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    SubjectRE: [PATCH V3 3/3] perf tools: Construct LBR call chain
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    > On Tue, Nov 18, 2014 at 03:13:50PM +0900, Namhyung Kim wrote:
    >
    > SNIP
    >
    > > >> > + * in "from" register, while the callee is
    > stored
    > > >> > + * in "to" register.
    > > >> > + * For example, there is a call stack
    > > >> > + * "A"->"B"->"C"->"D".
    > > >> > + * The LBR registers will recorde like
    > > >> > + * "C"->"D", "B"->"C", "A"->"B".
    > > >> > + * So only the first "to" register and all
    > "from"
    > > >> > + * registers are needed to construct the
    > whole
    > > >> stack.
    > > >> > + */
    > > >>
    > > >> Andi is using some sanity checks:
    > > >> http://marc.info/?l=linux-kernel&m=141584447819894&w=2
    > > >> I guess this could be applied in here, once his patch gets in.
    > > >>
    > > >
    > > > Are you suggesting me to remove the comments, or rebase the whole
    > > > patch to Andi's patch once it's merged?
    > > >
    > > > The branch history in Andi's patch is different as the call stack,
    > > > although they are both from LBR.
    > > > Andi's branch history recording branch records for taken branches,
    > > > interrupts, and exceptions.
    > > > While the LBR call stack records for the call stack.
    > >
    > > Right. And branch history can overlap with normal callchains so
    > > additional check in there is to remove duplication. While LBR call
    > > stack is separated to user only so there should be no overlap.
    >
    > hum, it seemed to me like the remove_loops function could be used for
    > this one as well.. but anyway I meant that this can be introduced later after
    > Andi's change gets in

    I see. I will apply Andi's remove_loops.

    Thanks,
    Kan

    >
    > thanks,
    > jirka


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