From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg KH <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 2/3] RFC: Solved unnecessary schedule latency in the TTY
 layer (2/3)
Date: Thu, 3 May 2012 09:25:29 -0700
Message-ID: <20120503162529.GB3063@kroah.com>
References: <1336048663-21882-1-git-send-email-meltedpianoman@gmail.com>
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To: Ivo Sieben <meltedpianoman@gmail.com>
Cc: linux-serial@vger.kernel.org, Alan Cox <alan@linux.intel.com>, RT <linux-rt-users@vger.kernel.org>

On Thu, May 03, 2012 at 02:37:42PM +0200, Ivo Sieben wrote:
> Solved unnecessary schedule latency in the TTY layer when used in
> realtime context:
> The global "normal" spin lock that guards the line discipline
> administration is replaced by a raw spin lock.

Why, what does this cause to have happen?  What's the difference here
that causes any speedups or latency fixes?

thanks,

greg k-h