perf symbols: Rename kthreads to kmaps, using another abstraction for it

Using a struct thread instance just to hold the kernel space maps
(vmlinux + modules) is overkill and confuses people trying to
understand the perf symbols abstractions.

The kernel maps are really present in all threads, i.e. the kernel
is a library, not a separate thread.

So introduce the 'map_groups' abstraction and use it for the kernel
maps, now in the kmaps global variable.

It, in turn, will move, together with the threads list to the
perf_file abstraction, so that we can support multiple perf_file
instances, needed by perf diff.

Brainstormed-with: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Eduardo Habkost <ehabkost@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: <1260550239-5372-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 35 insertions, 27 deletions

diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 603f561..a128512 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -9,11 +9,9 @@
 static struct rb_root threads;
 static struct thread *last_match;
 
-void thread__init(struct thread *self, pid_t pid)
+void map_groups__init(struct map_groups *self)
 {
 	int i;
-	self->pid = pid;
-	self->comm = NULL;
 	for (i = 0; i < MAP__NR_TYPES; ++i) {
 		self->maps[i] = RB_ROOT;
 		INIT_LIST_HEAD(&self->removed_maps[i]);
@@ -25,7 +23,8 @@ static struct thread *thread__new(pid_t pid)
 	struct thread *self = zalloc(sizeof(*self));
 
 	if (self != NULL) {
-		thread__init(self, pid);
+		map_groups__init(&self->mg);
+		self->pid = pid;
 		self->comm = malloc(32);
 		if (self->comm)
 			snprintf(self->comm, 32, ":%d", self->pid);
@@ -57,8 +56,8 @@ static const char *map_type__name[MAP__NR_TYPES] = {
 	[MAP__FUNCTION] = "Functions",
 };
 
-static size_t __thread__fprintf_maps(struct thread *self,
-				     enum map_type type, FILE *fp)
+static size_t __map_groups__fprintf_maps(struct map_groups *self,
+					 enum map_type type, FILE *fp)
 {
 	size_t printed = fprintf(fp, "%s:\n", map_type__name[type]);
 	struct rb_node *nd;
@@ -76,16 +75,16 @@ static size_t __thread__fprintf_maps(struct thread *self,
 	return printed;
 }
 
-size_t thread__fprintf_maps(struct thread *self, FILE *fp)
+size_t map_groups__fprintf_maps(struct map_groups *self, FILE *fp)
 {
 	size_t printed = 0, i;
 	for (i = 0; i < MAP__NR_TYPES; ++i)
-		printed += __thread__fprintf_maps(self, i, fp);
+		printed += __map_groups__fprintf_maps(self, i, fp);
 	return printed;
 }
 
-static size_t __thread__fprintf_removed_maps(struct thread *self,
-					     enum map_type type, FILE *fp)
+static size_t __map_groups__fprintf_removed_maps(struct map_groups *self,
+						 enum map_type type, FILE *fp)
 {
 	struct map *pos;
 	size_t printed = 0;
@@ -101,20 +100,25 @@ static size_t __thread__fprintf_removed_maps(struct thread *self,
 	return printed;
 }
 
-static size_t thread__fprintf_removed_maps(struct thread *self, FILE *fp)
+static size_t map_groups__fprintf_removed_maps(struct map_groups *self, FILE *fp)
 {
 	size_t printed = 0, i;
 	for (i = 0; i < MAP__NR_TYPES; ++i)
-		printed += __thread__fprintf_removed_maps(self, i, fp);
+		printed += __map_groups__fprintf_removed_maps(self, i, fp);
 	return printed;
 }
 
-static size_t thread__fprintf(struct thread *self, FILE *fp)
+static size_t map_groups__fprintf(struct map_groups *self, FILE *fp)
 {
-	size_t printed = fprintf(fp, "Thread %d %s\n", self->pid, self->comm);
-	printed += thread__fprintf_removed_maps(self, fp);
+	size_t printed = map_groups__fprintf_maps(self, fp);
 	printed += fprintf(fp, "Removed maps:\n");
-	return printed + thread__fprintf_removed_maps(self, fp);
+	return printed + map_groups__fprintf_removed_maps(self, fp);
+}
+
+static size_t thread__fprintf(struct thread *self, FILE *fp)
+{
+	return fprintf(fp, "Thread %d %s\n", self->pid, self->comm) +
+	       map_groups__fprintf(&self->mg, fp);
 }
 
 struct thread *threads__findnew(pid_t pid)
@@ -168,7 +172,8 @@ struct thread *register_idle_thread(void)
 	return thread;
 }
 
-static void thread__remove_overlappings(struct thread *self, struct map *map)
+static void map_groups__remove_overlappings(struct map_groups *self,
+					    struct map *map)
 {
 	struct rb_root *root = &self->maps[map->type];
 	struct rb_node *next = rb_first(root);
@@ -238,12 +243,15 @@ struct map *maps__find(struct rb_root *maps, u64 ip)
 
 void thread__insert_map(struct thread *self, struct map *map)
 {
-	thread__remove_overlappings(self, map);
-	maps__insert(&self->maps[map->type], map);
+	map_groups__remove_overlappings(&self->mg, map);
+	map_groups__insert(&self->mg, map);
 }
 
-static int thread__clone_maps(struct thread *self, struct thread *parent,
-			      enum map_type type)
+/*
+ * XXX This should not really _copy_ te maps, but refcount them.
+ */
+static int map_groups__clone(struct map_groups *self,
+			     struct map_groups *parent, enum map_type type)
 {
 	struct rb_node *nd;
 	for (nd = rb_first(&parent->maps[type]); nd; nd = rb_next(nd)) {
@@ -251,7 +259,7 @@ static int thread__clone_maps(struct thread *self, struct thread *parent,
 		struct map *new = map__clone(map);
 		if (new == NULL)
 			return -ENOMEM;
-		thread__insert_map(self, new);
+		map_groups__insert(self, new);
 	}
 	return 0;
 }
@@ -267,7 +275,7 @@ int thread__fork(struct thread *self, struct thread *parent)
 		return -ENOMEM;
 
 	for (i = 0; i < MAP__NR_TYPES; ++i)
-		if (thread__clone_maps(self, parent, i) < 0)
+		if (map_groups__clone(&self->mg, &parent->mg, i) < 0)
 			return -ENOMEM;
 	return 0;
 }
@@ -286,11 +294,11 @@ size_t threads__fprintf(FILE *fp)
 	return ret;
 }
 
-struct symbol *thread__find_symbol(struct thread *self,
-				   enum map_type type, u64 addr,
-				   symbol_filter_t filter)
+struct symbol *map_groups__find_symbol(struct map_groups *self,
+				       enum map_type type, u64 addr,
+				       symbol_filter_t filter)
 {
-	struct map *map = thread__find_map(self, type, addr);
+	struct map *map = map_groups__find(self, type, addr);
 
 	if (map != NULL)
 		return map__find_symbol(map, map->map_ip(map, addr), filter);