perf report: Adjust column width to the values sampled

Auto-adjust column width of perf report output to the
longest occuring string length.

Example:

[acme@doppio pahole]$  perf report --sort comm,dso,symbol | head -13

    12.79%   pahole  /usr/lib64/libdw-0.141.so    [.] __libdw_find_attr
     8.90%   pahole  /lib64/libc-2.10.1.so        [.] _int_malloc
     8.68%   pahole  /usr/lib64/libdw-0.141.so    [.] __libdw_form_val_len
     8.15%   pahole  /lib64/libc-2.10.1.so        [.] __GI_strcmp
     6.80%   pahole  /lib64/libc-2.10.1.so        [.] __tsearch
     5.54%   pahole  ./build/libdwarves.so.1.0.0  [.] tag__recode_dwarf_type
[acme@doppio pahole]$

[acme@doppio pahole]$  perf report --sort comm,dso,symbol -d /lib64/libc-2.10.1.so | head -10

    21.92%   pahole  /lib64/libc-2.10.1.so  [.] _int_malloc
    20.08%   pahole  /lib64/libc-2.10.1.so  [.] __GI_strcmp
    16.75%   pahole  /lib64/libc-2.10.1.so  [.] __tsearch
[acme@doppio pahole]$

Also add these extra options to control the new behaviour:

  -w, --field-width

Force each column width to the provided list, for large terminal
readability.

  -t, --field-separator:

Use a special separator character and don't pad with spaces, replacing
all occurances of this separator in symbol names (and other output) with
a '.' character, that thus it's the only non valid separator.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20090711014728.GH3452@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/include/linux/kernel.h b/tools/perf/util/include/linux/kernel.h
index 99c1b3d..a6b8739 100644
--- a/tools/perf/util/include/linux/kernel.h
+++ b/tools/perf/util/include/linux/kernel.h
@@ -18,4 +18,12 @@
 	(type *)((char *)__mptr - offsetof(type, member)); })
 #endif
 
+#ifndef max
+#define max(x, y) ({				\
+	typeof(x) _max1 = (x);			\
+	typeof(y) _max2 = (y);			\
+	(void) (&_max1 == &_max2);		\
+	_max1 > _max2 ? _max1 : _max2; })
+#endif
+
 #endif