From: Jean Delvare <jdelvare@suse.de>
To: Takashi Iwai <tiwai@suse.de>
Cc: David Airlie <airlied@redhat.com>,
christian.koenig@amd.com,
dri-devel <dri-devel@lists.freedesktop.org>,
linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: Performance regression in ast drm driver
Date: Mon, 12 Nov 2018 17:41:44 +0100 [thread overview]
Message-ID: <1542040904.2661.35.camel@suse.de> (raw)
In-Reply-To: <s5hh8gmfj7a.wl-tiwai@suse.de>
On Mon, 2018-11-12 at 15:45 +0100, Takashi Iwai wrote:
> On Mon, 12 Nov 2018 15:36:07 +0100,
> Jean Delvare wrote:
> > Takashi asked me to compare the contents of
> > /sys/kernel/debug/x86/pat_memtype_list before and after the commit
> > above. Before the commit, we have:
> >
> > uncached-minus @ 0xfafe0000-0xfb000000
> > uncached-minus @ 0xfb000000-0xfb005000
> > write-combining @ 0xfb005000-0xfb584000
> >
> > After the commit, we have:
> >
> > uncached-minus @ 0xfafe0000-0xfb000000
> > uncached-minus @ 0xfb000000-0xfb005000
> > uncached-minus @ 0xfb000000-0xfb800000
> > uncached-minus @ 0xfb005000-0xfb584000
>
> Just to be sure:
> could you double-check whether you're checking the right order
> (i.e. not checking against the revert)? The change above looks
> illogical from what I can see from the commit...
Yes, I double checked and can only confirm what I wrote above. However
while checking I noticed another strange thing: the contents of
pat_memtype_list depend on whether I'm reading the file from an xterm
or from the text console (Ctrl+Alt+F2). So I summarize again:
Commit "drm/drivers: add support for using the arch wc mapping API"
APPLIED, reading pat_memtype_list from the text console:
uncached-minus @ 0xfafe0000-0xfb000000
uncached-minus @ 0xfb000000-0xfb005000
uncached-minus @ 0xfb000000-0xfb800000
uncached-minus @ 0xfb005000-0xfb584000
Commit "drm/drivers: add support for using the arch wc mapping API"
APPLIED, reading pat_memtype_list from an xterm:
uncached-minus @ 0xfafe0000-0xfb000000
uncached-minus @ 0xfb000000-0xfb005000
uncached-minus @ 0xfb000000-0xfb800000
Commit "drm/drivers: add support for using the arch wc mapping API"
REVERTED, reading pat_memtype_list from the text console:
uncached-minus @ 0xfafe0000-0xfb000000
uncached-minus @ 0xfb000000-0xfb005000
write-combining @ 0xfb005000-0xfb584000
Commit "drm/drivers: add support for using the arch wc mapping API"
REVERTED, reading pat_memtype_list from an xterm:
uncached-minus @ 0xfafe0000-0xfb000000
uncached-minus @ 0xfb000000-0xfb005000
If you don't find it logical, remember that if things were the way they
are supposed to be, customers and myself would not be reporting this
bug ;-)
--
Jean Delvare
SUSE L3 Support
next prev parent reply other threads:[~2018-11-12 16:41 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-01 15:27 Performance regression in ast drm driver Jean Delvare
2018-11-08 12:05 ` Jean Delvare
2018-11-09 0:04 ` David Airlie
2018-11-10 8:39 ` Jean Delvare
2018-11-12 14:36 ` Jean Delvare
2018-11-12 14:45 ` Takashi Iwai
2018-11-12 16:41 ` Jean Delvare [this message]
2018-11-13 9:23 ` Thomas Zimmermann
2018-11-13 12:08 ` Jean Delvare
2018-11-13 12:16 ` Thomas Zimmermann
2018-11-12 19:36 ` Thomas Zimmermann
2018-11-13 8:19 ` YC Chen
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=1542040904.2661.35.camel@suse.de \
--to=jdelvare@suse.de \
--cc=airlied@redhat.com \
--cc=christian.koenig@amd.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tiwai@suse.de \
/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).