linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Anshuman Khandual <anshuman.khandual@arm.com>
To: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Michal Hocko <mhocko@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	"xishi.qiuxishi@alibaba-inc.com" <xishi.qiuxishi@alibaba-inc.com>,
	Laurent Dufour <ldufour@linux.vnet.ibm.com>
Subject: Re: [RFC][PATCH v1 11/11] mm: hwpoison: introduce clear_hwpoison_free_buddy_page()
Date: Wed, 14 Nov 2018 13:53:04 +0530	[thread overview]
Message-ID: <b5fb36d0-487c-cf6d-3aa0-a5b43c51b2d6@arm.com> (raw)
In-Reply-To: <20181113001907.GD5945@hori1.linux.bs1.fc.nec.co.jp>



On 11/13/2018 05:49 AM, Naoya Horiguchi wrote:
> On Fri, Nov 09, 2018 at 05:03:06PM +0530, Anshuman Khandual wrote:
>>
>>
>> On 11/09/2018 12:17 PM, Naoya Horiguchi wrote:
>>> The new function is a reverse operation of set_hwpoison_free_buddy_page()
>>> to adjust unpoison_memory() to the new semantics.
>>>
>>> Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
>>
>> snip
>>
>>> +
>>> +/*
>>> + * Reverse operation of set_hwpoison_free_buddy_page(), which is expected
>>> + * to work only on error pages isolated from buddy allocator.
>>> + */
>>> +bool clear_hwpoison_free_buddy_page(struct page *page)
>>> +{
>>> +	struct zone *zone = page_zone(page);
>>> +	bool unpoisoned = false;
>>> +
>>> +	spin_lock(&zone->lock);
>>> +	if (TestClearPageHWPoison(page)) {
>>> +		unsigned long pfn = page_to_pfn(page);
>>> +		int migratetype = get_pfnblock_migratetype(page, pfn);
>>> +
>>> +		__free_one_page(page, pfn, zone, 0, migratetype);
>>> +		unpoisoned = true;
>>> +	}
>>> +	spin_unlock(&zone->lock);
>>> +	return unpoisoned;
>>> +}
>>>  #endif
>>>
>>
>> Though there are multiple page state checks in unpoison_memory() leading
>> upto clearing HWPoison flag, the page must not be in buddy already if
>> __free_one_page() would be called on it.
> 
> Yes, you're right.
> clear_hwpoison_free_buddy_page() is intended to cancel the isolation by
> set_hwpoison_free_buddy_page() which removes the target page from buddy allocator,
> so the page clear_hwpoison_free_buddy_page() tries to handle is not a buddy page
> actually (not linked to any freelist).

Got it. Thanks for the explanation.

      reply	other threads:[~2018-11-14  8:23 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-09  6:47 [PATCH RFC v1 00/11] hwpoison improvement part 1 Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 01/11] mm: hwpoison: cleanup unused PageHuge() check Naoya Horiguchi
2018-11-09  9:52   ` Anshuman Khandual
2018-11-09  6:47 ` [RFC][PATCH v1 02/11] mm: soft-offline: add missing error check of set_hwpoison_free_buddy_page() Naoya Horiguchi
2018-11-09 10:20   ` Anshuman Khandual
2018-11-13  0:16     ` Naoya Horiguchi
2018-11-14  8:53       ` Anshuman Khandual
2018-11-09  6:47 ` [RFC][PATCH v1 03/11] mm: move definition of num_poisoned_pages_inc/dec to include/linux/mm.h Naoya Horiguchi
2018-11-09 10:28   ` Anshuman Khandual
2018-11-13  0:17     ` Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 04/11] mm: madvise: call soft_offline_page() without MF_COUNT_INCREASED Naoya Horiguchi
2018-11-09 10:46   ` Anshuman Khandual
2018-11-13  0:18     ` Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 05/11] mm: hwpoison-inject: don't pin for hwpoison_filter() Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 06/11] mm: hwpoison: remove MF_COUNT_INCREASED Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 07/11] mm: remove flag argument from soft offline functions Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 08/11] mm: soft-offline: isolate error pages from buddy freelist Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 09/11] mm: hwpoison: apply buddy page handling code to hard-offline Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 10/11] mm: clear PageHWPoison in memory hotremove Naoya Horiguchi
2018-11-13  1:32   ` Naoya Horiguchi
2018-11-09  6:47 ` [RFC][PATCH v1 11/11] mm: hwpoison: introduce clear_hwpoison_free_buddy_page() Naoya Horiguchi
2018-11-09 11:33   ` Anshuman Khandual
2018-11-13  0:19     ` Naoya Horiguchi
2018-11-14  8:23       ` Anshuman Khandual [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=b5fb36d0-487c-cf6d-3aa0-a5b43c51b2d6@arm.com \
    --to=anshuman.khandual@arm.com \
    --cc=akpm@linux-foundation.org \
    --cc=ldufour@linux.vnet.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@kernel.org \
    --cc=mike.kravetz@oracle.com \
    --cc=n-horiguchi@ah.jp.nec.com \
    --cc=xishi.qiuxishi@alibaba-inc.com \
    --subject='Re: [RFC][PATCH v1 11/11] mm: hwpoison: introduce clear_hwpoison_free_buddy_page()' \
    /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

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).