2008-10-31 09:44:58

by Zhao Lei

Subject: [PATCH] Avoid duplicate running of pud_offset and pmd_offset in one_md_table_init()

If !(pgd_val(*pgd) & _PAGE_PRESENT) in PAE mode, we need not get value of
pmd_table again.

Signed-off-by: Zhao Lei <[email protected]>
---
arch/x86/mm/init_32.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 8396868..7f8a2da 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -102,6 +102,8 @@ static pmd_t * __init one_md_table_init(pgd_t *pgd)
set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT));
pud = pud_offset(pgd, 0);
BUG_ON(pmd_table != pmd_offset(pud, 0));
+
+ return pmd_table;
}
#endif
pud = pud_offset(pgd, 0);
--
1.5.5.3

2008-10-31 10:04:25

by Ingo Molnar

Subject: Re: [PATCH] Avoid duplicate running of pud_offset and pmd_offset in one_md_table_init()

* Zhaolei <[email protected]> wrote:

> If !(pgd_val(*pgd) & _PAGE_PRESENT) in PAE mode, we need not get value of
> pmd_table again.
>
> Signed-off-by: Zhao Lei <[email protected]>
> ---
> arch/x86/mm/init_32.c | 2 ++
> 1 files changed, 2 insertions(+), 0 deletions(-)

applied to tip/x86/cleanups, thanks!

Ingo