All of lore.kernel.org
 help / color / mirror / Atom feed
From: Xishi Qiu <qiuxishi@huawei.com>
To: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: zhong jiang <zhongjiang@huawei.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Vlastimil Babka <vbabka@suse.cz>, Aaron Lu <aaron.lu@intel.com>,
	Mel Gorman <mgorman@suse.de>, Rik van Riel <riel@redhat.com>,
	David Rientjes <rientjes@google.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Linux Memory Management List <linux-mm@kvack.org>
Subject: Re: [PATCH v2 3/3] mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
Date: Mon, 15 Feb 2016 18:06:08 +0800	[thread overview]
Message-ID: <56C1A310.9090305@huawei.com> (raw)
In-Reply-To: <20160215024220.GA30918@js1304-P5Q-DELUXE>

On 2016/2/15 10:42, Joonsoo Kim wrote:

>>
>> I have a question about the zone continuity. because hole exists at
>> arbitrary position in a page block. Therefore, only pageblock_pf_to_page()
>> is insufficiency, whether pageblock aligned pfn or not , the pfn_valid_within()
>> is necessary.
>>
>> eh: 120M-122M is a range of page block, but the 120.5M-121.5M is holes, only by
>> pageblock_pfn_to_page() to conclude in the result is inaccurate
> 
> contiguous may be misleading word. It doesn't represent there are no
> hole. It only represents that all pageblocks within zone span belong to
> corresponding zone and validity of all pageblock aligned pfn is
> checked. So, if it is set, we can safely call pfn_to_page() for pageblock
> aligned pfn in that zone without checking pfn_valid().
> 
> Thanks.
> 

Hi Joonsoo,

So "contiguous" here only means that struct page is exist, and don't care whether
the memory is exist, right?

Thanks,
Xishi Qiu

> 
> .
> 

WARNING: multiple messages have this Message-ID (diff)
From: Xishi Qiu <qiuxishi@huawei.com>
To: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: zhong jiang <zhongjiang@huawei.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Vlastimil Babka <vbabka@suse.cz>, Aaron Lu <aaron.lu@intel.com>,
	Mel Gorman <mgorman@suse.de>, Rik van Riel <riel@redhat.com>,
	David Rientjes <rientjes@google.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Linux Memory Management List <linux-mm@kvack.org>
Subject: Re: [PATCH v2 3/3] mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
Date: Mon, 15 Feb 2016 18:06:08 +0800	[thread overview]
Message-ID: <56C1A310.9090305@huawei.com> (raw)
In-Reply-To: <20160215024220.GA30918@js1304-P5Q-DELUXE>

On 2016/2/15 10:42, Joonsoo Kim wrote:

>>
>> I have a question about the zone continuity. because hole exists at
>> arbitrary position in a page block. Therefore, only pageblock_pf_to_page()
>> is insufficiency, whether pageblock aligned pfn or not , the pfn_valid_within()
>> is necessary.
>>
>> eh: 120M-122M is a range of page block, but the 120.5M-121.5M is holes, only by
>> pageblock_pfn_to_page() to conclude in the result is inaccurate
> 
> contiguous may be misleading word. It doesn't represent there are no
> hole. It only represents that all pageblocks within zone span belong to
> corresponding zone and validity of all pageblock aligned pfn is
> checked. So, if it is set, we can safely call pfn_to_page() for pageblock
> aligned pfn in that zone without checking pfn_valid().
> 
> Thanks.
> 

Hi Joonsoo,

So "contiguous" here only means that struct page is exist, and don't care whether
the memory is exist, right?

Thanks,
Xishi Qiu

> 
> .
> 



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2016-02-15 10:06 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-04  6:19 [PATCH v2 1/3] mm/compaction: fix invalid free_pfn and compact_cached_free_pfn Joonsoo Kim
2016-02-04  6:19 ` Joonsoo Kim
2016-02-04  6:19 ` [PATCH v2 2/3] mm/compaction: pass only pageblock aligned range to pageblock_pfn_to_page Joonsoo Kim
2016-02-04  6:19   ` Joonsoo Kim
2016-02-10 12:52   ` Vlastimil Babka
2016-02-10 12:52     ` Vlastimil Babka
2016-02-04  6:19 ` [PATCH v2 3/3] mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous Joonsoo Kim
2016-02-04  6:19   ` Joonsoo Kim
2016-02-05  0:49   ` Andrew Morton
2016-02-05  0:49     ` Andrew Morton
2016-02-05 16:11     ` Joonsoo Kim
2016-02-05 16:11       ` Joonsoo Kim
2016-02-09 17:58       ` Vlastimil Babka
2016-02-09 17:58         ` Vlastimil Babka
2016-02-09 20:53         ` Andrew Morton
2016-02-09 20:53           ` Andrew Morton
2016-02-10 13:42           ` Vlastimil Babka
2016-02-10 13:42             ` Vlastimil Babka
2016-02-10 18:58             ` Andrew Morton
2016-02-10 18:58               ` Andrew Morton
2016-02-11  1:58               ` Joonsoo Kim
2016-02-11  1:58                 ` Joonsoo Kim
2016-02-14 10:21       ` zhong jiang
2016-02-14 10:21         ` zhong jiang
2016-02-15  2:42         ` Joonsoo Kim
2016-02-15  2:42           ` Joonsoo Kim
2016-02-15 10:06           ` Xishi Qiu [this message]
2016-02-15 10:06             ` Xishi Qiu
2016-02-15 14:24             ` Joonsoo Kim
2016-02-15 14:24               ` Joonsoo Kim

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=56C1A310.9090305@huawei.com \
    --to=qiuxishi@huawei.com \
    --cc=aaron.lu@intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=iamjoonsoo.kim@lge.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=riel@redhat.com \
    --cc=rientjes@google.com \
    --cc=vbabka@suse.cz \
    --cc=zhongjiang@huawei.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.