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Date: Fri, 18 Nov 2016 18:30:16 +0100
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
To: "Speakup is a screen review system for Linux." <speakup@linux-speakup.org>
Subject: Re: using system serial tty drivers
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David, on Fri 18 Nov 2016 12:02:44 -0500, wrote:
> The purpose of defines is that all drivers will dump the old serial stuff
> eventually.

Yes, but we don't want to do that without testing.

> Just wrappping serial_out to do one character transfers is a
> performance hit big time.

No. We are talking about serial ports, which are very slow anyway.

> that is why I refactored the buffer handlers
> so you can do.

Did you measure any actual performance improvement ?

A function call is at most like a few instructions, i.e. the order of a
nanosecond. On serial ports, at the very very best, characters take an
order of a microsecond to transfer.

Again, complex code is really not what you want in the end if it doesn't
bring much improvement.

Samuel