lkml.org 
[lkml]   [2006]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [RFC][WIP] DIO simplification and AIO-DIO stability
    On Thu, Feb 23, 2006 at 08:01:32PM -0500, Chris Mason wrote:
    > On Thursday 23 February 2006 02:29, Suparna Bhattacharya wrote:
    > > DIO code complexity and stability concerns were discussed way back during
    > > OLS and Kernel summit last year. Still, the lack of a solid alternative and
    > > motivation to subject oneself to the test of courage and delicate balance
    > > that fiddling with this code entails, has meant that gingerly applying
    > > fixes and bandaids as and when bugs are found, and moving on thereafter,
    > > continues to be the most palatable option.
    > >
    > > A recent AIO-DIO bug reported by Kenneth Chen, came very close
    > > to being the proverbial last straw for me. Hence, here is a rough attempt
    > > to put together a (currently WIP) draft towards DIO code simplication,
    > > based on suggestions that some of you have brought up at various times.
    > > Several details, e.g. range locking implementation still need to be fleshed
    > > out completely, ideas/comments/suggestions would be welcome.
    >
    > I'm really in favor of this, and had actually started an implementation a
    > while back. At the time, I posted a different version that added yet another
    > semaphore but simplified the rest of the locking (and held no locks during
    > the dio/aio).

    Yes I have saved that patch as a reference as well.
    With range locking I'm hoping that would be able to avoid the need for
    i_hole_sem. Also I wanted to push out all locking code out of the DIO
    code to avoid the various locking mode checks.

    >
    > I'll try to dig up my original radix tagging code. I'm not sure if I kept it,
    > but it did pass Daniel's dio vs buffer io racing tests at the time.

    Cool - that would be great !

    Regards
    Suparna

    >
    > -chris
    >
    > --
    > To unsubscribe, send a message with 'unsubscribe linux-aio' in
    > the body to majordomo@kvack.org. For more info on Linux AIO,
    > see: http://www.kvack.org/aio/
    > Don't email: <a href=mailto:"aart@kvack.org">aart@kvack.org</a>

    --
    Suparna Bhattacharya (suparna@in.ibm.com)
    Linux Technology Center
    IBM Software Lab, India

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2006-02-24 10:40    [W:4.024 / U:0.548 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site