From: Christoph Lameter <cl@linux.com>
To: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>,
Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mel@csn.ul.ie>, Wu Fengguang <fengguang.wu@intel.com>,
Jun'ichi Nomura <j-nomura@ce.jp.nec.com>,
linux-mm <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 06/10] hugetlb: move refcounting in hugepage allocation inside hugetlb_lock
Date: Thu, 23 Sep 2010 12:12:55 -0500 (CDT) [thread overview]
Message-ID: <alpine.DEB.2.00.1009231209450.32567@router.home> (raw)
In-Reply-To: <1283908781-13810-7-git-send-email-n-horiguchi@ah.jp.nec.com>
On Wed, 8 Sep 2010, Naoya Horiguchi wrote:
> Currently alloc_huge_page() raises page refcount outside hugetlb_lock.
> but it causes race when dequeue_hwpoison_huge_page() runs concurrently
> with alloc_huge_page().
> To avoid it, this patch moves set_page_refcounted() in hugetlb_lock.
Reviewed-by: Christoph Lameter <cl@linux.com>
One wonders though how many other of these huge races are still there
though.
"Normal" page migration is based on LRU isolation and therefore does not
suffer from these problems on allocation since the page is not yet on the
LRU. Also the LRU isolation is a known issue due to memory reclaim doing
this. This protection is going away of one goes directly to a page
without going through the LRU. That should create more races...
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next prev parent reply other threads:[~2010-09-23 17:12 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-08 1:19 [PATCH 0/10] Hugepage migration (v5) Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 01/10] hugetlb: fix metadata corruption in hugetlb_fault() Naoya Horiguchi
2010-09-20 10:47 ` Mel Gorman
2010-09-22 20:41 ` Christoph Lameter
2010-09-08 1:19 ` [PATCH 02/10] hugetlb: add allocate function for hugepage migration Naoya Horiguchi
2010-09-20 10:59 ` Mel Gorman
2010-09-22 4:41 ` Naoya Horiguchi
2010-09-22 8:37 ` Mel Gorman
2010-09-22 21:05 ` Christoph Lameter
2010-09-23 8:49 ` Mel Gorman
2010-09-23 16:02 ` Christoph Lameter
2010-09-08 1:19 ` [PATCH 03/10] hugetlb: redefine hugepage copy functions Naoya Horiguchi
2010-09-20 11:03 ` Mel Gorman
2010-09-20 11:15 ` Andi Kleen
2010-09-20 11:18 ` Mel Gorman
2010-09-23 16:21 ` Christoph Lameter
2010-09-24 3:24 ` Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 04/10] hugetlb: hugepage migration core Naoya Horiguchi
2010-09-20 11:10 ` Mel Gorman
2010-09-22 4:59 ` Naoya Horiguchi
2010-09-22 8:40 ` Mel Gorman
2010-09-23 16:52 ` Christoph Lameter
2010-09-24 5:58 ` Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 05/10] HWPOISON, hugetlb: add free check to dequeue_hwpoison_huge_page() Naoya Horiguchi
2010-09-23 16:54 ` Christoph Lameter
2010-09-08 1:19 ` [PATCH 06/10] hugetlb: move refcounting in hugepage allocation inside hugetlb_lock Naoya Horiguchi
2010-09-23 17:12 ` Christoph Lameter [this message]
2010-09-24 6:47 ` Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 07/10] HWPOSION, hugetlb: recover from free hugepage error when !MF_COUNT_INCREASED Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 08/10] HWPOISON, hugetlb: soft offlining for hugepage Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 09/10] HWPOISON, hugetlb: fix unpoison " Naoya Horiguchi
2010-09-08 1:19 ` [PATCH 10/10] page-types.c: fix name of unpoison interface Naoya Horiguchi
2010-09-09 10:33 ` [PATCH 0/10] Hugepage migration (v5) Andi Kleen
2010-09-09 22:56 ` Naoya Horiguchi
2010-09-20 11:14 ` Mel Gorman
-- strict thread matches above, loose matches on Subject: below --
2010-09-03 4:37 [PATCH 0/10] Hugepage migration (v4) Naoya Horiguchi
2010-09-03 4:37 ` [PATCH 06/10] hugetlb: move refcounting in hugepage allocation inside hugetlb_lock Naoya Horiguchi
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