perf session: Keep pointers to the vmlinux maps

So that tools such as 'perf probe' don't have to lookup
'[kernel.kallsyms]' but instead access them directly after
perf_session__create_kernel_maps or
map_groups__create_kernel_maps.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1262629169-22797-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/builtin-probe.c

@@ -235,9 +235,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
 	session.psession = perf_session__new(NULL, O_WRONLY, false);
 	if (session.psession == NULL)
 		die("Failed to init perf_session.");
-	session.kmap = map_groups__find_by_name(&session.psession->kmaps,
-						MAP__FUNCTION,
-						"[kernel.kallsyms]");
+	session.kmap = session.psession->vmlinux_maps[MAP__FUNCTION];
 	if (!session.kmap)
 		die("Could not find kernel map.\n");
 

tools/perf/util/session.h

@@ -18,6 +18,7 @@ struct perf_session {
 	struct map_groups	kmaps;
 	struct rb_root		threads;
 	struct thread		*last_match;
+	struct map		*vmlinux_maps[MAP__NR_TYPES];
 	struct events_stats	events_stats;
 	unsigned long		event_total[PERF_RECORD_MAX];
 	unsigned long		unknown_events;

tools/perf/util/symbol.c

@@ -1662,7 +1662,7 @@ size_t dsos__fprintf_buildid(FILE *fp)
 		__dsos__fprintf_buildid(&dsos__user, fp));
 }
 
-static struct dso *dsos__create_kernel( const char *vmlinux)
+static struct dso *dsos__create_kernel(const char *vmlinux)
 {
 	struct dso *kernel = dso__new(vmlinux ?: "[kernel.kallsyms]");
 
@@ -1691,29 +1691,26 @@ static struct dso *dsos__create_kernel( const char *vmlinux)
 	return NULL;
 }
 
-static int map_groups__create_kernel_maps(struct map_groups *self, const char *vmlinux)
+static int map_groups__create_kernel_maps(struct map_groups *self,
+					  struct map *vmlinux_maps[MAP__NR_TYPES],
+					  const char *vmlinux)
 {
-	struct map *functions, *variables;
 	struct dso *kernel = dsos__create_kernel(vmlinux);
+	enum map_type type;
 
 	if (kernel == NULL)
 		return -1;
 
-	functions = map__new2(0, kernel, MAP__FUNCTION);
-	if (functions == NULL)
+	for (type = 0; type < MAP__NR_TYPES; ++type) {
+		vmlinux_maps[type] = map__new2(0, kernel, type);
+		if (vmlinux_maps[type] == NULL)
 			return -1;
 
-	variables = map__new2(0, kernel, MAP__VARIABLE);
-	if (variables == NULL) {
-		map__delete(functions);
-		return -1;
+		vmlinux_maps[type]->map_ip =
+			vmlinux_maps[type]->unmap_ip = identity__map_ip;
+		map_groups__insert(self, vmlinux_maps[type]);
 	}
 
-	functions->map_ip = functions->unmap_ip =
-		variables->map_ip = variables->unmap_ip = identity__map_ip;
-	map_groups__insert(self, functions);
-	map_groups__insert(self, variables);
-
 	return 0;
 }
 
@@ -1824,7 +1821,7 @@ int symbol__init(void)
 
 int perf_session__create_kernel_maps(struct perf_session *self)
 {
-	if (map_groups__create_kernel_maps(&self->kmaps,
+	if (map_groups__create_kernel_maps(&self->kmaps, self->vmlinux_maps,
 					   symbol_conf.vmlinux_name) < 0)
 		return -1;