perf script: Add a setting for maximum stack depth

Add a setting for maximum stack depth in preparation for allowing for
synthesized callchains.

Signed-off-by: Adrian Hunter <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/builtin-script.c

···
 static const char		*cpu_list;
 static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
 
+static unsigned int scripting_max_stack = PERF_MAX_STACK_DEPTH;
+
 enum perf_output_field {
 	PERF_OUTPUT_COMM            = 1U << 0,
 	PERF_OUTPUT_TID             = 1U << 1,
···
 			}
 		}
 		perf_evsel__print_ip(evsel, sample, al, print_opts,
-				     PERF_MAX_STACK_DEPTH);
+				     scripting_max_stack);
 	}
 
 	/* print branch_to information */
···
 
 		perf_evsel__print_ip(evsel, sample, al,
 				     output[attr->type].print_ip_opts,
-				     PERF_MAX_STACK_DEPTH);
+				     scripting_max_stack);
 	}
 
 	if (PRINT_FIELD(IREGS))

tools/perf/util/session.c

···
 
 		if (thread__resolve_callchain(al->thread, evsel,
 					      sample, NULL, NULL,
-					      PERF_MAX_STACK_DEPTH) != 0) {
+					      stack_depth) != 0) {
 			if (verbose)
 				error("Failed to resolve callchain. Skipping\n");
 			return;