The patch titled
sparsemem: vmemmap does not need section bits
has been added to the -mm tree. Its filename is
sparsemem-vmemmap-does-not-need-section-bits.patch
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out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: sparsemem: vmemmap does not need section bits
From: Christoph Lameter <clameter@xxxxxxx>
Sparsemem vmemmap does not need any section bits. This patch has the effect
of reducing the number of bits used in page->flags by at least 6.
Signed-off-by: Christoph Lameter <clameter@xxxxxxx>
Cc: Nick Piggin <nickpiggin@xxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Cc: Andy Whitcroft <apw@xxxxxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff -puN include/linux/mm.h~sparsemem-vmemmap-does-not-need-section-bits include/linux/mm.h
--- a/include/linux/mm.h~sparsemem-vmemmap-does-not-need-section-bits
+++ a/include/linux/mm.h
@@ -386,11 +386,11 @@ static inline void set_compound_order(st
* we have run out of space and have to fall back to an
* alternate (slower) way of determining the node.
*
- * No sparsemem: | NODE | ZONE | ... | FLAGS |
- * with space for node: | SECTION | NODE | ZONE | ... | FLAGS |
- * no space for node: | SECTION | ZONE | ... | FLAGS |
+ * No sparsemem or sparsemem vmemmap: | NODE | ZONE | ... | FLAGS |
+ * classic sparse with space for node:| SECTION | NODE | ZONE | ... | FLAGS |
+ * classic sparse no space for node: | SECTION | ZONE | ... | FLAGS |
*/
-#ifdef CONFIG_SPARSEMEM
+#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
#define SECTIONS_WIDTH SECTIONS_SHIFT
#else
#define SECTIONS_WIDTH 0
@@ -401,6 +401,9 @@ static inline void set_compound_order(st
#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= FLAGS_RESERVED
#define NODES_WIDTH NODES_SHIFT
#else
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+#error "Vmemmap: No space for nodes field in page flags"
+#endif
#define NODES_WIDTH 0
#endif
@@ -493,10 +496,12 @@ static inline struct zone *page_zone(str
return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
}
+#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
static inline unsigned long page_to_section(struct page *page)
{
return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
}
+#endif
static inline void set_page_zone(struct page *page, enum zone_type zone)
{
_
Patches currently in -mm which might be from clameter@xxxxxxx are
fix-mempolicy-reference-counting-bugs.patch
git-unionfs.patch
git-slub.patch
slab-pass-correct-flags-to-kmem_getpages.patch
ntfs-fix-nommu-build.patch
x86-cast-cmpxchg-and-cmpxchg_local-result-for-386-and-486.patch
remove-set_migrateflags.patch
mm-use-zonelists-instead-of-zones-when-direct-reclaiming-pages.patch
mm-introduce-node_zonelist-for-accessing-the-zonelist-for-a-gfp-mask.patch
mm-remember-what-the-preferred-zone-is-for-zone_statistics.patch
mm-use-two-zonelist-that-are-filtered-by-gfp-mask.patch
mm-have-zonelist-contains-structs-with-both-a-zone-pointer-and-zone_idx.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask-doc-fixes.patch
mm-filter-based-on-a-nodemask-as-well-as-a-gfp_mask-make-dequeue_huge_page_vma-obey-mpol_bind-nodemask.patch
mm-move-cache_line_size-to-linux-cacheh.patch
mempolicy-convert-mpol-constants-to-enum.patch
mempolicy-support-optional-mode-flags.patch
mempolicy-add-mpol_f_static_nodes-flag.patch
mempolicy-add-bitmap_onto-and-bitmap_fold-operations.patch
mempolicy-add-mpol_f_relative_nodes-flag.patch
mempolicy-update-numa-memory-policy-documentation.patch
sparsemem-vmemmap-does-not-need-section-bits.patch
kbuild-create-a-way-to-create-preprocessor-constants-from-c-expressions.patch
pageflags-use-an-enum-for-the-flags.patch
pageflags-get-rid-of-flags_reserved.patch
pageflags-introduce-macros-to-generate-page-flag-functions.patch
pageflags-convert-to-the-use-of-new-macros.patch
pageflags-use-proper-page-flag-functions-in-xen.patch
pageflags-eliminate-pg_xxx-aliases.patch
reiser4.patch
reiser4-portion-of-zero_user-cleanup-patch.patch
page-owner-tracking-leak-detector.patch
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