perf evsel: Skip ignored symbols while printing callchain
perf evsel: Skip ignored symbols while printing callchain

Allows a command to have a symbol_filter controlled by the user to skip
certain functions in a backtrace. One example is to allow the user to
reduce repeating patterns like:

    do_select  core_sys_select  sys_select

to just sys_select when dumping callchains, consuming less real estate
on the screen while still conveying the essential message - the process
is in a select call.

This option is leveraged by the upcoming timehist command.

Signed-off-by: David Ahern <b80c1600f604d3b0d768f26f90a76757e76005dd@gmail.com>
Cc: Adrian Hunter <41bb5944f244750b7cf0394140496972a3f1bee3@intel.com>
Cc: Frederic Weisbecker <e8a1bf9163cb25e93cfd6540f223b3872ea7ee55@gmail.com>
Cc: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@kernel.org>
Cc: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Cc: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Cc: Stephane Eranian <f199ae9781930a5b94b284ca2f471140752002a7@google.com>
Link: http://lkml.kernel.org/r/1384806771-2945-2-git-send-email-b80c1600f604d3b0d768f26f90a76757e76005dd@gmail.com
[ Checked if al.sym is NULL before touching al.sym->ignored, as noted by Adrian Hunter ]
Signed-off-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs