Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1157890

[PATCHv6 08/36] khugepaged: ignore pmd tables with THP mapped with ptes

From "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Newsgroups linux.kernel
Subject [PATCHv6 08/36] khugepaged: ignore pmd tables with THP mapped with ptes
Date 2015-06-03 19:20 +0200
Message-ID <pxkuB-7Ey-7@gated-at.bofh.it> (permalink)
References <pxkkW-7sr-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


Prepare khugepaged to see compound pages mapped with pte. For now we
won't collapse the pmd table with such pte.

khugepaged is subject for future rework wrt new refcounting.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
---
 mm/huge_memory.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 4ad975506c1b..a5423bee0109 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2680,6 +2680,11 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
 		page = vm_normal_page(vma, _address, pteval);
 		if (unlikely(!page))
 			goto out_unmap;
+
+		/* TODO: teach khugepaged to collapse THP mapped with pte */
+		if (PageCompound(page))
+			goto out_unmap;
+
 		/*
 		 * Record which node the original page is from and save this
 		 * information to khugepaged_node_load[].
@@ -2690,7 +2695,6 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
 		if (khugepaged_scan_abort(node))
 			goto out_unmap;
 		khugepaged_node_load[node]++;
-		VM_BUG_ON_PAGE(PageCompound(page), page);
 		if (!PageLRU(page) || PageLocked(page) || !PageAnon(page))
 			goto out_unmap;
 		/*
-- 
2.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCHv6 00/36] THP refcounting redesign "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:10 +0200
  [PATCHv6 12/36] thp: drop all split_huge_page()-related code "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:10 +0200
  [PATCHv6 18/36] arm, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:10 +0200
  [PATCHv6 01/36] mm, proc: adjust PSS calculation "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:10 +0200
  [PATCHv6 28/36] mm, numa: skip PTE-mapped THP on numa fault "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:10 +0200
  [PATCHv6 02/36] rmap: add argument to charge compound page "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:10 +0200
  [PATCHv6 24/36] x86, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 08/36] khugepaged: ignore pmd tables with THP mapped with ptes "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 19/36] mips, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 33/36] migrate_pages: try to split pages on qeueuing "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 13/36] mm: drop tail page refcounting "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 27/36] mm: differentiate page_mapped() from page_mapcount() for compound pages "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 32/36] thp: reintroduce split_huge_page() "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 21/36] s390, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 29/36] thp: implement split_huge_pmd() "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 20/36] powerpc, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 17/36] arm64, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 34/36] thp: introduce deferred_split_huge_page() "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 30/36] thp: add option to setup migration entiries during PMD split "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 10/36] mm, vmstats: new THP splitting event "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 23/36] tile, thp: remove infrastructure for handling splitting PMDs "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 06/36] mm: handle PTE-mapped tail pages in gerneric fast gup implementaiton "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 31/36] thp, mm: split_huge_page(): caller need to lock page "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 35/36] mm: re-enable THP "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200
  [PATCHv6 16/36] mm, thp: remove compound_lock "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> - 2015-06-03 19:20 +0200

csiph-web