perf auxtrace: Add an option to synthesize callchains for regular events

Currently, callchains can be synthesized only for synthesized events. Add
an itrace option to synthesize callchains for regular events.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-9-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/itrace.txt

@@ -10,6 +10,7 @@
 		e	synthesize error events
 		d	create a debug log
 		g	synthesize a call chain (use with i or x)
+		G	synthesize a call chain on existing event records
 		l	synthesize last branch entries (use with i or x)
 		s       skip initial number of events
 

tools/perf/builtin-report.c

@@ -339,6 +339,7 @@ static int report__setup_sample_type(struct report *rep)
 	bool is_pipe = perf_data__is_pipe(session->data);
 
 	if (session->itrace_synth_opts->callchain ||
+	    session->itrace_synth_opts->add_callchain ||
 	    (!is_pipe &&
 	     perf_header__has_feat(&session->header, HEADER_AUXTRACE) &&
 	     !session->itrace_synth_opts->set))
@@ -1332,7 +1333,7 @@ int cmd_report(int argc, const char **argv)
 	if (symbol_conf.cumulate_callchain && !callchain_param.order_set)
 		callchain_param.order = ORDER_CALLER;
 
-	if (itrace_synth_opts.callchain &&
+	if ((itrace_synth_opts.callchain || itrace_synth_opts.add_callchain) &&
 	    (int)itrace_synth_opts.callchain_sz > report.max_stack)
 		report.max_stack = itrace_synth_opts.callchain_sz;
 

tools/perf/builtin-script.c

@@ -3537,7 +3537,7 @@ int cmd_script(int argc, const char **argv)
 		return -1;
 	}
 
-	if (itrace_synth_opts.callchain &&
+	if ((itrace_synth_opts.callchain || itrace_synth_opts.add_callchain) &&
 	    itrace_synth_opts.callchain_sz > scripting_max_stack)
 		scripting_max_stack = itrace_synth_opts.callchain_sz;
 

tools/perf/util/auxtrace.c

@@ -1462,8 +1462,12 @@ int itrace_parse_synth_opts(const struct option *opt, const char *str,
 			synth_opts->branches = true;
 			synth_opts->returns = true;
 			break;
+		case 'G':
 		case 'g':
-			synth_opts->callchain = true;
+			if (p[-1] == 'G')
+				synth_opts->add_callchain = true;
+			else
+				synth_opts->callchain = true;
 			synth_opts->callchain_sz =
 					PERF_ITRACE_DEFAULT_CALLCHAIN_SZ;
 			while (*p == ' ' || *p == ',')

tools/perf/util/auxtrace.h

@@ -74,6 +74,7 @@ enum itrace_period_type {
  * @calls: limit branch samples to calls (can be combined with @returns)
  * @returns: limit branch samples to returns (can be combined with @calls)
  * @callchain: add callchain to 'instructions' events
+ * @add_callchain: add callchain to existing event records
  * @thread_stack: feed branches to the thread_stack
  * @last_branch: add branch context to 'instruction' events
  * @callchain_sz: maximum callchain size
@@ -101,6 +102,7 @@ struct itrace_synth_opts {
 	bool			calls;
 	bool			returns;
 	bool			callchain;
+	bool			add_callchain;
 	bool			thread_stack;
 	bool			last_branch;
 	unsigned int		callchain_sz;

tools/perf/util/s390-cpumsf.c

@@ -1079,7 +1079,7 @@ static bool check_auxtrace_itrace(struct itrace_synth_opts *itops)
 		itops->pwr_events || itops->errors ||
 		itops->dont_decode || itops->calls || itops->returns ||
 		itops->callchain || itops->thread_stack ||
-		itops->last_branch;
+		itops->last_branch || itops->add_callchain;
 	if (!ison)
 		return true;
 	pr_err("Unsupported --itrace options specified\n");