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Date: Mon, 08 Apr 2002 15:38:52 -0700
From: Andrew Morton <akpm@zip.com.au>
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To: "Martin J. Bligh" <Martin.Bligh@us.ibm.com>
CC: linux-kernel@vger.kernel.org, Tony.P.Lee@nokia.com, kessler@us.ibm.com,
        alan@lxorguk.ukuu.org.uk, Dave Jones <davej@suse.de>
Subject: Re: Event logging vs enhancing printk
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"Martin J. Bligh" wrote:
> 
>> ...
> 1. There seems to me to be a race within the current SMP code (with or without
> the event logging stuff). It seems that segments of the line could get interspersed
> with segments of another line (or a whole other line) generated by another cpu ...
> is this correct?
> 

I'm not aware of that being the case.  The output string
is formed into a static buffer and then copied into the
printk ring buffer all under spinlock_irqsave(logbuf_lock).

If there is something wrong then it would be occurring
at the other end - where data is taken out of the ring
and is sent to the console device(s).  The locking there
is OK, I think?

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