From 825bc2fb040e82c3385b5c87bb49b82359913f0b Mon Sep 17 00:00:00 2001
From: Pavel Fedin
Date: Wed, 21 Feb 2018 13:33:58 -0500
Subject: [PATCH] qom: Replace object property list with GHashTable
ARM GICv3 systems with large number of CPUs create lots of IRQ pins. Since
every pin is represented as a property, number of these properties becomes
very large. Every property add first makes sure there's no duplicates.
Traversing the list becomes very slow, therefore QEMU initialization takes
significant time (several seconds for e. g. 16 CPUs).
This patch replaces list with GHashTable, making lookup very fast. The only
drawback is that object_child_foreach() and object_child_foreach_recursive()
cannot add or remove properties during traversal, since GHashTableIter does
not have modify-safe version. However, the code seems not to modify objects
via these functions.
Backports commit b604a854e843505007c59d68112c654556102a20 from qemu
---
qemu/include/qom/object.h | 10 +++-
qemu/qom/object.c | 117 ++++++++++++++++++++++++--------------
2 files changed, 82 insertions(+), 45 deletions(-)
diff --git a/qemu/include/qom/object.h b/qemu/include/qom/object.h
index bd464bdd..9f400f50 100644
--- a/qemu/include/qom/object.h
+++ b/qemu/include/qom/object.h
@@ -344,8 +344,6 @@ typedef struct ObjectProperty
ObjectPropertyResolve *resolve;
ObjectPropertyRelease *release;
void *opaque;
-
- QTAILQ_ENTRY(ObjectProperty) node;
} ObjectProperty;
/**
@@ -405,7 +403,7 @@ struct Object
/*< private >*/
ObjectClass *class;
ObjectFree *free;
- QTAILQ_HEAD(, ObjectProperty) properties;
+ GHashTable *properties;
uint32_t ref;
Object *parent;
};
@@ -1289,6 +1287,9 @@ void object_property_set_description(Object *obj, const char *name,
* Call @fn passing each child of @obj and @opaque to it, until @fn returns
* non-zero.
*
+ * It is forbidden to add or remove children from @obj from the @fn
+ * callback.
+ *
* Returns: The last value returned by @fn, or 0 if there is no child.
*/
int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
@@ -1304,6 +1305,9 @@ int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
* non-zero. Calls recursively, all child nodes of @obj will also be passed
* all the way down to the leaf nodes of the tree. Depth first ordering.
*
+ * It is forbidden to add or remove children from @obj (or its
+ * child nodes) from the @fn callback.
+ *
* Returns: The last value returned by @fn, or 0 if there is no child.
*/
int object_child_foreach_recursive(Object *obj,
diff --git a/qemu/qom/object.c b/qemu/qom/object.c
index a0c1d7bb..6abb8484 100644
--- a/qemu/qom/object.c
+++ b/qemu/qom/object.c
@@ -67,7 +67,7 @@ struct TypeImpl
};
struct ObjectPropertyIterator {
- ObjectProperty *next;
+ GHashTableIter iter;
};
static GHashTable *type_table_get(struct uc_struct *uc)
@@ -325,6 +325,16 @@ static void object_post_init_with_type(struct uc_struct *uc, Object *obj, TypeIm
}
}
+static void object_property_free(gpointer data)
+{
+ ObjectProperty *prop = data;
+
+ g_free(prop->name);
+ g_free(prop->type);
+ g_free(prop->description);
+ g_free(prop);
+}
+
static void object_initialize_with_type(struct uc_struct *uc, void *data, size_t size, TypeImpl *type)
{
Object *obj = data;
@@ -339,7 +349,8 @@ static void object_initialize_with_type(struct uc_struct *uc, void *data, size_t
memset(obj, 0, type->instance_size);
obj->class = type->class;
object_ref(obj);
- QTAILQ_INIT(&obj->properties);
+ obj->properties = g_hash_table_new_full(g_str_hash, g_str_equal,
+ NULL, object_property_free);
object_init_with_type(uc, obj, type);
object_post_init_with_type(uc, obj, type);
}
@@ -358,29 +369,51 @@ static inline bool object_property_is_child(ObjectProperty *prop)
static void object_property_del_all(struct uc_struct *uc, Object *obj)
{
- while (!QTAILQ_EMPTY(&obj->properties)) {
- ObjectProperty *prop = QTAILQ_FIRST(&obj->properties);
+ ObjectProperty *prop;
+ GHashTableIter iter;
+ gpointer key, value;
+ bool released;
- QTAILQ_REMOVE(&obj->properties, prop, node);
-
- if (prop->release) {
- prop->release(uc, obj, prop->name, prop->opaque);
+ do {
+ released = false;
+ g_hash_table_iter_init(&iter, obj->properties);
+ while (g_hash_table_iter_next(&iter, &key, &value)) {
+ prop = value;
+ if (prop->release) {
+ prop->release(uc, obj, prop->name, prop->opaque);
+ prop->release = NULL;
+ released = true;
+ break;
+ }
+ g_hash_table_iter_remove(&iter);
}
+ } while (released);
- g_free(prop->name);
- g_free(prop->type);
- g_free(prop->description);
- g_free(prop);
- }
+ g_hash_table_unref(obj->properties);
}
void object_property_del_child(struct uc_struct *uc, Object *obj, Object *child, Error **errp)
