[lkml]   [2012]   [Jan]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH 08/17] blkcg: shoot down blkio_groups on elevator switch
    On Mon, Jan 23, 2012 at 10:43:36AM -0800, Tejun Heo wrote:
    > Yeah, this is much more arguable. I don't think it would be too
    > complex to keep per-policy granularity even w/ unified blkg managed by
    > blkcg core (we'll just need to point to separately allocated
    > per-policy data from the unified blkg and clear them selectively).
    > I'm just not convinced of its necessity. With initial config out of
    > the way, elvs and blkcg policies don't get molested all that often.
    > I'll see how complex it actually gets. If it isn't too much
    > complexity, yeah, why not...

    Hmmm... while this isn't terribly complex, it involves considerable
    amount of churn as core layer doesn't currently know what policies are
    bound to which queues how - we'll have to add some part of that before
    shootdown change, use it there, and then later replace it with proper
    per-queue thing. The conversion is already painful enough without
    adding another chunk to juggle around. Given that clearing all on pol
    change isn't too crazy, how about the following?

    * For now, clear unconditionally on pol/elv change.

    * But structure things such that policy specific data are allocated
    separately and on pol/elv change only those policy specific part is

    * Later, if deemed necessary, make the clearing of pol-specific part


     \ /
      Last update: 2012-01-23 20:35    [W:0.020 / U:14.876 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site