Commit 49a2bf73 authored by Pekka Enberg's avatar Pekka Enberg Committed by Ingo Molnar
Browse files

x86: find_early_table_space() unification 



Impact: cleanup

There are some minor differences between the 32-bit and 64-bit
find_early_table_space() functions. This patch wraps those
differences under CONFIG_X86_32 to make the function identical
on both configurations.

Signed-off-by: default avatarPekka Enberg <penberg@cs.helsinki.fi>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236257708-27269-3-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 4bbd4fa0

arch/x86/mm/init_32.c

+9 −0
Original line number Diff line number Diff line
@@ -855,24 +855,33 @@ static void __init find_early_table_space(unsigned long end, int use_pse, 
		unsigned long extra;



		extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);

#ifdef CONFIG_X86_32

		extra += PMD_SIZE;

#endif

		ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;

	} else

		ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;



	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);



#ifdef CONFIG_X86_32

	/* for fixmap */

	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);

#endif



	/*

	 * RED-PEN putting page tables only on node 0 could

	 * cause a hotspot and fill up ZONE_DMA. The page tables

	 * need roughly 0.5KB per GB.

	 */

#ifdef CONFIG_X86_32

	start = 0x7000;

	table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,

					tables, PAGE_SIZE);

#else /* CONFIG_X86_64 */

	start = 0x8000;

	table_start = find_e820_area(start, end, tables, PAGE_SIZE);

#endif

	if (table_start == -1UL)

		panic("Cannot find space for the kernel page tables");

arch/x86/mm/init_64.c

+14 −0
Original line number Diff line number Diff line
@@ -569,19 +569,33 @@ static void __init find_early_table_space(unsigned long end, int use_pse, 
		unsigned long extra;



		extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);

#ifdef CONFIG_X86_32

		extra += PMD_SIZE;

#endif

		ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;

	} else

		ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;



	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);



#ifdef CONFIG_X86_32

	/* for fixmap */

	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);

#endif



	/*

	 * RED-PEN putting page tables only on node 0 could

	 * cause a hotspot and fill up ZONE_DMA. The page tables

	 * need roughly 0.5KB per GB.

	 */

#ifdef CONFIG_X86_32

	start = 0x7000;

	table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,

					tables, PAGE_SIZE);

#else /* CONFIG_X86_64 */

	start = 0x8000;

	table_start = find_e820_area(start, end, tables, PAGE_SIZE);

#endif

	if (table_start == -1UL)

		panic("Cannot find space for the kernel page tables");

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