unimore/kernel-hacking-2024-linux-steffo
unimore/kernel-hacking-2024-linux-steffo
1
Fork 0
Code Pull requests 5 Wiki Activity

x86: find_early_table_space() unification

Browse source 
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: Pekka 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: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Pekka Enberg 2009-03-05 14:54:54 +02:00 committed by Ingo Molnar
parent 4bbd4fa038
commit 49a2bf7303
2 changed files with 23 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
arch/x86/mm/init_32.c
View file

@ -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");

14
arch/x86/mm/init_64.c
View file

@ -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");