lkml.org 
[lkml]   [2008]   [Jan]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH] [0/31] Great change_page_attr patch series v2
    Date
    On Tuesday 15 January 2008 10:11:44 Jan Beulich wrote:
    > >>> Andi Kleen <ak@suse.de> 14.01.08 23:16 >>>
    > >
    > >Lots of improvements to change_page_attr(). Make it a lot more
    > >efficient and fix various bugs.
    > >
    > >Changes against earlier version
    > >
    > >- Fixed some checkpatch.pl complaints
    > >- Improved self test suite
    > >- Fixed more reference bugs
    > >- Fix NX handling on 32bit
    > >- Remove some useless code there
    > >- Few other random fixes
    >
    > The one concept that I'm missing (but that I can easily produce a follow-up
    > patch for, as I had this in my c_p_a() changes) is the tracking and adjusting
    > of the reference protection for a large page range that got fully converted
    > to another type (namely relevant for .rodata if it exceeds 2/4 Mb), allowing
    > to use a large page mapping in this case even for non-default mappings.

    Ah -- i got rid of that by changing the rodata code to not do this
    except for the debugging case

    >>
    CPA: Only unmap kernel init pages in text mapping when CONFIG_DEBUG_RODATA is set

    Otherwise the kernel will likely always run with 4K pages instead of 2MB pages,
    which is costly in terms of TLBs.
    <<

    But you're right that would be an useful feature. But wouldn't it require
    aligning rodata to 2MB in the vmlinux to be really effective?

    >
    > Apart from the other comments, the whole series
    >
    > Acked-by: Jan Beulich <jbeulich@novell.com>

    Thanks.

    -Andi





    \
     
     \ /
      Last update: 2008-01-15 11:13    [W:0.032 / U:0.168 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site