From: Mel Gorman <mgorman@suse.de>
To: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>, Linux-MM <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 14/15] mm: numa: Flush TLB if NUMA hinting faults race with PTE scan update
Date: Tue, 3 Dec 2013 23:46:37 +0000 [thread overview]
Message-ID: <20131203234637.GS11295@suse.de> (raw)
In-Reply-To: <529E641A.7040804@redhat.com>
On Tue, Dec 03, 2013 at 06:07:06PM -0500, Rik van Riel wrote:
> On 12/03/2013 03:52 AM, Mel Gorman wrote:
> > NUMA PTE updates and NUMA PTE hinting faults can race against each other. The
> > setting of the NUMA bit defers the TLB flush to reduce overhead. NUMA
> > hinting faults do not flush the TLB as X86 at least does not cache TLB
> > entries for !present PTEs. However, in the event that the two race a NUMA
> > hinting fault may return with the TLB in an inconsistent state between
> > different processors. This patch detects potential for races between the
> > NUMA PTE scanner and fault handler and will flush the TLB for the affected
> > range if there is a race.
> >
> > Signed-off-by: Mel Gorman <mgorman@suse.de>
>
> > diff --git a/mm/migrate.c b/mm/migrate.c
> > index 5dfd552..ccc814b 100644
> > --- a/mm/migrate.c
> > +++ b/mm/migrate.c
> > @@ -1662,6 +1662,39 @@ void wait_migrate_huge_page(struct anon_vma *anon_vma, pmd_t *pmd)
> > smp_rmb();
> > }
> >
> > +unsigned long numa_fault_prepare(struct mm_struct *mm)
> > +{
> > + /* Paired with task_numa_work */
> > + smp_rmb();
> > + return mm->numa_next_reset;
> > +}
>
> The patch that introduces mm->numa_next_reset, and the
> patch that increments it, seem to be missing from your
> series...
>
Damn. s/numa_next_reset/numa_next_scan/ in that patch
--
Mel Gorman
SUSE Labs
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next prev parent reply other threads:[~2013-12-03 23:46 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-03 8:51 [PATCH 00/14] NUMA balancing segmentation faults candidate fix on large machines Mel Gorman
2013-12-03 8:51 ` [PATCH 01/15] mm: numa: Do not batch handle PMD pages Mel Gorman
2013-12-03 8:51 ` [PATCH 02/15] mm: hugetlbfs: fix hugetlbfs optimization Mel Gorman
2013-12-03 8:51 ` [PATCH 03/15] mm: thp: give transparent hugepage code a separate copy_page Mel Gorman
2013-12-04 16:59 ` Alex Thorlton
2013-12-05 13:35 ` Mel Gorman
2013-12-03 8:51 ` [PATCH 04/15] mm: numa: Serialise parallel get_user_page against THP migration Mel Gorman
2013-12-03 23:07 ` Rik van Riel
2013-12-03 23:54 ` Mel Gorman
2013-12-03 8:51 ` [PATCH 05/15] mm: numa: Call MMU notifiers on " Mel Gorman
2013-12-03 8:51 ` [PATCH 06/15] mm: Clear pmd_numa before invalidating Mel Gorman
2013-12-03 8:51 ` [PATCH 07/15] mm: numa: Do not clear PMD during PTE update scan Mel Gorman
2013-12-03 8:51 ` [PATCH 08/15] mm: numa: Do not clear PTE for pte_numa update Mel Gorman
2013-12-03 8:51 ` [PATCH 09/15] mm: numa: Ensure anon_vma is locked to prevent parallel THP splits Mel Gorman
2013-12-03 8:51 ` [PATCH 10/15] mm: numa: Avoid unnecessary work on the failure path Mel Gorman
2013-12-03 8:51 ` [PATCH 11/15] sched: numa: Skip inaccessible VMAs Mel Gorman
2013-12-03 8:51 ` [PATCH 12/15] Clear numa on mprotect Mel Gorman
2013-12-03 8:52 ` [PATCH 13/15] mm: numa: Avoid unnecessary disruption of NUMA hinting during migration Mel Gorman
2013-12-03 8:52 ` [PATCH 14/15] mm: numa: Flush TLB if NUMA hinting faults race with PTE scan update Mel Gorman
2013-12-03 23:07 ` Rik van Riel
2013-12-03 23:46 ` Mel Gorman [this message]
2013-12-04 14:33 ` Rik van Riel
2013-12-04 16:07 ` Mel Gorman
2013-12-05 15:40 ` Rik van Riel
2013-12-05 19:54 ` Mel Gorman
2013-12-05 20:05 ` Rik van Riel
2013-12-06 9:24 ` Mel Gorman
2013-12-06 17:38 ` Alex Thorlton
2013-12-06 18:32 ` Mel Gorman
2013-12-06 19:13 ` [PATCH 14/15] mm: fix TLB flush race between migration, and change_protection_range Rik van Riel
2013-12-06 20:32 ` Christoph Lameter
2013-12-06 21:21 ` Rik van Riel
2013-12-07 0:25 ` Christoph Lameter
2013-12-07 3:14 ` Rik van Riel
2013-12-09 16:00 ` Christoph Lameter
2013-12-09 16:27 ` Mel Gorman
2013-12-09 16:59 ` Christoph Lameter
2013-12-09 21:01 ` Rik van Riel
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