From: Christoph Lameter <cl@linux.com>
To: Jan Kara <jack@suse.cz>
Cc: Roland Dreier <roland@kernel.org>,
linux-rdma@vger.kernel.org, linux-mm@kvack.org
Subject: Re: Infiniband use of get_user_pages()
Date: Wed, 24 Apr 2013 15:43:58 +0000 [thread overview]
Message-ID: <0000013e3cb72e66-58330751-246a-4ac4-94d7-897754e59b3d-000000@email.amazonses.com> (raw)
In-Reply-To: <20130424153810.GA25958@quack.suse.cz>
On Wed, 24 Apr 2013, Jan Kara wrote:
> Hello,
>
> when checking users of get_user_pages() (I'm doing some cleanups in that
> area to fix filesystem's issues with mmap_sem locking) I've noticed that
> infiniband drivers add number of pages obtained from get_user_pages() to
> mm->pinned_vm counter. Although this makes some sence, it doesn't match
> with any other user of get_user_pages() (e.g. direct IO) so has infiniband
> some special reason why it does so?
get_user_pages typically is used to temporarily increase the refcount. The
Infiniband layer needs to permanently pin the pages for memory
registration.
--
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>
next prev parent reply other threads:[~2013-04-24 15:44 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-24 15:38 Jan Kara
2013-04-24 15:43 ` Christoph Lameter [this message]
2013-04-24 22:25 ` Roland Dreier
2013-04-25 13:21 ` Jan Kara
2013-04-29 18:44 ` Roland Dreier
2013-04-26 17:19 ` KOSAKI Motohiro
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=0000013e3cb72e66-58330751-246a-4ac4-94d7-897754e59b3d-000000@email.amazonses.com \
--to=cl@linux.com \
--cc=jack@suse.cz \
--cc=linux-mm@kvack.org \
--cc=linux-rdma@vger.kernel.org \
--cc=roland@kernel.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