From 00d1c5e05736f947687be27706bda01cec104e57 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 17 Apr 2008 17:40:45 +0200 Subject: x86: add gbpages switches These new controls toggle experimental support for a new CPU feature, the straightforward extension of largepages from the pmd level to the pud level, which allows 1GB (kernel) TLBs instead of 2MB TLBs. Turn it off by default, as this code has not been tested well enough yet. Use the CONFIG_DIRECT_GBPAGES=y .config option or gbpages on the boot line can be used to enable it. If enabled in the .config then nogbpages boot option disables it. Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- include/asm-x86/pgtable_64.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/asm-x86/pgtable_64.h') diff --git a/include/asm-x86/pgtable_64.h b/include/asm-x86/pgtable_64.h index 01d2359e7a3..6ef09914acb 100644 --- a/include/asm-x86/pgtable_64.h +++ b/include/asm-x86/pgtable_64.h @@ -239,6 +239,8 @@ static inline int pud_large(pud_t pte) #define update_mmu_cache(vma,address,pte) do { } while (0) +extern int direct_gbpages; + /* Encode and de-code a swap entry */ #define __swp_type(x) (((x).val >> 1) & 0x3f) #define __swp_offset(x) ((x).val >> 8) -- cgit v1.2.3