lkml.org 
[lkml]   [2008]   [May]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [RFC] x86: xsave/xrstor support, ucontext_t extensions
    On Thu, May 22, 2008 at 07:49:18PM -0700, H. Peter Anvin wrote:
    > Roland McGrath wrote:
    > >>hmm.. so the kernel needs to export all the cpuid info (that the kernel
    > >>enables and supports) to the user through some mechanism then?
    > >
    > >For a cheap interface, we use AT_HWCAP for this. Unfortunately that only
    > >covers the first 32 bits of CPUID info. (For another cheap interface,
    > >giving all the CPUID bits in the vDSO would be easy.)
    > >
    > >For a clunky interface that already exists and is "simple" to use,
    > >there is /dev/cpu/0/cpuid now. I wonder if having a device node and
    > >opening it too much for applications that consider the vDSO too complex.
    >
    > I doubt it.

    Ok. If really needed, they can use this interface aswell. But I don't
    see a need for a new system call / other mechanism, just for xsave
    purpose. They can rely on cpuid or any other equivalent infrastructure the
    kernel provides.

    thanks,
    suresh


    \
     
     \ /
      Last update: 2008-05-23 20:11    [W:0.038 / U:29.964 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site