lkml.org 
[lkml]   [2008]   [Jan]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    Subject[RFC][PATCH 0/2] hrtimer breakage
    Hi,

    If you're in the To: field, I broke your arch with (post .24) commit:
    d3d74453c34f8fd87674a8cf5b8a327c68f22e99

    So, to be clear, that broke:
    alpha, arm, blackfin, frv, m68knommu, sh, sh64 and sparc

    The deadlock resulting was found by Russell:

    IRQ handle
    -> timer_tick() - xtime seqlock held for write
    -> update_process_times()
    -> run_local_timers()
    -> hrtimer_run_queues()
    -> hrtimer_get_softirq_time() - tries to get a read lock

    Now, Thomas assures me the fix is trivial, only do_timer() needs to be
    done under the xtime_lock, and update_process_times() can savely be removed
    from under it.

    So that is what the next two patches do, the first patch is by Russell and
    covers most of the arm sub-arch, the second one does the other archs and a
    few arm archs that were missed by rmk.

    This patch should probably be folded into one, or at least the arm bits
    from the second moved to the first patch, to avoid more bisect breakage.

    If you're all ok I'll polish the patches (maybe one per arch?) and ask for
    merger.

    (for obvious reasons I'm unable to actually test any of this)

    Peter



    \
     
     \ /
      Last update: 2008-01-28 11:45    [W:0.020 / U:2.192 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site