From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Matthew Wilcox <willy@infradead.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>,
Johannes Weiner <hannes@cmpxchg.org>,
Linux-MM <linux-mm@kvack.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Hugh Dickins <hughd@google.com>
Subject: Re: a question of split_huge_page
Date: Thu, 9 Jul 2020 19:07:50 +0300 [thread overview]
Message-ID: <20200709160750.utl46xvavceuvnom@box> (raw)
In-Reply-To: <20200709155002.GF12769@casper.infradead.org>
On Thu, Jul 09, 2020 at 04:50:02PM +0100, Matthew Wilcox wrote:
> On Thu, Jul 09, 2020 at 11:11:11PM +0800, Alex Shi wrote:
> > Hi Kirill & Matthew,
> >
> > In the func call chain, from split_huge_page() to lru_add_page_tail(),
> > Seems tail pages are added to lru list at line 963, but in this scenario
> > the head page has no lru bit and isn't set the bit later. Why we do this?
> > or do I miss sth?
>
> I don't understand how we get to split_huge_page() with a page that's
> not on an LRU list. Both anonymous and page cache pages should be on
> an LRU list. What am I missing?
Right, and it's never got removed from LRU during the split. The tail
pages have to be added to LRU because they now separate from the tail
page.
--
Kirill A. Shutemov
next prev parent reply other threads:[~2020-07-09 16:07 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-09 15:11 Alex Shi
2020-07-09 15:50 ` Matthew Wilcox
2020-07-09 16:07 ` Kirill A. Shutemov [this message]
2020-07-10 4:51 ` Alex Shi
2020-07-10 5:28 ` Mika Penttilä
2020-07-10 7:00 ` Alex Shi
2020-07-10 7:22 ` Mika Penttilä
2020-07-10 9:34 ` Alex Shi
2020-07-10 12:56 ` Joerg Roedel
2020-07-10 17:29 ` Yang Shi
2020-07-10 10:33 ` Kirill A. Shutemov
2020-07-10 14:23 ` Alex Shi
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=20200709160750.utl46xvavceuvnom@box \
--to=kirill@shutemov.name \
--cc=alex.shi@linux.alibaba.com \
--cc=hannes@cmpxchg.org \
--cc=hughd@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--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