From: Mel Gorman <mgorman@suse.de>
To: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-mm@kvack.org, Michal Nazarewicz <mina86@mina86.com>,
Marek Szyprowski <m.szyprowski@samsung.com>
Subject: Re: [PATCH] cma: cached pageblock type fixup
Date: Tue, 19 Jun 2012 17:26:43 +0100 [thread overview]
Message-ID: <20120619162643.GC8810@suse.de> (raw)
In-Reply-To: <201206191504.59994.b.zolnierkie@samsung.com>
On Tue, Jun 19, 2012 at 03:04:59PM +0200, Bartlomiej Zolnierkiewicz wrote:
> > If the page is on the wrong free list, just isolate it or move it to the
> > MIGRATE_ISOLATE free list at that point. If it has been allocated then
> > migrate it and move the resulting free page to the MIGRATE_ISOLATE list.
>
> Thanks, this makes sense but still leaves us with some page allocation vs
> alloc_contig_range() races (i.e. pages "in-flight" state being added/removed
> to/from pcp lists so not being on the freelists and not being allocated).
>
The races should not be forever or open-ended. Once the pageblock is
marked ISOLATE it should only take one pass to either move it from
MIGRATE_CMA to MIGRATE_ISOLATE free lists or to migrate the page and
free it to the MIGRATE_ISOLATE.
I would be very surprised if this cannot be properly handled in
alloc_contig_range() in a manner that does not wreck the page allocator
fast paths.
--
Mel Gorman
SUSE Labs
--
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:[~2012-06-19 16:26 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-23 7:22 [PATCH] cma: cached pageblock type fixup Bartlomiej Zolnierkiewicz
2012-06-14 13:19 ` Marek Szyprowski
2012-06-19 9:00 ` Mel Gorman
2012-06-19 11:28 ` Bartlomiej Zolnierkiewicz
2012-06-19 12:00 ` Mel Gorman
2012-06-19 13:04 ` Bartlomiej Zolnierkiewicz
2012-06-19 16:26 ` Mel Gorman [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=20120619162643.GC8810@suse.de \
--to=mgorman@suse.de \
--cc=b.zolnierkie@samsung.com \
--cc=linux-mm@kvack.org \
--cc=m.szyprowski@samsung.com \
--cc=mina86@mina86.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;
as well as URLs for NNTP newsgroup(s).