better binning of Average stats

base/statistics.hh:
    Try to make binning of Average statistics work a little better.
    This solution is far from perfect though since we really need
    to call set(p.current, p) when the binning takes place.

    To fix the binning, we need to have the current value non-binned,
    to do that, we make make the current value part of the Params struct.
    This means that we can't pass around const Params structs

    Maybe we need a binswap callback :/

--HG--
extra : convert_revision : c2892387dbabe011bdcd6f0d99005c1c50653720

1 files changed, 61 insertions, 29 deletions

diff --git a/base/statistics.hh b/base/statistics.hh
index f71e24672..f6c421fb5 100644
--- a/base/statistics.hh
+++ b/base/statistics.hh
@@ -467,12 +467,17 @@ template <typename T>
 struct AvgStor
 {
   public:
-    /** The paramaters for this storage type, none for this average. */
-    struct Params { };
+    /** The paramaters for this storage type */
+    struct Params
+    {
+        /**
+         * The current count.  We stash this here because the current
+         * value is not a binned value.
+         */
+        T current;
+    };
 
   private:
-    /** The current count. */
-    T current;
     /** The total count for all cycles. */
     mutable result_t total;
     /** The cycle that current last changed. */
@@ -482,7 +487,7 @@ struct AvgStor
     /**
      * Build and initializes this stat storage.
      */
-    AvgStor(const Params &) : current(T()), total(0), last(0) { }
+    AvgStor(Params &p) : total(0), last(0) { p.current = T(); }
 
     /**
      * Set the current count to the one provided, update the total and last
@@ -490,39 +495,44 @@ struct AvgStor
      * @param val The new count.
      * @param p The parameters for this storage.
      */
-    void set(T val, const Params &p) {
-        total += current * (curTick - last);
+    void set(T val, Params &p) {
+        total += p.current * (curTick - last);
         last = curTick;
-        current = val;
+        p.current = val;
     }
+
     /**
      * Increment the current count by the provided value, calls set.
      * @param val The amount to increment.
      * @param p The parameters for this storage.
      */
-    void inc(T val, const Params &p) { set(current + val, p); }
+    void inc(T val, Params &p) { set(p.current + val, p); }
+
     /**
      * Deccrement the current count by the provided value, calls set.
      * @param val The amount to decrement.
      * @param p The parameters for this storage.
      */
-    void dec(T val, const Params &p) { set(current - val, p); }
+    void dec(T val, Params &p) { set(p.current - val, p); }
+
     /**
      * Return the current average.
      * @param p The parameters for this storage.
      * @return The current average.
      */
     result_t val(const Params &p) const {
-        total += current * (curTick - last);
+        total += p.current * (curTick - last);
         last = curTick;
-        return (result_t)(total + current) / (result_t)(curTick + 1);
+        return (result_t)(total + p.current) / (result_t)(curTick + 1);
     }
+
     /**
      * Return the current count.
      * @param p The parameters for this storage.
      * @return The current count.
      */
-    T value(const Params &p) const { return current; }
+    T value(const Params &p) const { return p.current; }
+
     /**
      * Reset stat value to default
      */
@@ -565,8 +575,11 @@ class ScalarBase : public ScalarStat
      * Retrieve a const pointer to the storage from the bin.
      * @return A const pointer to the storage object for this stat.
      */
-    const storage_t *data() const {
-        return (const_cast<bin_t *>(&bin))->data(params);
+    const storage_t *data() const
+    {
+        bin_t *_bin = const_cast<bin_t *>(&bin);
+        params_t *_params = const_cast<params_t *>(&params);
+        return _bin->data(*_params);
     }
 
   protected:
@@ -705,8 +718,11 @@ class VectorBase : public VectorStat
      * @param index The vector index to access.
      * @return A const pointer to the storage object at the given index.
      */
-    const storage_t *data(int index) const {
-        return (const_cast<bin_t *>(&bin))->data(index, params);
+    const storage_t *data(int index) const
+    {
+        bin_t *_bin = const_cast<bin_t *>(&bin);
+        params_t *_params = const_cast<params_t *>(&params);
+        return _bin->data(index, *_params);
     }
 
