This patch adds a simple GTK2-based browser to 'perf report' that's
based on the TTY-based browser in builtin-report.c.

To launch "perf report" using the new GTK interface just type:

  $ perf report --gtk

The interface is somewhat limited in features at the moment:

  - No callgraph support

  - No KVM guest profiling support

  - No color coding for percentages

  - No sorting from the UI

  - ..and many, many more!

That said, I think this patch a reasonable start to build future features on.
Signed-off-by: NPekka Enberg <penberg@kernel.org>
Cc: Colin Walters <walters@verbum.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202231952410.6689@tux.localdomain
[ committer note: Added #pragma to make gtk no strict prototype problem go
  away as suggested by Colin Walters modulo avoiding push/pop ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Signed-off-by: NMichael Witten <mfwitten@gmail.com>
Link: http://lkml.kernel.org/n/tip-a6zhefjayuounko1tk5sjji2@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The `try-cc' user-defined function was in tools/perf/feature-tests.mak;
this commit moves it to tools/perf/config/utilities.mak.
Signed-off-by: NMichael Witten <mfwitten@gmail.com>
Link: http://lkml.kernel.org/n/tip-bqhwcuxsrve0iodn6q4ejaoi@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently, Python 3 is not supported by perf's code; this
can cause the build to fail for systems that have Python 3
installed as the default python:

  python{,-config}

The Correct Solution is to write compatibility code so that
Python 3 works out-of-the-box.

However, users often have an ancillary Python 2 installed:

  python2{,-config}

Therefore, a quick fix is to allow the user to specify those
ancillary paths as the python binaries that Makefile should
use, thereby avoiding Python 3 altogether; as an added benefit,
the Python binaries may be installed in non-standard locations
without the need for updating any PATH variable.

This commit adds the ability to set PYTHON and/or PYTHON_CONFIG
either as environment variables or as make variables on the
command line; the paths may be relative, and usually only PYTHON
is necessary in order for PYTHON_CONFIG to be defined implicitly.
Some rudimentary error checking is performed when the user
explicitly specifies a value for any of these variables.

In addition, this commit introduces significantly robust makefile
infrastructure for working with paths and communicating with the
shell; it's currently only used for handling Python, but I hope
it will prove useful in refactoring the makefiles.

Thanks to:

  Raghavendra D Prabhu <rprabhu@wnohang.net>

for motivating this patch.
Acked-by: NRaghavendra D Prabhu <rprabhu@wnohang.net>
Link: http://lkml.kernel.org/r/e987828e-87ec-4973-95e7-47f10f5d9bab-mfwitten@gmail.comSigned-off-by: NMichael Witten <mfwitten@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>