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    SubjectRe: [PATCH] Linux Kernel Markers 0.13 for 2.6.17
    Mathieu Desnoyers wrote:
    > Just as a precision :
    >
    > The following sequence (please refer to the code below for local symbols
    > 1 and 2) :
    >
    > 1:
    > preempt_disable()
    > call (*__mark_call_##name)(format, ## args);
    > preempt_enable_no_resched()
    > 2:
    >
    > is insured because :
    >
    > 1 is part of an inline assembly with rw dependency on __marker_sequencer
    > the call is surrounded by memory barriers.
    > 2 is part of an inline assembly with rw dependency on __marker_sequencer
    >

    What do you mean the call is surrounded by memory barriers? Do you mean
    a call has an implicit barrier, or something else?

    Either way, this doesn't prevent some otherwise unrelated
    non-memory-using code from being scheduled in there, which would not be
    executed. The gcc manual really strongly discourages jumping between
    inline asms, because they have basically unpredictable results.

    J
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