perf report: Introduce helpers for processing callchains

Continuing to try to remove the code duplication introduced with mem and
branch hist entry code, this time providing prologue and epilogues to
deal with callchains when processing samples.
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-js3pour59yk2aibqzb1tpumh@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-report.c

@@ -75,6 +75,24 @@ static int perf_report_config(const char *var, const char *value, void *cb)
 	return perf_default_config(var, value, cb);
 }
 
+static int report__resolve_callchain(struct perf_report *rep, struct symbol **parent,
+				     struct perf_evsel *evsel, struct addr_location *al,
+				     struct perf_sample *sample, struct machine *machine)
+{
+	if ((sort__has_parent || symbol_conf.use_callchain) && sample->callchain) {
+		return machine__resolve_callchain(machine, evsel, al->thread, sample,
+						  parent, al, rep->max_stack);
+	}
+	return 0;
+}
+
+static int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *sample)
+{
+	if (!symbol_conf.use_callchain)
+		return 0;
+	return callchain_append(he->callchain, &callchain_cursor, sample->period);
+}
+
 static int perf_report__add_mem_hist_entry(struct perf_tool *tool,
 					   struct addr_location *al,
 					   struct perf_sample *sample,
@@ -85,19 +103,13 @@ static int perf_report__add_mem_hist_entry(struct perf_tool *tool,
 	struct perf_report *rep = container_of(tool, struct perf_report, tool);
 	struct symbol *parent = NULL;
 	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
-	int err = 0;
 	struct hist_entry *he;
 	struct mem_info *mi, *mx;
 	uint64_t cost;
+	int err = report__resolve_callchain(rep, &parent, evsel, al, sample, machine);
 
-	if ((sort__has_parent || symbol_conf.use_callchain) &&
-	    sample->callchain) {
-		err = machine__resolve_callchain(machine, evsel, al->thread,
-						 sample, &parent, al,
-						 rep->max_stack);
-		if (err)
-			return err;
-	}
+	if (err)
+		return err;
 
 	mi = machine__resolve_mem(machine, al->thread, sample, cpumode);
 	if (!mi)
@@ -133,13 +145,7 @@ static int perf_report__add_mem_hist_entry(struct perf_tool *tool,
 
 	evsel->hists.stats.total_period += cost;
 	hists__inc_nr_events(&evsel->hists, PERF_RECORD_SAMPLE);
-	err = 0;
-
-	if (symbol_conf.use_callchain) {
-		err = callchain_append(he->callchain,
-				       &callchain_cursor,
-				       sample->period);
-	}
+	err = hist_entry__append_callchain(he, sample);
 out:
 	return err;
 }
@@ -152,19 +158,13 @@ static int perf_report__add_branch_hist_entry(struct perf_tool *tool,
 {
 	struct perf_report *rep = container_of(tool, struct perf_report, tool);
 	struct symbol *parent = NULL;
-	int err = 0;
 	unsigned i;
 	struct hist_entry *he;
 	struct branch_info *bi, *bx;
+	int err = report__resolve_callchain(rep, &parent, evsel, al, sample, machine);
 
-	if ((sort__has_parent || symbol_conf.use_callchain)
-	    && sample->callchain) {
-		err = machine__resolve_callchain(machine, evsel, al->thread,
-						 sample, &parent, al,
-						 rep->max_stack);
-		if (err)
-			return err;
-	}
+	if (err)
+		return err;
 
 	bi = machine__resolve_bstack(machine, al->thread,
 				     sample->branch_stack);
@@ -216,16 +216,11 @@ static int perf_evsel__add_hist_entry(struct perf_tool *tool,
 {
 	struct perf_report *rep = container_of(tool, struct perf_report, tool);
 	struct symbol *parent = NULL;
-	int err = 0;
 	struct hist_entry *he;
+	int err = report__resolve_callchain(rep, &parent, evsel, al, sample, machine);
 
-	if ((sort__has_parent || symbol_conf.use_callchain) && sample->callchain) {
-		err = machine__resolve_callchain(machine, evsel, al->thread,
-						 sample, &parent, al,
-						 rep->max_stack);
-		if (err)
-			return err;
-	}
+	if (err)
+		return err;
 
 	he = __hists__add_entry(&evsel->hists, al, parent, NULL, NULL,
 				sample->period, sample->weight,
@@ -233,17 +228,14 @@ static int perf_evsel__add_hist_entry(struct perf_tool *tool,
 	if (he == NULL)
 		return -ENOMEM;
 
-	if (symbol_conf.use_callchain) {
-		err = callchain_append(he->callchain,
-				       &callchain_cursor,
-				       sample->period);
-		if (err)
-			return err;
-	}
+	err = hist_entry__append_callchain(he, sample);
+	if (err)
+		goto out;
 
 	err = hist_entry__inc_addr_samples(he, evsel->idx, al->addr);
 	evsel->hists.stats.total_period += sample->period;
 	hists__inc_nr_events(&evsel->hists, PERF_RECORD_SAMPLE);
+out:
 	return err;
 }