linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Minchan Kim <minchan@kernel.org>
To: Hillf Danton <dhillf@gmail.com>
Cc: Dave Hansen <dave@sr71.net>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	akpm@linux-foundation.org, mgorman@suse.de,
	tim.c.chen@linux.intel.com
Subject: Re: [v5][PATCH 5/6] mm: vmscan: batch shrink_page_list() locking operations
Date: Wed, 5 Jun 2013 16:57:13 +0900	[thread overview]
Message-ID: <20130605075713.GJ8732@blaptop> (raw)
In-Reply-To: <CAJd=RBAt9eSx3_FB79J93e19bv15sFry-mU6hkUYH80isULszw@mail.gmail.com>

On Wed, Jun 05, 2013 at 03:28:27PM +0800, Hillf Danton wrote:
> On Tue, Jun 4, 2013 at 1:07 PM, Minchan Kim <minchan@kernel.org> wrote:
> > On Tue, Jun 04, 2013 at 09:17:26AM +0800, Hillf Danton wrote:
> >> On Tue, Jun 4, 2013 at 4:02 AM, Dave Hansen <dave@sr71.net> wrote:
> >> > +/*
> >> > + * pages come in here (via remove_list) locked and leave unlocked
> >> > + * (on either ret_pages or free_pages)
> >> > + *
> >> > + * We do this batching so that we free batches of pages with a
> >> > + * single mapping->tree_lock acquisition/release.  This optimization
> >> > + * only makes sense when the pages on remove_list all share a
> >> > + * page_mapping().  If this is violated you will BUG_ON().
> >> > + */
> >> > +static int __remove_mapping_batch(struct list_head *remove_list,
> >> > +                                 struct list_head *ret_pages,
> >> > +                                 struct list_head *free_pages)
> >> > +{
> >> > +       int nr_reclaimed = 0;
> >> > +       struct address_space *mapping;
> >> > +       struct page *page;
> >> > +       LIST_HEAD(need_free_mapping);
> >> > +
> >> > +       if (list_empty(remove_list))
> >> > +               return 0;
> >> > +
> >> > +       mapping = page_mapping(lru_to_page(remove_list));
> >> > +       spin_lock_irq(&mapping->tree_lock);
> >> > +       while (!list_empty(remove_list)) {
> >> > +               page = lru_to_page(remove_list);
> >> > +               BUG_ON(!PageLocked(page));
> >> > +               BUG_ON(page_mapping(page) != mapping);
> >> > +               list_del(&page->lru);
> >> > +
> >> > +               if (!__remove_mapping(mapping, page)) {
> >> > +                       unlock_page(page);
> >> > +                       list_add(&page->lru, ret_pages);
> >> > +                       continue;
> >> > +               }
> >> > +               list_add(&page->lru, &need_free_mapping);
> >> > +       }
> >> > +       spin_unlock_irq(&mapping->tree_lock);
> >> > +
> >> While reclaiming pages, can we open ears upon IRQ controller,
> >> if the page list length is over 10, or even 20?
> >
> > At the moment, it implicitly could be bounded by SWAP_CLUSTER_MAX and
> 
> Could we reclaim a THP currently?

You mean that we could have (512 * SWAP_CLUSTER_MAX) pages in
page_list as worst case?
Yes but in that case, we drain batch_for_mapping_rm by [6/6] so
THP page couldn't be a problem, IMO.

-- 
Kind regards,
Minchan Kim

--
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>

  reply	other threads:[~2013-06-05  7:57 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-03 20:02 [v5][PATCH 0/6] mm: vmscan: Batch page reclamation under shink_page_list Dave Hansen
2013-06-03 20:02 ` [v5][PATCH 1/6] mm: swap: defer clearing of page_private() for swap cache pages Dave Hansen
2013-07-14 23:47   ` Wanpeng Li
2013-07-14 23:47   ` Wanpeng Li
2013-06-03 20:02 ` [v5][PATCH 2/6] mm: swap: make 'struct page' and swp_entry_t variants of swapcache_free() Dave Hansen
2013-07-14 23:48   ` Wanpeng Li
2013-07-14 23:48   ` Wanpeng Li
2013-06-03 20:02 ` [v5][PATCH 3/6] mm: vmscan: break up __remove_mapping() Dave Hansen
2013-07-14 23:49   ` Wanpeng Li
2013-07-14 23:49   ` Wanpeng Li
2013-06-03 20:02 ` [v5][PATCH 4/6] mm: vmscan: break out mapping "freepage" code Dave Hansen
2013-07-14 23:49   ` Wanpeng Li
2013-07-14 23:49   ` Wanpeng Li
2013-06-03 20:02 ` [v5][PATCH 5/6] mm: vmscan: batch shrink_page_list() locking operations Dave Hansen
2013-06-04  1:17   ` Hillf Danton
2013-06-04  5:07     ` Minchan Kim
2013-06-04 15:22       ` Dave Hansen
2013-06-05  7:28       ` Hillf Danton
2013-06-05  7:57         ` Minchan Kim [this message]
2013-06-05 14:24         ` Dave Hansen
2013-06-04  5:01   ` Minchan Kim
2013-06-04  6:02     ` Minchan Kim
2013-06-04 15:29       ` Dave Hansen
2013-06-04 23:32         ` Minchan Kim
2013-06-04  6:10     ` Dave Hansen
2013-06-04  6:59       ` Minchan Kim
2013-07-14 23:50       ` Wanpeng Li
2013-07-14 23:50       ` Wanpeng Li
2013-06-03 20:02 ` [v5][PATCH 6/6] mm: vmscan: drain batch list during long operations Dave Hansen
2013-06-04  6:05   ` Minchan Kim
2013-06-04 15:24     ` Dave Hansen
2013-06-04 23:23       ` Minchan Kim
2013-06-04 23:31         ` Dave Hansen
2013-06-04 23:36           ` Minchan Kim
2013-06-04 23:37   ` Minchan Kim
2013-07-14 23:51   ` Wanpeng Li
2013-07-14 23:51   ` Wanpeng Li

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=20130605075713.GJ8732@blaptop \
    --to=minchan@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=dave@sr71.net \
    --cc=dhillf@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=tim.c.chen@linux.intel.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).