lkml.org 
[lkml]   [2012]   [Feb]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] ARM: cache-v7: Disable preemption when reading CCSIDR
    On 02/02/12 13:38, Nicolas Pitre wrote:
    > On Thu, 2 Feb 2012, Russell King - ARM Linux wrote
    >> On Thu, Feb 02, 2012 at 11:24:46AM -0800, Stephen Boyd wrote:
    >>> Should we move get_thread_info into assembler.h? It seems odd
    >>> to include entry-header.S but I saw that vfp was doing the same.
    >> Probably yes, and probably also have preempt_disable and preempt_enable
    >> assembler macros. That's going to get rather icky if we have to
    >> explicitly call the scheduler though (to solve (1)).
    > What about a pair of helpers written in C instead?
    >
    > v7_flush_dcache_all() could be renamed, and a wrapper function called
    > v7_flush_dcache_all() would call the preemption disable helper, call the
    > former v7_flush_dcache_all code, then call the preemption enable helper.
    >
    > Then __v7_setup() could still call the core cache flush code without
    > issues.

    I tried to put the preemption disable/enable right around the place
    where it was needed. With this approach we would disable preemption
    during the entire cache flush. I'm not sure if we want to make this
    function worse for performance, do we? It certainly sounds easier than
    writing all the preempt macros in assembly though.

    --
    Sent by an employee of the Qualcomm Innovation Center, Inc.
    The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.



    \
     
     \ /
      Last update: 2012-02-03 00:39    [W:0.022 / U:62.676 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site