linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
To: Ralf Baechle <ralf@linux-mips.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>,
	"linux-xtensa@linux-xtensa.org" <linux-xtensa@linux-xtensa.org>,
	Chris Zankel <chris@zankel.net>, Marc Gauthier <marc@cadence.com>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
	"linux-mips@linux-mips.org" <linux-mips@linux-mips.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	David Rientjes <rientjes@google.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Steven J. Hill" <Steven.Hill@imgtec.com>
Subject: Re: [PATCH v4 0/2] mm/highmem: make kmap cache coloring aware
Date: Tue, 26 Aug 2014 18:37:52 +0000	[thread overview]
Message-ID: <nlshxsgfkahrb2t7cl2hk6q5.1409078269675@email.android.com> (raw)
In-Reply-To: <20140825171600.GH25892@linux-mips.org>

16KB page size solution may sometime be a solution:

1) in microcontroller environment then small pages have advantage
in small applications world.

2) some kernel drivers may not fit well a different page size, especially if HW
has an embedded memory translation: GPU, video/audio decoders,
supplement accelerators.

3) finally, somebody can increase cache size faster than page size,
this race never finishes.



Ralf Baechle <ralf@linux-mips.org> wrote:


On Sat, Aug 02, 2014 at 05:11:37AM +0400, Max Filippov wrote:

> this series adds mapping color control to the generic kmap code, allowing
> architectures with aliasing VIPT cache to use high memory. There's also
> use example of this new interface by xtensa.

I haven't actually ported this to MIPS but it certainly appears to be
the right framework to get highmem aliases handled on MIPS, too.

Though I still consider increasing PAGE_SIZE to 16k the preferable
solution because it will entirly do away with cache aliases.

Thanks,

  Ralf

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

      parent reply	other threads:[~2014-08-26 18:38 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-02  1:11 Max Filippov
2014-08-02  1:11 ` [PATCH v4 1/2] " Max Filippov
2014-08-02  1:11 ` [PATCH v4 2/2] xtensa: support aliasing cache in kmap Max Filippov
2014-08-25 17:16 ` [PATCH v4 0/2] mm/highmem: make kmap cache coloring aware Ralf Baechle
2014-08-25 23:55   ` Joshua Kinard
2014-08-26  0:36     ` David Daney
2014-08-26  2:41       ` Joshua Kinard
2014-08-26 17:45         ` David Daney
2014-08-27  1:04           ` Joshua Kinard
2014-08-26 18:37   ` Leonid Yegoshin [this message]

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=nlshxsgfkahrb2t7cl2hk6q5.1409078269675@email.android.com \
    --to=leonid.yegoshin@imgtec.com \
    --cc=Steven.Hill@imgtec.com \
    --cc=akpm@linux-foundation.org \
    --cc=chris@zankel.net \
    --cc=jcmvbkbc@gmail.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@linux-mips.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-xtensa@linux-xtensa.org \
    --cc=marc@cadence.com \
    --cc=ralf@linux-mips.org \
    --cc=rientjes@google.com \
    /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