From: Franck Bui-Huu <fbuihuu@xxxxxxxxx>
Since both kernel and process page tables are never allocated in
highmem these 2 macros were doing unnecessary extra works for getting
a pte from a pmd.
This patch also clean up pte allocation functions by passing
__GFP_ZERO to alloc_pages() and by removing a useless local variable.
With this patch the size of the kernel is slighly reduced.
Signed-off-by: Franck Bui-Huu <fbuihuu@xxxxxxxxx>
---
Hi Ralf,
Maybe I'm missing something but it seems that page tables are
never allocated from highmem. Please correct me if I'm wrong.
This patch boot fine on a 32-bits platform without highmem
though.
This patch does not include any modifications for 64-bits
platforms since I can't test them but this assertion
should be more true since there's no highmem on these
platforms. I can make another patch for such platforms if
you think it makes sense.
Please consider,
Franck
include/asm-mips/pgalloc.h | 22 ++++++----------------
include/asm-mips/pgtable-32.h | 13 +++++--------
2 files changed, 11 insertions(+), 24 deletions(-)
diff --git a/include/asm-mips/pgalloc.h b/include/asm-mips/pgalloc.h
index 5685d4f..a3b9953 100644
--- a/include/asm-mips/pgalloc.h
+++ b/include/asm-mips/pgalloc.h
@@ -62,26 +62,16 @@ static inline void pgd_free(pgd_t *pgd)
free_pages((unsigned long)pgd, PGD_ORDER);
}
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
- unsigned long address)
+static inline pte_t *
+pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
- pte_t *pte;
-
- pte = (pte_t *) __get_free_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, PTE_ORDER);
-
- return pte;
+ return (pte_t *)__get_free_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, PTE_ORDER);
}
-static inline struct page *pte_alloc_one(struct mm_struct *mm,
- unsigned long address)
+static inline struct page *
+pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
- struct page *pte;
-
- pte = alloc_pages(GFP_KERNEL | __GFP_REPEAT, PTE_ORDER);
- if (pte)
- clear_highpage(pte);
-
- return pte;
+ return alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, PTE_ORDER);
}
static inline void pte_free_kernel(pte_t *pte)
diff --git a/include/asm-mips/pgtable-32.h b/include/asm-mips/pgtable-32.h
index 2fbd47e..9e0a8c7 100644
--- a/include/asm-mips/pgtable-32.h
+++ b/include/asm-mips/pgtable-32.h
@@ -143,6 +143,7 @@ pfn_pte(unsigned long pfn, pgprot_t prot)
#define __pgd_offset(address) pgd_index(address)
#define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
#define __pmd_offset(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
+#define __pte_offset(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
/* to find an entry in a kernel page-table-directory */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
@@ -153,19 +154,15 @@ pfn_pte(unsigned long pfn, pgprot_t prot)
#define pgd_offset(mm,addr) ((mm)->pgd + pgd_index(addr))
/* Find an entry in the third-level page table.. */
-#define __pte_offset(address) \
- (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
#define pte_offset(dir, address) \
((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
#define pte_offset_kernel(dir, address) \
((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
-#define pte_offset_map(dir, address) \
- ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
-#define pte_offset_map_nested(dir, address) \
- ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
-#define pte_unmap(pte) ((void)(pte))
-#define pte_unmap_nested(pte) ((void)(pte))
+#define pte_offset_map(dir, address) pte_offset_kernel(dir,address)
+#define pte_offset_map_nested(dir, address) pte_offset_kernel(dir,address)
+#define pte_unmap(pte) ((void)(pte))
+#define pte_unmap_nested(pte) ((void)(pte))
#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
--
1.5.1.3
