Changeset 37195 in vbox for trunk/src/VBox

Timestamp:

May 24, 2011 2:00:32 PM (14 years ago)

Author:

vboxsync

Message:

GMMR0: Set list selection function (no real change)

File:

• trunk/src/VBox/VMM/VMMR0/GMMR0.cpp (modified) (8 diffs)

trunk/src/VBox/VMM/VMMR0/GMMR0.cpp

@@ -468 +468 @@
 /** The GMMCHUNK::cFree shift count. */
 #define GMM_CHUNK_FREE_SET_SHIFT    4
-/** The GMMCHUNK::cFree mask for use when considering relinking a chunk. */
-#define GMM_CHUNK_FREE_SET_MASK     15
-/** The number of lists in set. */
-#define GMM_CHUNK_FREE_SET_LISTS    (GMM_CHUNK_NUM_PAGES >> GMM_CHUNK_FREE_SET_SHIFT)
 
 
@@ -485 +481 @@
     uint64_t            idGeneration;
     /** Chunks ordered by increasing number of free pages. */
-    PGMMCHUNK           apLists[GMM_CHUNK_FREE_SET_LISTS];
+    PGMMCHUNK           apLists[GMM_CHUNK_NUM_PAGES >> GMM_CHUNK_FREE_SET_SHIFT];
 } GMMCHUNKFREESET;
 
@@ -1706 +1702 @@
 
 /**
+ * Selects the appropriate free list given the number of free pages.
+ *
+ * @returns Free list index.
+ * @param
+ */
+DECLINLINE(unsigned) gmmR0SelectFreeSetList(unsigned cFree)
+{
+    return (cFree - 1) >> GMM_CHUNK_FREE_SET_SHIFT;
+}
+
+
+/**
  * Unlinks the chunk from the free list it's currently on (if any).
  *
@@ -1723 +1731 @@
             pPrev->pFreeNext = pNext;
         else
-            pSet->apLists[(pChunk->cFree - 1) >> GMM_CHUNK_FREE_SET_SHIFT] = pNext;
+            pSet->apLists[gmmR0SelectFreeSetList(pChunk->cFree)] = pNext;
         if (pNext)
             pNext->pFreePrev = pPrev;
@@ -1758 +1766 @@
         pChunk->pSet = pSet;
         pChunk->pFreePrev = NULL;
-        unsigned iList = (pChunk->cFree - 1) >> GMM_CHUNK_FREE_SET_SHIFT;
+        unsigned const iList = gmmR0SelectFreeSetList(pChunk->cFree);
         pChunk->pFreeNext = pSet->apLists[iList];
         if (pChunk->pFreeNext)
@@ -1987 +1995 @@
                &&   pOtherSet->cFreePages >= GMM_CHUNK_NUM_PAGES)
         {
-            PGMMCHUNK pChunk = pOtherSet->apLists[GMM_CHUNK_FREE_SET_LISTS - 1];
+            PGMMCHUNK pChunk = pOtherSet->apLists[RT_ELEMENTS(pOtherSet->apLists) - 1];
             while (pChunk && pChunk->cFree != GMM_CHUNK_NUM_PAGES)
                 pChunk = pChunk->pFreeNext;
@@ -2910 +2918 @@
      * and relink the chunk if necessary.
      */
-    if ((pChunk->cFree & GMM_CHUNK_FREE_SET_MASK) == 0)
+    if (gmmR0SelectFreeSetList(pChunk->cFree) != gmmR0SelectFreeSetList(pChunk->cFree + 1))
     {
         gmmR0UnlinkChunk(pChunk);
@@ -2920 +2928 @@
         pChunk->cFree++;
         pChunk->pSet->cFreePages++;
-
-        /*
-         * If the chunk becomes empty, consider giving memory back to the host OS.
-         *
-         * The current strategy is to try give it back if there are other chunks
-         * in this free list, meaning if there are at least 240 free pages in this
-         * category. Note that since there are probably mappings of the chunk,
-         * it won't be freed up instantly, which probably screws up this logic
-         * a bit...
-         */
-        if (RT_UNLIKELY(   pChunk->cFree == GMM_CHUNK_NUM_PAGES
-                        && pChunk->pFreeNext
-                        && pChunk->pFreePrev /** @todo this is probably misfiring, see reset... */
-                        && !pGMM->fLegacyAllocationMode))
-            gmmR0FreeChunk(pGMM, NULL, pChunk);
-    }
+    }
+
+    /*
+     * If the chunk becomes empty, consider giving memory back to the host OS.
+     *
+     * The current strategy is to try give it back if there are other chunks
+     * in this free list, meaning if there are at least 240 free pages in this
+     * category. Note that since there are probably mappings of the chunk,
+     * it won't be freed up instantly, which probably screws up this logic
+     * a bit...
+     */
+    if (RT_UNLIKELY(   pChunk->cFree == GMM_CHUNK_NUM_PAGES
+                    && pChunk->pFreeNext
+                    && pChunk->pFreePrev /** @todo this is probably misfiring, see reset... */
+                    && !pGMM->fLegacyAllocationMode))
+        gmmR0FreeChunk(pGMM, NULL, pChunk);
+
 }