lkml.org 
[lkml]   [2009]   [Jun]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [patch] x64: Avoid irq_chip mask/unmask in fixup_irqs for interrupt-remapping
    From
    Date
    On Thu, 2009-06-04 at 16:13 -0700, Eric W. Biederman wrote:
    > Suresh Siddha <suresh.b.siddha@intel.com> writes:
    >
    > > From: Suresh Siddha <suresh.b.siddha@intel.com>
    > > Subject: x64: Avoid irq_chip mask/unmask in fixup_irqs for interrupt-remapping
    > >
    > > In the presence of interrupt-remapping, irqs will be migrated in the
    > > process context and we don't do (and there is no need to) irq_chip mask/unmask
    > > while migrating the interrupt.
    > >
    > > Similarly fix the fixup_irqs() that get called during cpu offline and avoid
    > > calling irq_chip mask/unmask for irqs that are ok to be migrated in the
    > > process context.
    > >
    > > While we didn't observe any race condition with the existing code,
    > > this change takes complete advantage of interrupt-remapping in
    > > the newer generation platforms and avoids any potential HW lockup's
    > > (that often worry Eric :)
    >
    > You now apparently fail to migrate the irq threads in tandem with
    > the rest of the irqs.

    Eric, Are you referring to Gary's issues? As far as I understand, they
    don't happen in the presence of interrupt-remapping.

    Can you ack this patch, as this avoid touching IO-APIC and MSI entries
    and does fixup_irqs() in a much more reliable fashion.

    I haven't followed Gary's couple of patches related to non
    interrupt-remapping case. I will go through them and see how I can help
    there.

    thanks,
    suresh



    \
     
     \ /
      Last update: 2009-06-05 03:23    [W:0.027 / U:98.836 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site