Re: [PATCH] x86: mtrr cleanup for converting continuous to discrete layout v5

[Randy Dunlap <randy.dunlap@oracle.com>]

On Mon, 28 Apr 2008 15:05:05 -0700 Yinghai Lu wrote:

> Index: linux-2.6/Documentation/kernel-parameters.txt
> ===================================================================
> --- linux-2.6.orig/Documentation/kernel-parameters.txt
> +++ linux-2.6/Documentation/kernel-parameters.txt
> @@ -595,6 +595,16 @@ and is between 256 and 4096 characters. 
>  			See drivers/char/README.epca and
>  			Documentation/digiepca.txt.
>  
> +	disable_mtrr_cleanup [X86]
> +	enable_mtrr_cleanup [X86]
> +			The kernel try to adjust MTRR layout from continuous

                                   tries

> +			to discrete, to make x server driver could add WB entry

                                             X server driver able to add WB entry

> +			later. This parameter enable/disable that.

                                              enables/disables

> +
> +	mtrr_chunk_size=nn[KMG] [X86]
> +			used for mtrr cleanup. It is largest continous chunk
> +			that could hold holes aka. UC entries.
> +
>  	disable_mtrr_trim [X86, Intel and AMD only]
>  			By default the kernel will trim any uncacheable
>  			memory out of your available memory pool based on
> Index: linux-2.6/arch/x86/Kconfig
> ===================================================================
> --- linux-2.6.orig/arch/x86/Kconfig
> +++ linux-2.6/arch/x86/Kconfig
> @@ -1035,6 +1035,32 @@ config MTRR
>  
>  	  See <file:Documentation/mtrr.txt> for more information.
>  
> +config MTRR_SANITIZER
> +	def_bool y
> +	prompt "MTRR cleanup support"
> +	depends on MTRR
> +	help
> +	  Convert MTRR layout from continuous to discrete, so some X driver
> +	  could add WB entries.
> +
> +	  Say N here if you see bootup problems (boot crash, boot hang,
> +	  spontaneous reboots).
> +
> +	  could be disabled with disable_mtrr_cleanup. also mtrr_chunk_size

          Could                                        Also

> +	  could be used to send largest mtrr entry size for continuous block
> +	  to hold holes (aka. UC entries)
> +
> +	  If unsure, say Y.
> +
> +config MTRR_SANITIZER_ENABLE_DEFAULT
> +	bool
> +	prompt "MTRR cleanup enable default"

	prompt "Enable MTRR cleanup"
or
	prompt "Enable MTRR cleanup by default"

> +	depends on MTRR_SANITIZER
> +	help
> +	  Enable mtrr cleanup by default

                                 default.

> +
> +	  If unsure, say Y.
> +
>  config X86_PAT
>  	bool
>  	prompt "x86 PAT support"

---
~Randy