[Qemu-devel] [RFC V2 14/16] qcow2: Add qcow2_dedup_update_metrics to compute dedup RAM usage.

[Benoît Canet]

---
 block/qcow2-dedup.c |   11 +++++++++++
 block/qcow2.h       |   18 ++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/block/qcow2-dedup.c b/block/qcow2-dedup.c
index 308b4f6..72ce1d7 100644
--- a/block/qcow2-dedup.c
+++ b/block/qcow2-dedup.c
@@ -1311,3 +1311,14 @@ void qcow2_dedup_close(BlockDriverState *bs)
 {
     qcow2_dedup_free(bs);
 }
+
+void qcow2_dedup_update_metrics(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+
+    uint64_t nb_hashs = s->dedup_metrics.ram_hash_creations -
+                        s->dedup_metrics.ram_hash_deletions;
+
+    s->dedup_metrics.ram_usage = nb_hashs * sizeof(GTreeNode_Copy) * 2;
+    s->dedup_metrics.ram_usage += nb_hashs * sizeof(QCowHashNode);
+}
diff --git a/block/qcow2.h b/block/qcow2.h
index fc393d5..191b272 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -76,6 +76,23 @@
 #define QCOW_STRATEGY_DISK    (1 << 1)
 #define QCOW_STRATEGY_RUNNING (1 << 2)
 
+/* This is an internal structure of glib gtree.c
+ * copy it here so we can compute it's size
+ * from glib/gtree.c in glib sources
+ */
+typedef struct _GTreeNode_Copy  GTreeNode_Copy;
+
+struct _GTreeNode_Copy
+{
+  gpointer   key;         /* key for this node */
+  gpointer   value;       /* value stored at this node */
+  GTreeNode_Copy *left;  /* left subtree */
+  GTreeNode_Copy *right; /* right subtree */
+  gint8      balance;     /* height (right) - height (left) */
+  guint8     left_child;
+  guint8     right_child;
+};
+
 typedef enum {
     QCOW_HASH_SHA256 = 0,
     QCOW_HASH_SHA3   = 1,
@@ -507,5 +524,6 @@ void qcow2_dedup_refcount_half_max_reached(BlockDriverState 
*bs,
 bool qcow2_dedup_is_running(BlockDriverState *bs);
 int qcow2_dedup_init(BlockDriverState *bs);
 void qcow2_dedup_close(BlockDriverState *bs);
+void qcow2_dedup_update_metrics(BlockDriverState *bs);
 
 #endif
-- 
1.7.10.4