lkml.org 
[lkml]   [2011]   [Apr]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 05/18] x86 idle: deprecate "no-hlt" cmdline param
    Date
    From: Len Brown <len.brown@intel.com>

    We'd rather that modern machines not check if HLT works on
    every entry into idle, for the benefit of machines that had
    marginal electricals 15-years ago. If those machines are still running
    the upstream kernel, they can use "idle=poll". The only difference
    will be that they'll now invoke HLT in machine_hlt().

    cc: x86@kernel.org
    Signed-off-by: Len Brown <len.brown@intel.com>
    ---
    Documentation/feature-removal-schedule.txt | 11 +++++++++++
    arch/x86/kernel/cpu/bugs.c | 1 +
    2 files changed, 12 insertions(+), 0 deletions(-)

    diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
    index bab1acb..f587159 100644
    --- a/Documentation/feature-removal-schedule.txt
    +++ b/Documentation/feature-removal-schedule.txt
    @@ -24,6 +24,17 @@ Who: Len Brown <len.brown@intel.com>

    ----------------------------

    +What: x86_32 "no-hlt" cmdline param
    +When: 2.6.40
    +Why: remove a branch from idle path, simplify code used by everybody.
    + This option disabled the use of HLT in idle and machine_halt()
    + for hardware that was flakey 15-years ago. Today we have
    + "idle=poll" that removed HLT from idle, and so if such a machine
    + is still running the upstream kernel, "idle=poll" is likely sufficient.
    +Who: Len Brown <len.brown@intel.com>
    +
    +----------------------------
    +
    What: PRISM54
    When: 2.6.34

    diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
    index c39576c..525514c 100644
    --- a/arch/x86/kernel/cpu/bugs.c
    +++ b/arch/x86/kernel/cpu/bugs.c
    @@ -19,6 +19,7 @@

    static int __init no_halt(char *s)
    {
    + WARN_ONCE(1, "\"no-hlt\" is deprecated, please use \"idle=poll\"\n");
    boot_cpu_data.hlt_works_ok = 0;
    return 1;
    }
    --
    1.7.5.rc0


    \
     
     \ /
      Last update: 2011-04-02 08:27    [from the cache]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and my Meterkast|Read the blog