lkml.org 
[lkml]   [2008]   [Jan]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] [9/9] GBPAGES: Do kernel direct mapping at boot using GB pages
    On Thu, Jan 31, 2008 at 05:17:41PM +0100, Thomas Gleixner wrote:
    > On Tue, 29 Jan 2008, Andi Kleen wrote:
    > >
    > > +static unsigned long direct_entry(unsigned long paddr)
    >
    > Please use a more sensible function name. This one has no association
    > with the functionality at all.

    Can you suggest one? I honestly cannot think of a better one.
    Its's a "entry" in the "direct" mapping.

    > > + if (direct_gbpages >= 0 && cpu_has_gbpages) {
    > > + printk(KERN_INFO "Using GB pages for direct mapping\n");
    > > + direct_gbpages = 1;
    > > + } else
    > > + direct_gbpages = 0;
    > > +}
    >
    > Please use simple boolean logic. gbpages are either enabled or disabled.

    It's a fairly standard widely used idiom for command line options because
    it allows default and forcing. e.g. there can be cases when the kernel
    disables it, but then it makes sense for the command line option
    to override it. There is already one case in the kernel that
    disables it.

    > > * prefetches from the CPU leading to inconsistent cache lines.
    > > @@ -467,6 +511,8 @@ __clear_kernel_mapping(unsigned long add
    > > continue;
    > >
    > > pud = pud_offset(pgd, address);
    > > + if (pud_large(*pud))
    > > + split_gb_page(pud, __pa(address));
    > > if (pud_none(*pud))
    > > continue;
    >
    > As I said before, this needs to use CPA and not implement another variant.

    Ok, I can switch GART over to CPA, but that will make the patch
    much more intrusive and a little riskier. Is that ok for you
    and will it be still considered .25 candidate?

    -Andi


    \
     
     \ /
      Last update: 2008-01-31 17:41    [W:2.742 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site