   protected:
@@ -825,7 +841,12 @@ class ScalarProxy : public ScalarStat
      * Retrieve a const pointer to the storage from the bin.
      * @return A const pointer to the storage for this stat.
      */
-    const storage_t *data() const { return bin->data(index, *params); }
+    const storage_t *data() const
+    {
+        bin_t *_bin = const_cast<bin_t *>(bin);
+        params_t *_params = const_cast<params_t *>(params);
+        return _bin->data(index, *_params);
+    }
 
   public:
     /**
@@ -952,8 +973,11 @@ class Vector2dBase : public Stat
 
   protected:
     storage_t *data(int index) { return bin.data(index, params); }
-    const storage_t *data(int index) const {
-        return (const_cast<bin_t *>(&bin))->data(index, params);
+    const storage_t *data(int index) const
+    {
+        bin_t *_bin = const_cast<bin_t *>(&bin);
+        params_t *_params = const_cast<params_t *>(&params);
+        return _bin->data(index, *_params);
     }
 
   protected:
@@ -1081,7 +1105,9 @@ class VectorProxy : public VectorStat
     }
 
     const storage_t *data(int index) const {
-        return (const_cast<bin_t *>(bin))->data(offset + index, *params);
+        bin_t *_bin = const_cast<bin_t *>(bin);
+        params_t *_params = const_cast<params_t *>(params);
+        return _bin->data(offset + index, *_params);
     }
 
   public:
@@ -1506,8 +1532,11 @@ class DistBase : public Stat
      * Retrieve a const pointer to the storage from the bin.
      * @return A const pointer to the storage object for this stat.
      */
-    const storage_t *data() const {
-        return (const_cast<bin_t *>(&bin))->data(params);
+    const storage_t *data() const
+    {
+        bin_t *_bin = const_cast<bin_t *>(&bin);
+        params_t *_params = const_cast<params_t *>(&params);
+        return _bin->data(*_params);
     }
 
   protected:
@@ -1585,8 +1614,11 @@ class VectorDistBase : public Stat
 
   protected:
     storage_t *data(int index) { return bin.data(index, params); }
-    const storage_t *data(int index) const {
-        return (const_cast<bin_t *>(&bin))->data(index, params);
+    const storage_t *data(int index) const
+    {
+        bin_t *_bin = const_cast<bin_t *>(&bin);
+        params_t *_params = const_cast<params_t *>(&params);
+        return _bin->data(index, *_params);
     }
 
   protected:
@@ -2252,7 +2284,7 @@ struct StatBin : public GenBin
 
         int size() const { return 1; }
 
-        Storage *data(const Params &params) {
+        Storage *data(Params &params) {
             assert(initialized());
             char *ptr = access();
             char *flags = ptr + sizeof(Storage);
@@ -2297,7 +2329,7 @@ struct StatBin : public GenBin
 
         int size() const { return _size; }
 
-        Storage *data(int index, const Params &params) {
+        Storage *data(int index, Params &params) {
             assert(initialized());
             assert(index >= 0 && index < size());
             char *ptr = access();
@@ -2351,7 +2383,7 @@ struct NoBin
             new (ptr) Storage(params);
         }
         int size() const{ return 1; }
-        Storage *data(const Params &params) {
+        Storage *data(Params &params) {
             assert(initialized());
             return reinterpret_cast<Storage *>(ptr);
         }
@@ -2399,7 +2431,7 @@ struct NoBin
 
         int size() const { return _size; }
 
-        Storage *data(int index, const Params &params) {
+        Storage *data(int index, Params &params) {
             assert(initialized());
             assert(index >= 0 && index < size());
             return reinterpret_cast<Storage *>(ptr + index * sizeof(Storage));