perf trace: Make --pf honour --min-stack too

To check deeply nested page fault callchains.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wuji34xx003kr88nmqt6jkgf@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-trace.c

@@ -2190,8 +2190,19 @@ static int trace__pgfault(struct trace *trace,
 	char map_type = 'd';
 	struct thread_trace *ttrace;
 	int err = -1;
+	int callchain_ret = 0;
 
 	thread = machine__findnew_thread(trace->host, sample->pid, sample->tid);
+
+	if (sample->callchain) {
+		callchain_ret = trace__resolve_callchain(trace, evsel, sample, &callchain_cursor);
+		if (callchain_ret == 0) {
+			if (callchain_cursor.nr < trace->min_stack)
+				goto out_put;
+			callchain_ret = 1;
+		}
+	}
+
 	ttrace = thread__trace(thread, trace->output);
 	if (ttrace == NULL)
 		goto out_put;
@@ -2234,10 +2245,10 @@ static int trace__pgfault(struct trace *trace,
 
 	fprintf(trace->output, " (%c%c)\n", map_type, al.level);
 
-	if (sample->callchain) {
-		if (trace__resolve_callchain(trace, evsel, sample, &callchain_cursor) == 0)
+	if (callchain_ret > 0)
 		trace__fprintf_callchain(trace, sample);
-	}
+	else if (callchain_ret < 0)
+		pr_err("Problem processing %s callchain, skipping...\n", perf_evsel__name(evsel));
 out:
 	err = 0;
 out_put: