struct list_head list;
};
+/*
+ * A callchain cursor is a single linked list that
+ * let one feed a callchain progressively.
+ * It keeps persitent allocated entries to minimize
+ * allocations.
+ */
+struct callchain_cursor_node {
+ u64 ip;
+ struct map *map;
+ struct symbol *sym;
+ struct callchain_cursor_node *next;
+};
+
+struct callchain_cursor {
+ u64 nr;
+ struct callchain_cursor_node *first;
+ struct callchain_cursor_node **last;
+ u64 pos;
+ struct callchain_cursor_node *curr;
+};
+
static inline void callchain_init(struct callchain_root *root)
{
INIT_LIST_HEAD(&root->node.brothers);
}
int register_callchain_param(struct callchain_param *param);
-int callchain_append(struct callchain_root *root, struct ip_callchain *chain,
- struct map_symbol *syms, u64 period);
-int callchain_merge(struct callchain_root *dst, struct callchain_root *src);
+int callchain_append(struct callchain_root *root,
+ struct callchain_cursor *cursor,
+ u64 period);
+
+int callchain_merge(struct callchain_cursor *cursor,
+ struct callchain_root *dst, struct callchain_root *src);
bool ip_callchain__valid(struct ip_callchain *chain, const event_t *event);
+
+/*
+ * Initialize a cursor before adding entries inside, but keep
+ * the previously allocated entries as a cache.
+ */
+static inline void callchain_cursor_reset(struct callchain_cursor *cursor)
+{
+ cursor->nr = 0;
+ cursor->last = &cursor->first;
+}
+
+int callchain_cursor_append(struct callchain_cursor *cursor, u64 ip,
+ struct map *map, struct symbol *sym);
+
+/* Close a cursor writing session. Initialize for the reader */
+static inline void callchain_cursor_commit(struct callchain_cursor *cursor)
+{
+ cursor->curr = cursor->first;
+ cursor->pos = 0;
+}
+
+/* Cursor reading iteration helpers */
+static inline struct callchain_cursor_node *
+callchain_cursor_current(struct callchain_cursor *cursor)
+{
+ if (cursor->pos == cursor->nr)
+ return NULL;
+
+ return cursor->curr;
+}
+
+static inline void callchain_cursor_advance(struct callchain_cursor *cursor)
+{
+ cursor->curr = cursor->curr->next;
+ cursor->pos++;
+}
#endif /* __PERF_CALLCHAIN_H */