From: Mike Kravetz <mike.kravetz@oracle.com>
To: Matthew Wilcox <willy@infradead.org>
Cc: Cheng Li <lic121@chinatelecom.cn>,
akpm@linux-foundation.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: use mem_map_offset instead of mem_map_next
Date: Tue, 6 Sep 2022 10:04:52 -0700 [thread overview]
Message-ID: <Yxd9tA8ThZtB77dq@monkey> (raw)
In-Reply-To: <YxUVZpsmukNW5NyK@casper.infradead.org>
On 09/04/22 22:15, Matthew Wilcox wrote:
> On Sun, Sep 04, 2022 at 02:02:41PM +0000, Cheng Li wrote:
> > To handle discontiguity case, mem_map_next() has a parameter named
> > `offset`. As a function caller, one would be confused why "get
> > next entry" needs a parameter named "offset". The other drawback of
> > mem_map_next() is that the callers must take care of the map between
> > parameter "iter" and "offset", otherwise we may get an hole or
> > duplication during iteration. So we use mem_map_offset instead of
> > mem_map_next.
>
> I think we should go further and get rid of mem_map_offset().
> nth_page() is now more efficient than mem_map_offset().
Agree.
However, IIUC nth_page() will 'almost' always be more efficient. The
only exception is unlikely configuration where CONFIG_SPARSEMEM &&
!CONFIG_SPARSEMEM_VMEMMAP. Correct?
Not arguing against replacement. Just wanting to refresh my memory.
--
Mike Kravetz
prev parent reply other threads:[~2022-09-06 17:05 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-04 14:02 [PATCH] mm: use mem_map_offset instead of mem_map_next Cheng Li
2022-09-04 16:38 ` kernel test robot
2022-09-04 17:00 ` kernel test robot
2022-09-04 21:15 ` Matthew Wilcox
2022-09-06 17:04 ` Mike Kravetz [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=Yxd9tA8ThZtB77dq@monkey \
--to=mike.kravetz@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=lic121@chinatelecom.cn \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.