perf script: Add option resolving vmlinux path

Add the option get the path of [kernel.kallsyms].
Specify '--show-kernel-path' option to use this function.
This patch enables other applications to use this output easily.

Without --show-kernel-path  option

ffffffff81467612 irq_return ([kernel.kallsyms])
ffffffff81467612 irq_return ([kernel.kallsyms])
    7f24fc02a6b3 _start (/lib64/ld-2.14.so)
[snip]

With --show-kernel-path option

ffffffff81467612 irq_return (/lib/modules/3.2.0+/build/vmlinux)
ffffffff81467612 irq_return (/lib/modules/3.2.0+/build/vmlinux)
    7f24fc02a6b3 _start (/lib64/ld-2.14.so)
[snip]

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20120130044320.2384.73322.stgit@linux3
Signed-off-by: Akihiro Nagai <akihiro.nagai.hw@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index 228c7bb..e9cbfcd 100644
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -200,6 +200,9 @@
 	It currently includes: cpu and numa topology of the host system.
 	It can only be used with the perf script report mode.
 
+--show-kernel-path::
+	Try to resolve the path of [kernel.kallsyms]
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-script-perl[1],