From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xen.org>
Subject: Re: ns16550.c's poll_port variable
Date: Fri, 04 May 2012 13:03:24 +0100
Message-ID: <CBC9841C.3FAFF%keir@xen.org>
References: <4FA3D4320200007800081987@nat28.tlf.novell.com>
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To: Jan Beulich <JBeulich@suse.com>
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On 04/05/2012 12:05, "Jan Beulich" <JBeulich@suse.com> wrote:

>> I'm unclear on exactly what you want to optimise away? Certainly the 8 bytes
>> per CPU of the poll_port variable isn't worth much optimising effort.
> 
> Certainly not (and as you say they are actually needed, even if
> only rarely). But the pointlessly running timer(s) might be, as might
> the buffer(s) set up via serial_async_transmit().

We could delay {init,setup}_postirq until a corresponding serial handle has
been created via serial_parse_handle()? The logic might be a bit ugly and
spread across both serial.c and ns16550.c but not actually particularly
complicated?

 -- Keir