mm: numa: defer TLB flush for THP migration as long as possible

THP migration can fail for a variety of reasons.  Avoid flushing the TLB
to deal with THP migration races until the copy is ready to start.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mel Gorman 2013-12-18 17:08:46 -08:00 committed by Linus Torvalds
parent af2c1401e6
commit b0943d61b8
2 changed files with 3 additions and 7 deletions

View File

@ -1376,13 +1376,6 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
goto clear_pmdnuma;
}
/*
* The page_table_lock above provides a memory barrier
* with change_protection_range.
*/
if (mm_tlb_flush_pending(mm))
flush_tlb_range(vma, haddr, haddr + HPAGE_PMD_SIZE);
/*
* Migrate the THP to the requested node, returns with page unlocked
* and pmd_numa cleared.

View File

@ -1759,6 +1759,9 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
goto out_fail;
}
if (mm_tlb_flush_pending(mm))
flush_tlb_range(vma, mmun_start, mmun_end);
/* Prepare a page as a migration target */
__set_page_locked(new_page);
SetPageSwapBacked(new_page);