From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samo Pogacnik <samo_pogacnik@t-2.net>
Subject: Re: [PATCH] detour TTY driver - now ttyprintk
Date: Sat, 26 Jun 2010 03:48:31 +0200
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-embedded <linux-embedded@vger.kernel.org>, linux kernel <linux-kernel@vger.kernel.org>

> > +static int tpk_write_room(struct tty_struct *tty)
> > +{
> > +	int ret = tpk_space;
> > +
> > +	/* allow char by char under max pressure */
> > +	if (tpk_space == 0)
> > +		tpk_space = 1;
> 
> That won't do what you think, the ldisc will keep seeing progress and
> generate millions of 1 byte I/Os in a loop !

I thought that this would automatically reduce processor load, which is
obviously not the case. Sorry for the delay, but i am trying to figure
out how to slow down write method when under pressure.

And that setting tpk_space to 1 would then be just in case we reach 0 to
enable further processing.

Samo