mm: move highest_memmap_pfn

Move highest_memmap_pfn __read_mostly from page_alloc.c next to zero_pfn __read_mostly in memory.c: to help them share a cacheline, since they're very often tested together in vm_normal_page(). Signed-off-by: Hugh Dickins <[email protected]> Cc: Rik van Riel <[email protected]> Cc: KAMEZAWA Hiroyuki <[email protected]> Cc: KOSAKI Motohiro <[email protected]> Cc: Nick Piggin <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Minchan Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
iegor · Sep 22, 2009 · 03f6462 · 03f6462
1 parent 62eede6
commit 03f6462
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Showing 3 changed files with 3 additions and 2 deletions.
diff --git a/mm/internal.h b/mm/internal.h
@@ -37,6 +37,8 @@ static inline void __put_page(struct page *page)
 	atomic_dec(&page->_count);
 }
 
+extern unsigned long highest_memmap_pfn;
+
 /*
  * in mm/vmscan.c:
  */
@@ -46,7 +48,6 @@ extern void putback_lru_page(struct page *page);
 /*
  * in mm/page_alloc.c
  */
-extern unsigned long highest_memmap_pfn;
 extern void __free_pages_bootmem(struct page *page, unsigned int order);
 extern void prep_compound_page(struct page *page, unsigned long order);
 

diff --git a/mm/memory.c b/mm/memory.c
@@ -109,6 +109,7 @@ static int __init disable_randmaps(char *s)
 __setup("norandmaps", disable_randmaps);
 
 unsigned long zero_pfn __read_mostly;
+unsigned long highest_memmap_pfn __read_mostly;
 
 /*
  * CONFIG_MMU architectures set up ZERO_PAGE in their paging_init()

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
@@ -72,7 +72,6 @@ EXPORT_SYMBOL(node_states);
 
 unsigned long totalram_pages __read_mostly;
 unsigned long totalreserve_pages __read_mostly;
-unsigned long highest_memmap_pfn __read_mostly;
 int percpu_pagelist_fraction;
 gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;