OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ARM: improve compiler's ability to optimize page tables 

Allow the compiler to better optimize the page table walking code
by avoiding over-complex pmd_addr_end() calculations.  These
calculations prevent the compiler spotting that we'll never iterate
over the PMD table, causing it to create double nested loops where
a single loop will do.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2010-11-21 14:42:47 +00:00
parent 589136bfa7
commit c0ba10b512
1 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/arm/include/asm/pgtable.h
View File

@ -374,6 +374,9 @@ static inline pte_t *pmd_page_vaddr(pmd_t pmd)
#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd)))
/* we don't need complex calculations here as the pmd is folded into the pgd */
#define pmd_addr_end(addr,end) (end)
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.