From: Andi Kleen <andi@firstfloor.org>
To: Alex Neronskiy <zakmagnus@chromium.org>
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org,
Ingo Molnar <mingo@elte.hu>, Don Zickus <dzickus@redhat.com>,
Mandeep Singh Baines <msb@chromium.org>,
Alex Neronskiy <zakmagnus@chromium.com>
Subject: Re: [PATCH v6 2/2] Output stall data in debugfs
Date: Thu, 11 Aug 2011 11:48:26 -0700 [thread overview]
Message-ID: <m2bovvn5s5.fsf@firstfloor.org> (raw)
In-Reply-To: <1312999364-21104-2-git-send-email-zakmagnus@chromium.org> (Alex Neronskiy's message of "Wed, 10 Aug 2011 11:02:44 -0700")
Alex Neronskiy <zakmagnus@chromium.org> writes:
> From: Alex Neronskiy <zakmagnus@chromium.com>
>
> 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,
Why? Because of printk being slow or something else?
The first could be probably workarounded, especially if you
already have "two buffers"
> 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 implies that kernel bug reports will often not contain the
back trace, right? Seems like a bad thing to me because it will
make bug reports worse.
-Andi
--
ak@linux.intel.com -- Speaking for myself only
next prev parent reply other threads:[~2011-08-11 18:48 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-08-10 18:02 [PATCH v6 1/2] Track hard and soft "short lockups" or "stalls." Alex Neronskiy
2011-08-10 18:02 ` [PATCH v6 2/2] Output stall data in debugfs Alex Neronskiy
2011-08-11 18:48 ` Andi Kleen [this message]
2011-08-11 19:04 ` Don Zickus
2011-08-11 21:05 ` Andi Kleen
2011-08-11 19:13 ` Peter Zijlstra
2011-08-11 19:35 ` Peter Zijlstra
2011-08-11 20:10 ` Alex Neronskiy
2011-08-11 20:23 ` Peter Zijlstra
2011-08-11 20:31 ` Alex Neronskiy
2011-08-11 21:17 ` Peter Zijlstra
2011-08-11 22:02 ` Alex Neronskiy
2011-08-11 23:00 ` Mandeep Singh Baines
2011-08-12 12:14 ` Peter Zijlstra
2011-08-16 19:32 ` Mandeep Singh Baines
2011-08-12 9:06 ` Ingo Molnar
2011-08-12 19:46 ` Alex Neronskiy
2011-08-11 19:43 ` Peter Zijlstra
2011-08-11 19:51 ` Alex Neronskiy
2011-08-11 19:57 ` Peter Zijlstra
2011-08-11 19:09 ` [PATCH v6 1/2] Track hard and soft "short lockups" or "stalls." Peter Zijlstra
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