{
ObjectProperty *prop;
+ GHashTableIter iter;
+ gpointer key, value;
- QTAILQ_FOREACH(prop, &obj->properties, node) {
+ g_hash_table_iter_init(&iter, obj->properties);
+ while (g_hash_table_iter_next(&iter, &key, &value)) {
+ prop = value;
if (object_property_is_child(prop) && prop->opaque == child) {
- object_property_del(uc, obj, prop->name, errp);
+ if (prop->release) {
+ prop->release(uc, obj, prop->name, prop->opaque);
+ prop->release = NULL;
+ }
+ break;
+ }
+ }
+ g_hash_table_iter_init(&iter, obj->properties);
+ while (g_hash_table_iter_next(&iter, &key, &value)) {
+ prop = value;
+ if (object_property_is_child(prop) && prop->opaque == child) {
+ g_hash_table_iter_remove(&iter);
break;
}
}
@@ -665,10 +698,12 @@ static int do_object_child_foreach(Object *obj,
int (*fn)(Object *child, void *opaque),
void *opaque, bool recurse)
{
- ObjectProperty *prop, *next;
+ GHashTableIter iter;
+ ObjectProperty *prop;
int ret = 0;
- QTAILQ_FOREACH_SAFE(prop, &obj->properties, node, next) {
+ g_hash_table_iter_init(&iter, obj->properties);
+ while (g_hash_table_iter_next(&iter, NULL, (gpointer *)&prop)) {
if (object_property_is_child(prop)) {
Object *child = prop->opaque;
@@ -765,13 +800,11 @@ object_property_add(Object *obj, const char *name, const char *type,
return ret;
}
- QTAILQ_FOREACH(prop, &obj->properties, node) {
- if (strcmp(prop->name, name) == 0) {
- error_setg(errp, "attempt to add duplicate property '%s'"
+ if (g_hash_table_lookup(obj->properties, name) != NULL) {
+ error_setg(errp, "attempt to add duplicate property '%s'"
" to object (type '%s')", name,
object_get_typename(obj));
- return NULL;
- }
+ return NULL;
}
prop = g_malloc0(sizeof(*prop));
@@ -784,7 +817,7 @@ object_property_add(Object *obj, const char *name, const char *type,
prop->release = release;
prop->opaque = opaque;
- QTAILQ_INSERT_TAIL(&obj->properties, prop, node);
+ g_hash_table_insert(obj->properties, prop->name, prop);
return prop;
}
@@ -793,10 +826,9 @@ ObjectProperty *object_property_find(Object *obj, const char *name,
{
ObjectProperty *prop;
- QTAILQ_FOREACH(prop, &obj->properties, node) {
- if (strcmp(prop->name, name) == 0) {
- return prop;
- }
+ prop = g_hash_table_lookup(obj->properties, name);
+ if (prop) {
+ return prop;
}
error_setg(errp, "Property '.%s' not found", name);
@@ -806,7 +838,7 @@ ObjectProperty *object_property_find(Object *obj, const char *name,
ObjectPropertyIterator *object_property_iter_init(Object *obj)
{
ObjectPropertyIterator *ret = g_new0(ObjectPropertyIterator, 1);
- ret->next = QTAILQ_FIRST(&obj->properties);
+ g_hash_table_iter_init(&ret->iter, obj->properties);
return ret;
}
@@ -820,17 +852,19 @@ void object_property_iter_free(ObjectPropertyIterator *iter)
ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter)
{
- ObjectProperty *ret = iter->next;
- if (ret) {
- iter->next = QTAILQ_NEXT(iter->next, node);
+ gpointer key, val;
+ if (!g_hash_table_iter_next(&iter->iter, &key, &val)) {
+ return NULL;
}
- return ret;
+ return val;
}
void object_property_del(struct uc_struct *uc, Object *obj, const char *name, Error **errp)
{
- ObjectProperty *prop = object_property_find(obj, name, errp);
- if (prop == NULL) {
+ ObjectProperty *prop = g_hash_table_lookup(obj->properties, name);
+
+ if (!prop) {
+ error_setg(errp, "Property '.%s' not found", name);
return;
}
@@ -838,12 +872,7 @@ void object_property_del(struct uc_struct *uc, Object *obj, const char *name, Er
prop->release(uc, obj, name, prop->opaque);
}
- QTAILQ_REMOVE(&obj->properties, prop, node);
-
- g_free(prop->name);
- g_free(prop->type);
- g_free(prop->description);
- g_free(prop);
+ g_hash_table_remove(obj->properties, name);
}
void object_property_get(struct uc_struct *uc, Object *obj, Visitor *v, const char *name,
@@ -1248,11 +1277,13 @@ out:
gchar *object_get_canonical_path_component(Object *obj)
{
ObjectProperty *prop = NULL;
+ GHashTableIter iter;
g_assert(obj);
g_assert(obj->parent != NULL);
- QTAILQ_FOREACH(prop, &obj->parent->properties, node) {
+ g_hash_table_iter_init(&iter, obj->parent->properties);
+ while (g_hash_table_iter_next(&iter, NULL, (gpointer *)&prop)) {
if (!object_property_is_child(prop)) {
continue;
}
@@ -1336,11 +1367,13 @@ static Object *object_resolve_partial_path(struct uc_struct *uc, Object *parent,
bool *ambiguous)
{
Object *obj;
+ GHashTableIter iter;
ObjectProperty *prop;
obj = object_resolve_abs_path(uc, parent, parts, typename, 0);
- QTAILQ_FOREACH(prop, &parent->properties, node) {
+ g_hash_table_iter_init(&iter, parent->properties);
+ while (g_hash_table_iter_next(&iter, NULL, (gpointer *)&prop)) {
Object *found;
if (!object_property_is_child(prop)) {