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    SubjectRe: tun.c patch to fix "smp_processor_id() in preemptible code"
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    On Tue, 2004-10-19 at 17:54, Herbert Xu wrote:
    > On Tue, Oct 19, 2004 at 05:51:17PM -0400, Lee Revell wrote:
    > >
    > > Ok, here is the correct patch. If this is really just a matter of
    > > performance, and not required for correctness, disabling preemption is
    > > broken, right?
    >
    > No if you're doing this then you should get rid of netif_rx_ni()
    > altogether. But before you do that please ask all the people who
    > call it.

    There are not a lot of them:

    drivers/s390/net/ctcmain.c
    drivers/s390/net/netiucv.c
    drivers/net/irda/vlsi_ir.c
    drivers/net/tun.c

    >From netiuvc.c:

    /*
    * Since receiving is always initiated from a tasklet (in iucv.c),
    * we must use netif_rx_ni() instead of netif_rx()
    */

    This implies that the author thought it was a matter of correctness to
    use netif_rx_ni vs. netif_rx. But it looks like the only difference is
    that the former sacrifices preempt-safety for performance.

    I could not find maintainers for the two s390 drivers, or a specific
    maintainer for vlsi_ir.

    Lee

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