perf tools: Fix display of first level of callchains
authorFrederic Weisbecker <fweisbec@gmail.com>
Fri, 23 Mar 2012 18:06:50 +0000 (19:06 +0100)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Mon, 26 Mar 2012 18:14:40 +0000 (15:14 -0300)
commit6d4818c5245fe00bee2c3bfb45edde178f302703
treeefceca0975d71d413f0dc9c990afb1893b707934
parentb01c3a0010aabadf745f3e7fdb9cab682e0a28a2
perf tools: Fix display of first level of callchains

The callchain stdio mode display was written using a sorted by symbol
report. In this mode we have only one callchain root per hist so we
forgot to handle cases where we have multiple callchain root, as in per
dso sorting for example.

Fix this by handling these roots like any other branch, with the hist as
the parent.

Before:

     1.97%  libpthread-2.12.1.so
            |
            --- __libc_write
                create_worker
                bench_sched_messaging
                cmd_bench
                run_builtin
                main
                __libc_start_main

            |
            --- __libc_read
                create_worker
                bench_sched_messaging
                cmd_bench
                run_builtin
                main
                __libc_start_main

After:

     1.97%  libpthread-2.12.1.so
            |
            |--36.97%-- __libc_write
            |          create_worker
            |          bench_sched_messaging
            |          cmd_bench
            |          run_builtin
            |          main
            |          __libc_start_main
            |
            |--31.47%-- __libc_read
            |          create_worker
            |          bench_sched_messaging
            |          cmd_bench
            |          run_builtin
            |          main
            |          __libc_start_main
           ...

Single roots keep their entry without percentage because they have
the same overhead than the hist they refer to. ie: 100% in fractal
mode and the percentage of the hist in graph mode:

     0.00%  [k] reschedule_interrupt
            |
            --- default_idle
                amd_e400_idle
                cpu_idle
                start_secondary

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1332526010-15400-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/util/hist.c