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    SubjectRe: [PATCH 0/2] Kill unused parameter to smp_call_function and friends

    > > It bothers me how the smp call functions accept a 'nonatomic' or 'retry'
    > > parameter (depending on who you ask), but don't do anything with it.
    > > So kill that silly thing.
    > >
    > > Two patches here, one for smp_call_function*() and one for on_each_cpu().
    > > This patchset applies on top of the generic-ipi patchset just sent out.
    > Which leads to notice that we seem to have acquired a bug somewhere on
    > the way. smp_call_function on x86 is it seems to me implemented as
    > "smp_call_function and occasionally run it multiple times"
    > One of the joys of the older x86 APIC setups is the APIC messaging bus.
    > This can get checksum errors in which case the message is retransmitted:
    > In the specific case a message is retransmitted and there are at least
    > three parties on the bus (2 CPU APICs and an IOAPIC is enough) you can
    > get a situation where one receiver gets the message the second receiver
    > errors it and the retransmit causes the IPI to be repeated which causes
    > the IPI to be redelivered.

    Does that mean smp_call_function on i386 should have a bitmap of cpus
    the message was already delivered to, and drop the duplicates?

    (cesky, pictures)

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