All of lore.kernel.org
 help / color / mirror / Atom feed
From: Michal Hocko <mhocko@kernel.org>
To: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Zi Yan <ziy@nvidia.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	mike.kravetz@oracle.com, osalvador@suse.de,
	akpm@linux-foundation.org
Subject: Re: [PATCH] mm/isolation: Remove redundant pfn_valid_within() in __first_valid_page()
Date: Thu, 21 Mar 2019 09:07:02 +0100	[thread overview]
Message-ID: <20190321080702.GG8696@dhcp22.suse.cz> (raw)
In-Reply-To: <cda4f247-4eea-decf-3f4a-3dc09364de27@arm.com>

On Thu 21-03-19 11:03:18, Anshuman Khandual wrote:
> 
> 
> On 03/21/2019 10:31 AM, Zi Yan wrote:
> > On 20 Mar 2019, at 21:13, Anshuman Khandual wrote:
> > 
> >> pfn_valid_within() calls pfn_valid() when CONFIG_HOLES_IN_ZONE making it
> >> redundant for both definitions (w/wo CONFIG_MEMORY_HOTPLUG) of the helper
> >> pfn_to_online_page() which either calls pfn_valid() or pfn_valid_within().
> >> pfn_valid_within() being 1 when !CONFIG_HOLES_IN_ZONE is irrelevant either
> >> way. This does not change functionality.
> >>
> >> Fixes: 2ce13640b3f4 ("mm: __first_valid_page skip over offline pages")
> > 
> > I would not say this patch fixes the commit 2ce13640b3f4 from 2017,
> > because the pfn_valid_within() in pfn_to_online_page() was introduced by
> > a recent commit b13bc35193d9e last month. :)
> 
> Right, will update the tag with this commit.

The patch is correct but I wouldn't bother to add Fixes tag at all. The
current code is obviously not incorrect. Do you see any actual
performance issue?
-- 
Michal Hocko
SUSE Labs

  reply	other threads:[~2019-03-21  8:07 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-21  4:13 [PATCH] mm/isolation: Remove redundant pfn_valid_within() in __first_valid_page() Anshuman Khandual
2019-03-21  5:01 ` Zi Yan
2019-03-21  5:33   ` Anshuman Khandual
2019-03-21  8:07     ` Michal Hocko [this message]
2019-03-21  8:13       ` Anshuman Khandual
2019-03-21  9:42 ` Oscar Salvador
2019-03-21 10:03   ` Michal Hocko
2019-03-22  9:23 ` Michal Hocko

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=20190321080702.GG8696@dhcp22.suse.cz \
    --to=mhocko@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=anshuman.khandual@arm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mike.kravetz@oracle.com \
    --cc=osalvador@suse.de \
    --cc=ziy@nvidia.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 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.