perf scripting python: Allow for max_stack greater than PERF_MAX_STACK_DEPTH

Use the scripting_max_stack value to allow for values greater than
PERF_MAX_STACK_DEPTH.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1443186956-18718-20-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-script.c

@@ -33,7 +33,7 @@ static bool			nanosecs;
 static const char		*cpu_list;
 static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
 
-static unsigned int scripting_max_stack = PERF_MAX_STACK_DEPTH;
+unsigned int scripting_max_stack = PERF_MAX_STACK_DEPTH;
 
 enum perf_output_field {
 	PERF_OUTPUT_COMM            = 1U << 0,

tools/perf/util/scripting-engines/trace-event-python.c

@@ -319,7 +319,7 @@ static PyObject *python_process_callchain(struct perf_sample *sample,
 
 	if (thread__resolve_callchain(al->thread, evsel,
 				      sample, NULL, NULL,
-				      PERF_MAX_STACK_DEPTH) != 0) {
+				      scripting_max_stack) != 0) {
 		pr_err("Failed to resolve callchain. Skipping\n");
 		goto exit;
 	}

tools/perf/util/trace-event.h

@@ -78,6 +78,8 @@ struct scripting_ops {
 	int (*generate_script) (struct pevent *pevent, const char *outfile);
 };
 
+extern unsigned int scripting_max_stack;
+
 int script_spec_register(const char *spec, struct scripting_ops *ops);
 
 void setup_perl_scripting(void);