From: Christoph Lameter <cl@linux.com>
To: Matthew Wilcox <willy@infradead.org>
Cc: linux-mm@kvack.org, Jesper Dangaard Brouer <brouer@redhat.com>,
riel@redhat.com, Mel Gorman <mel@csn.ul.ie>
Subject: Re: [LSF/MM TOPIC] Movable memory and reliable higher order allocations
Date: Thu, 2 Mar 2017 11:00:52 -0600 (CST) [thread overview]
Message-ID: <alpine.DEB.2.20.1703021100320.31249@east.gentwo.org> (raw)
In-Reply-To: <20170228231733.GI16328@bombadil.infradead.org>
On Tue, 28 Feb 2017, Matthew Wilcox wrote:
> The radix tree is not movable given its current API. In order to move
> a node, we need to be able to lock the tree to prevent simultaneous
> modification by another CPU. But the radix tree API makes callers
> responsible for their own locking -- we don't even know if it's locked
> by a mutex or a spinlock, much less which lock protects this tree.
>
> This was one of my motivations for the xarray. The xarray handles its own
> locking, so we can always lock out other CPUs from modifying the array.
> We still have to take care of RCU walkers, but that's straightforward
> to handle. I have a prototype patch for the radix tree (ignoring the
> locking problem), so I can port that over to the xarray and post that
> for comment tomorrow.
Great. Thanks.
--
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>
prev parent reply other threads:[~2017-03-02 17:00 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-28 21:32 Christoph Lameter
2017-02-28 23:17 ` Matthew Wilcox
2017-03-02 4:12 ` Matthew Wilcox
2017-03-02 17:26 ` Christoph Lameter
2017-03-02 20:55 ` Matthew Wilcox
2017-03-03 15:24 ` Christoph Lameter
2017-03-03 20:39 ` Matthew Wilcox
2017-03-06 14:53 ` Christoph Lameter
2017-03-02 17:00 ` Christoph Lameter [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=alpine.DEB.2.20.1703021100320.31249@east.gentwo.org \
--to=cl@linux.com \
--cc=brouer@redhat.com \
--cc=linux-mm@kvack.org \
--cc=mel@csn.ul.ie \
--cc=riel@redhat.com \
--cc=willy@infradead.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