Linux-HyperV Archive on lore.kernel.org
 help / color / Atom feed
From: Wei Yang <richard.weiyang@linux.alibaba.com>
To: David Hildenbrand <david@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	linux-hyperv@vger.kernel.org, xen-devel@lists.xenproject.org,
	linux-acpi@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Alexander Duyck <alexander.h.duyck@linux.intel.com>,
	Mel Gorman <mgorman@techsingularity.net>,
	Michal Hocko <mhocko@kernel.org>,
	Dave Hansen <dave.hansen@intel.com>,
	Vlastimil Babka <vbabka@suse.cz>,
	Wei Yang <richard.weiyang@linux.alibaba.com>,
	Oscar Salvador <osalvador@suse.de>,
	Mike Rapoport <rppt@kernel.org>
Subject: Re: [PATCH v1 5/5] mm/memory_hotplug: update comment regarding zone shuffling
Date: Tue, 29 Sep 2020 17:40:21 +0800
Message-ID: <20200929094021.GD36904@L-31X9LVDL-1304.local> (raw)
In-Reply-To: <20200928182110.7050-6-david@redhat.com>

On Mon, Sep 28, 2020 at 08:21:10PM +0200, David Hildenbrand wrote:
>As we no longer shuffle via generic_online_page() and when undoing
>isolation, we can simplify the comment.
>
>We now effectively shuffle only once (properly) when onlining new
>memory.
>
>Cc: Andrew Morton <akpm@linux-foundation.org>
>Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
>Cc: Mel Gorman <mgorman@techsingularity.net>
>Cc: Michal Hocko <mhocko@kernel.org>
>Cc: Dave Hansen <dave.hansen@intel.com>
>Cc: Vlastimil Babka <vbabka@suse.cz>
>Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
>Cc: Oscar Salvador <osalvador@suse.de>
>Cc: Mike Rapoport <rppt@kernel.org>
>Signed-off-by: David Hildenbrand <david@redhat.com>

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>

>---
> mm/memory_hotplug.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
>diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
>index 9db80ee29caa..c589bd8801bb 100644
>--- a/mm/memory_hotplug.c
>+++ b/mm/memory_hotplug.c
>@@ -859,13 +859,10 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
> 	undo_isolate_page_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE);
> 
> 	/*
>-	 * When exposing larger, physically contiguous memory areas to the
>-	 * buddy, shuffling in the buddy (when freeing onlined pages, putting
>-	 * them either to the head or the tail of the freelist) is only helpful
>-	 * for maintaining the shuffle, but not for creating the initial
>-	 * shuffle. Shuffle the whole zone to make sure the just onlined pages
>-	 * are properly distributed across the whole freelist. Make sure to
>-	 * shuffle once pageblocks are no longer isolated.
>+	 * Freshly onlined pages aren't shuffled (e.g., all pages are placed to
>+	 * the tail of the freelist when undoing isolation). Shuffle the whole
>+	 * zone to make sure the just onlined pages are properly distributed
>+	 * across the whole freelist - to create an initial shuffle.
> 	 */
> 	shuffle_zone(zone);
> 
>-- 
>2.26.2

-- 
Wei Yang
Help you, Help me

  reply index

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-28 18:21 [PATCH v1 0/5] mm: place pages to the freelist tail when onling and undoing isolation David Hildenbrand
2020-09-28 18:21 ` [PATCH v1 1/5] mm/page_alloc: convert "report" flag of __free_one_page() to a proper flag David Hildenbrand
2020-09-28 20:11   ` Pankaj Gupta
2020-09-29  8:58   ` Wei Yang
2020-10-02 13:17   ` Michal Hocko
2020-10-02 13:41   ` Matthew Wilcox
2020-10-02 14:48     ` David Hildenbrand
2020-10-02 14:57       ` David Hildenbrand
2020-09-28 18:21 ` [PATCH v1 2/5] mm/page_alloc: place pages to tail in __putback_isolated_page() David Hildenbrand
2020-09-28 20:38   ` Pankaj Gupta
2020-09-29  9:10   ` Wei Yang
2020-10-02 13:19   ` Michal Hocko
2020-09-28 18:21 ` [PATCH v1 3/5] mm/page_alloc: always move pages to the tail of the freelist in unset_migratetype_isolate() David Hildenbrand
2020-09-28 20:55   ` Pankaj Gupta
2020-09-29  9:18   ` Wei Yang
2020-09-29 10:12     ` David Hildenbrand
2020-09-30  7:48       ` Wei Yang
2020-10-02 13:24   ` Michal Hocko
2020-10-02 15:20     ` David Hildenbrand
2020-10-05  6:56       ` Michal Hocko
2020-10-05  8:20         ` Mel Gorman
2020-10-05  9:11           ` David Hildenbrand
2020-09-28 18:21 ` [PATCH v1 4/5] mm/page_alloc: place pages to tail in __free_pages_core() David Hildenbrand
2020-09-28 20:33   ` Pankaj Gupta
2020-09-29  9:36   ` Wei Yang
2020-09-29 10:14     ` David Hildenbrand
2020-10-02 13:41   ` Michal Hocko
2020-10-02 15:10     ` David Hildenbrand
2020-09-28 18:21 ` [PATCH v1 5/5] mm/memory_hotplug: update comment regarding zone shuffling David Hildenbrand
2020-09-29  9:40   ` Wei Yang [this message]
2020-10-02 13:41   ` 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=20200929094021.GD36904@L-31X9LVDL-1304.local \
    --to=richard.weiyang@linux.alibaba.com \
    --cc=akpm@linux-foundation.org \
    --cc=alexander.h.duyck@linux.intel.com \
    --cc=dave.hansen@intel.com \
    --cc=david@redhat.com \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-hyperv@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@techsingularity.net \
    --cc=mhocko@kernel.org \
    --cc=osalvador@suse.de \
    --cc=rppt@kernel.org \
    --cc=vbabka@suse.cz \
    --cc=xen-devel@lists.xenproject.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

Linux-HyperV Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-hyperv/0 linux-hyperv/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-hyperv linux-hyperv/ https://lore.kernel.org/linux-hyperv \
		linux-hyperv@vger.kernel.org
	public-inbox-index linux-hyperv

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-hyperv


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git