being measured.
> Additionally, the information will not distract from lockups
> when users view the log.
> A two-buffer system is used to ensure that the trace information
> can always be recorded without contention.

This looks like it can work. I'll try to play with it today. Can I ask
that you add some comments to document the way the buffers work, so others
know what is going on to.

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