lkml.org 
[lkml]   [2008]   [Feb]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] [7/12] GBPAGES: Add an option to disable direct mapping gbpages and a global variable
On Fri,  1 Feb 2008 10:53:20 +0100 (CET) Andi Kleen wrote:

>
> Signed-off-by: Andi Kleen <ak@suse.de>
>
> ---
> Documentation/x86_64/boot-options.txt | 5 +++++
> arch/x86/mm/init_64.c | 16 ++++++++++++++++
> include/asm-x86/pgtable_64.h | 7 +++++++
> 3 files changed, 28 insertions(+)
>
> Index: linux/arch/x86/mm/init_64.c
> ===================================================================
> --- linux.orig/arch/x86/mm/init_64.c
> +++ linux/arch/x86/mm/init_64.c
> @@ -53,6 +53,22 @@ static unsigned long dma_reserve __initd
>
> DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
>
> +enum gbopt direct_gbpages __meminitdata = GBP_DEFAULT;
> +
> +static int __init parse_direct_gbpages(char *arg)
> +{
> + if (!strcmp(arg, "off")) {
> + direct_gbpages = GBP_OFF;
> + return 0;
> + }
> + if (!strcmp(arg, "on")) {
> + direct_gbpages = GBP_ON;
> + return 0;
> + }
> + return -1;
> +}
> +early_param("direct_gbpages", parse_direct_gbpages);
> +
> /*
> * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
> * physical space so we can cache the place of the first one and move
> Index: linux/include/asm-x86/pgtable_64.h
> ===================================================================
> --- linux.orig/include/asm-x86/pgtable_64.h
> +++ linux/include/asm-x86/pgtable_64.h
> @@ -239,6 +239,13 @@ static inline int pud_large(pud_t pte)
>
> #define update_mmu_cache(vma,address,pte) do { } while (0)
>
> +enum gbopt {
> + GBP_OFF = -1,
> + GBP_DEFAULT,
> + GBP_ON
> +};
> +extern enum gbopt direct_gbpages;
> +
> /* Encode and de-code a swap entry */
> #define __swp_type(x) (((x).val >> 1) & 0x3f)
> #define __swp_offset(x) ((x).val >> 8)
> Index: linux/Documentation/x86_64/boot-options.txt
> ===================================================================
> --- linux.orig/Documentation/x86_64/boot-options.txt
> +++ linux/Documentation/x86_64/boot-options.txt
> @@ -307,3 +307,8 @@ Debugging
> stuck (default)
>
> Miscellaneous
> +
> + direct_gbpages=off|on
> + off: Do not use GB pages for kernel direct mapping.
> + on: Use GB pages if hardware supports it, but some heuristic
> + would turn them off.

s/would/could/ ?

---
~Randy

\
 
 \ /
  Last update: 2008-02-05 23:45    [from the cache]
©2003-2011 Jasper Spaans