linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Phillip Susi <phill@thesusis.net>
To: Daniel Vetter <daniel@ffwll.ch>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Pavel Machek <pavel@ucw.cz>, Randy Dunlap <rdunlap@infradead.org>,
	LKML <linux-kernel@vger.kernel.org>,
	"linux-doc\@vger.kernel.org" <linux-doc@vger.kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	dri-devel <dri-devel@lists.freedesktop.org>,
	Linux Fbdev development list <linux-fbdev@vger.kernel.org>
Subject: Re: fbcon: remove soft scrollback code (missing Doc. patch)
Date: Tue, 02 Feb 2021 10:13:14 -0500	[thread overview]
Message-ID: <87wnvqts9g.fsf@vps.thesusis.net> (raw)
In-Reply-To: <YBlfKgQ1laQLFqpW@phenom.ffwll.local>


Daniel Vetter writes:

> Just a quick comment on this: Since most framebuffers are write-combining,
> and reads from that tend to be ~3 orders of magnitude slower than writes
> (at least on the pile of machines I looked at here, there's big
> differences, and some special streaming cpu instructions to make the
> reading side not so slow).
>
> So scrolling by copying tends to be significantly slower than just
> redrawing everything.

I know this was the case years ago with AGP as iirc, it doubled ( 4x, 8x
) the PCI clock rate but only for writes wasn't it?  I thought this was
no longer an issue with PCIe, but if it is, then I guess I'll go ahead
with cleaning up the dead code and having it re-render with the larger
text buffer.

  reply	other threads:[~2021-02-02 15:25 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <git-mailbomb-linux-master-50145474f6ef4a9c19205b173da6264a644c7489@kernel.org>
2020-09-15  1:18 ` fbcon: remove soft scrollback code (missing Doc. patch) Randy Dunlap
2020-09-15  1:28   ` Bhaskar Chowdhury
2020-09-15  1:30     ` Linus Torvalds
2020-09-15  1:34     ` Randy Dunlap
2020-09-15  1:28   ` Linus Torvalds
2020-09-16 20:54     ` Pavel Machek
2020-09-18 10:27       ` Adam Borowski
2020-09-30 21:29         ` Maciej W. Rozycki
2021-01-08 19:01       ` Phillip Susi
2021-01-08 23:11         ` Linus Torvalds
2021-01-12 15:00           ` Phillip Susi
2021-01-12 16:11             ` Greg Kroah-Hartman
2021-01-12 15:57           ` Daniel Vetter
2021-01-14 15:56             ` Geert Uytterhoeven
2021-01-14 16:11               ` Daniel Vetter
2021-01-15  8:06                 ` Geert Uytterhoeven
2021-02-03  8:03                   ` Thomas Zimmermann
2021-01-22 18:55               ` Phillip Susi
2021-01-25 15:39                 ` Geert Uytterhoeven
2021-02-02 14:18                 ` Daniel Vetter
2021-02-02 15:13                   ` Phillip Susi [this message]
2021-02-02 15:23                     ` Daniel Vetter
2021-01-14 17:43           ` fbcon: remove soft scrollback code Alan Mackenzie

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87wnvqts9g.fsf@vps.thesusis.net \
    --to=phill@thesusis.net \
    --cc=daniel@ffwll.ch \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=geert@linux-m68k.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-fbdev@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pavel@ucw.cz \
    --cc=rdunlap@infradead.org \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).