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    SubjectRe: [ofa-general] Re: [GIT PULL] please pull ummunotify
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    > Performance events filtering is being worked on and now with the proper
    > non-DoS limit you've added you can lose events too, dont you? So it's
    > all a question of how much buffering to add - and with perf events too
    > you can buffer arbitrary large amount of events.

    No, the idea for non-DoS for ummunotify is that we would limit the
    number of regions the application can register; so an application might
    hit the limit up front but no runtime loss of events once a region was
    registered successfully.

    > I think this could be done in a simpler, less limited, more generic,
    > more useful form by using some variation of perf events.
    >
    > You should be able to get all that you want by adding two TRACE_EVENT()
    > tracepoints and using the existing perf event syscall to get the events
    > to user-space.

    Yes, I would like to use perf events too. Would it be plausible to
    create a way for userspace to create a "counter" for each address range
    being watched? Then events would not be lost, because those counters
    would become non-zero.

    > Meaning that this:
    > 9 files changed, 1060 insertions(+), 1 deletions(-)

    Note that lots/ of the files touched here are in Documentation or are
    one-line changes to Makefiles etc.

    - R.


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