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    SubjectRe: [PATCH v7 11/18] perf tools: add mem access sampling core support
    Em Wed, Mar 27, 2013 at 03:48:15PM +0100, Stephane Eranian escreveu:
    > On Wed, Mar 27, 2013 at 3:34 PM, Jiri Olsa <jolsa@redhat.com> wrote:
    > > On Wed, Mar 27, 2013 at 03:20:14PM +0100, Peter Zijlstra wrote:
    > > > On Wed, 2013-03-27 at 15:14 +0100, Jiri Olsa wrote:
    > > > > we have correct cpumode for sample->ip, but I think it's the
    > > > > PEBS->dla (sample->addr) where we need to guess.. right?

    > > > kernel mode very much fakes the cpumode/segment stuff for PEBS. PEBS
    > > > assumes you're running in a linear/flat mode.

    > > say we hit the sample when kernel accesses the user data, we will endup
    > > with IP in kernel space and DATA ptr in user space.. in theory ;-)

    > Yes, this is possible. So I think we could probably leaverage ip__resolve_ams()
    > and pass the extra parameter for MAP_VARIABLE vs. MAP_FUNCTION.

    BTW, I fixed up the patches (kernel and user parts) and have them in
    perf/mem at:

    git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

    Hope to push it to Ingo today/tomorrow, after some more testing, thanks
    Jiri for reviewing it.

    Stephane, if you could give it a try again to see that the fixups I did
    (documented in the commit logs, just before my Signed-off-by) are ok,
    that would be good.

    - Arnaldo

    >
    > >
    > > and that would need the cpumode guessing for DATA ptr, because
    > > cpumode value is deduced from cs register
    > >
    > > jirka


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