Subject: Re: [PATCH V4 0/2] mm: FAULT_AROUND_ORDER patchset performance data for powerpc

From: Madhavan Srinivasan <[email-masked]>
Date: Thu, 15 May 2014 13:55:11 +0530

Hi Ingo,

	Do you have any comments for the latest version of the patchset. If
not, kindly can you pick it up as is.

With regards
Maddy

> Kirill A. Shutemov with 8c6e50b029 commit introduced
> vm_ops->map_pages() for mapping easy accessible pages around
> fault address in hope to reduce number of minor page faults.
> 
> This patch creates infrastructure to modify the FAULT_AROUND_ORDER
> value using mm/Kconfig. This will enable architecture maintainers
> to decide on suitable FAULT_AROUND_ORDER value based on
> performance data for that architecture. First patch also defaults
> FAULT_AROUND_ORDER Kconfig element to 4. Second patch list
> out the performance numbers for powerpc (platform pseries) and
> initialize the fault around order variable for pseries platform of
> powerpc.
> 
> V4 Changes:
>   Replaced the BUILD_BUG_ON with VM_BUG_ON.
>   Moved fault_around_pages() and fault_around_mask() functions outside of
>    #ifdef CONFIG_DEBUG_FS.
> 
> V3 Changes:
>   Replaced FAULT_AROUND_ORDER macro to a variable to support arch's that
>    supports sub platforms.
>   Made changes in commit messages.
> 
> V2 Changes:
>   Created Kconfig parameter for FAULT_AROUND_ORDER
>   Added check in do_read_fault to handle FAULT_AROUND_ORDER value of 0
>   Made changes in commit messages.
> 
> Madhavan Srinivasan (2):
>   mm: move FAULT_AROUND_ORDER to arch/
>   powerpc/pseries: init fault_around_order for pseries
> 
>  arch/powerpc/platforms/pseries/pseries.h |    2 ++
>  arch/powerpc/platforms/pseries/setup.c   |    5 +++++
>  mm/Kconfig                               |    8 ++++++++
>  mm/memory.c                              |   25 ++++++-------------------
>  4 files changed, 21 insertions(+), 19 deletions(-)
>