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    SubjectRe: [PATCH 2/2] perf: Add a new sort order: SORT_INCLUSIVE
    On Thu, Mar 08, 2012 at 04:39:36PM +0100, Frederic Weisbecker wrote:
    >
    > I don't yet understand the point of this.
    >
    > Imagine those three hists:
    >
    > a -> b -> c
    > a -> b -> d
    > a-> e -> f
    >
    > The fractal inverted mode (-G) will report this:
    >
    > a--
    > |
    > ----- b
    > | |
    > | -----c
    > | |
    > | -----d
    > |
    > ----- e
    > |
    > -----f
    >

    Please see the test program attached. It has only two paths from main()
    to c(). But for this discussion, imagine a callgraph with 10 different
    paths.

    With -G, c() appears 10 times in the callgraph and the user is required
    to manually sum up the samples to realize that the callgraph under c()
    is very expensive.

    With -s inclusive, c() will show up at the very top after main().

    -Arun

    #include <stdio.h>

    int sum = 0;

    #define LOOP(n) \
    { \
    int j; \
    for (j = 0; j < 10000; j++) { \
    sum += j; \
    } \
    }

    int f()
    {
    LOOP(100);
    }

    int d()
    {
    LOOP(100);
    f();
    }

    int e()
    {
    LOOP(100);
    f();
    }

    int c()
    {
    LOOP(100);
    d();
    LOOP(100);
    e();
    }

    int b()
    {
    LOOP(70);
    c();
    }

    int a()
    {
    LOOP(30);
    c();
    }

    int main()
    {
    int i;
    for (i = 0; i < 10000; i++) {
    a();
    b();
    }
    }



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