All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: John Hubbard <jhubbard@nvidia.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	linux-mm <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Alexander Gordeev <agordeev@linux.ibm.com>,
	linux-s390@vger.kernel.org, Heiko Carstens <hca@linux.ibm.com>,
	Claudio Imbrenda <imbrenda@linux.ibm.com>
Subject: Re: [RFC PATCH 0/2] mm/gup: fix gup_fast with dynamic page table folding
Date: Wed, 2 Sep 2020 17:13:55 -0300	[thread overview]
Message-ID: <20200902201355.GJ24045@ziepe.ca> (raw)
In-Reply-To: <20200902170958.09be0c3e@thinkpad>

On Wed, Sep 02, 2020 at 05:09:58PM +0200, Gerald Schaefer wrote:
> I guess we *could* assume that all the extra pXd_offset() calls and
> also the de-referencing would be optimized out by the compiler for other
> archs, but it is one example where my gut tells me that this might not
> be so trivial and w/o unwanted effects after all.

Assigning to a variable that is never read should be eliminated.. If
things are very complex then the pXX_offset function might need to be
marked with attribute pure, but I think this should be reliable?

Jason

      reply	other threads:[~2020-09-02 20:13 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-28 14:03 [RFC PATCH 0/2] mm/gup: fix gup_fast with dynamic page table folding Gerald Schaefer
2020-08-28 14:03 ` [RFC PATCH 1/2] " Gerald Schaefer
2020-08-28 14:03 ` [RFC PATCH 2/2] " Gerald Schaefer
2020-08-28 14:21 ` [RFC PATCH 0/2] " Jason Gunthorpe
2020-08-28 15:01   ` Gerald Schaefer
2020-08-28 15:20     ` Jason Gunthorpe
2020-08-31 11:53 ` Christian Borntraeger
2020-08-31 19:15   ` Andrew Morton
2020-09-01 17:40     ` Gerald Schaefer
2020-09-01 18:14       ` Jason Gunthorpe
2020-09-01 23:22       ` John Hubbard
2020-09-01 23:22         ` John Hubbard
2020-09-02 12:24         ` Gerald Schaefer
2020-09-02 12:24           ` Gerald Schaefer
2020-09-02 15:09           ` Gerald Schaefer
2020-09-02 15:09             ` Gerald Schaefer
2020-09-02 20:13             ` Jason Gunthorpe [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=20200902201355.GJ24045@ziepe.ca \
    --to=jgg@ziepe.ca \
    --cc=agordeev@linux.ibm.com \
    --cc=akpm@linux-foundation.org \
    --cc=borntraeger@de.ibm.com \
    --cc=gerald.schaefer@linux.ibm.com \
    --cc=gor@linux.ibm.com \
    --cc=hca@linux.ibm.com \
    --cc=imbrenda@linux.ibm.com \
    --cc=jhubbard@nvidia.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-s390@vger.kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.