perf symbols: Allow loading kallsyms without considering kcore files

Before the support for using /proc/kcore was introduced, the kallsyms
routines used /proc/modules and the first 'perf test' entry expected
finding maps for each module in the system, which is not the case with
the kcore code. Provide a way to ignore kcore files so that the test can
have its expectations met.

Improving the test to cover kcore files as well needs to be done.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ek5urnu103dlhfk4l6pcw041@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/machine.c

@@ -908,11 +908,11 @@ int machines__create_kernel_maps(struct machines *machines, pid_t pid)
 	return machine__create_kernel_maps(machine);
 }
 
-int machine__load_kallsyms(struct machine *machine, const char *filename,
-			   enum map_type type, symbol_filter_t filter)
+int __machine__load_kallsyms(struct machine *machine, const char *filename,
+			     enum map_type type, bool no_kcore, symbol_filter_t filter)
 {
 	struct map *map = machine__kernel_map(machine);
-	int ret = dso__load_kallsyms(map->dso, filename, map, filter);
+	int ret = __dso__load_kallsyms(map->dso, filename, map, no_kcore, filter);
 
 	if (ret > 0) {
 		dso__set_loaded(map->dso, type);
@@ -927,6 +927,12 @@ int machine__load_kallsyms(struct machine *machine, const char *filename,
 	return ret;
 }
 
+int machine__load_kallsyms(struct machine *machine, const char *filename,
+			   enum map_type type, symbol_filter_t filter)
+{
+	return __machine__load_kallsyms(machine, filename, type, false, filter);
+}
+
 int machine__load_vmlinux_path(struct machine *machine, enum map_type type,
 			       symbol_filter_t filter)
 {

tools/perf/util/machine.h

@@ -215,6 +215,8 @@ struct symbol *machine__find_kernel_function_by_name(struct machine *machine,
 struct map *machine__findnew_module_map(struct machine *machine, u64 start,
 					const char *filename);
 
+int __machine__load_kallsyms(struct machine *machine, const char *filename,
+			     enum map_type type, bool no_kcore, symbol_filter_t filter);
 int machine__load_kallsyms(struct machine *machine, const char *filename,
 			   enum map_type type, symbol_filter_t filter);
 int machine__load_vmlinux_path(struct machine *machine, enum map_type type,

tools/perf/util/symbol.c

@@ -1208,8 +1208,8 @@ static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
 	return 0;
 }
 
-int dso__load_kallsyms(struct dso *dso, const char *filename,
-		       struct map *map, symbol_filter_t filter)
+int __dso__load_kallsyms(struct dso *dso, const char *filename,
+			 struct map *map, bool no_kcore, symbol_filter_t filter)
 {
 	u64 delta = 0;
 
@@ -1230,12 +1230,18 @@ int dso__load_kallsyms(struct dso *dso, const char *filename,
 	else
 		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
 
-	if (!dso__load_kcore(dso, map, filename))
+	if (!no_kcore && !dso__load_kcore(dso, map, filename))
 		return dso__split_kallsyms_for_kcore(dso, map, filter);
 	else
 		return dso__split_kallsyms(dso, map, delta, filter);
 }
 
+int dso__load_kallsyms(struct dso *dso, const char *filename,
+		       struct map *map, symbol_filter_t filter)
+{
+	return __dso__load_kallsyms(dso, filename, map, false, filter);
+}
+
 static int dso__load_perf_map(struct dso *dso, struct map *map,
 			      symbol_filter_t filter)
 {

tools/perf/util/symbol.h

@@ -240,6 +240,8 @@ int dso__load_vmlinux(struct dso *dso, struct map *map,
 		      symbol_filter_t filter);
 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
 			   symbol_filter_t filter);
+int __dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map,
+			 bool no_kcore, symbol_filter_t filter);
 int dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map,
 		       symbol_filter_t filter);