Improve cake allocator's memory utilisation (#43)

[lunaix-os.git] / lunaix-os / kernel / mm / valloc.c

diff --git a/lunaix-os/kernel/mm/valloc.c b/lunaix-os/kernel/mm/valloc.c
index 67c8eacb3f43f45b8b68c421e72c5f157c33583e..d2baa352b05ee81f231b0739c75caa022ec175b4 100644 (file)
--- a/lunaix-os/kernel/mm/valloc.c
+++ b/lunaix-os/kernel/mm/valloc.c
@@ -5,6 +5,9 @@
 
 #define CLASS_LEN(class) (sizeof(class) / sizeof(class[0]))
 
+// threshold to use external cake metadata
+#define EXTERN_THRESHOLD    128
+
 static char piles_names[][PILE_NAME_MAXLEN] = 
 {
     "valloc_8",   "valloc_16",  "valloc_32",  "valloc_64",
@@ -12,6 +15,24 @@ static char piles_names[][PILE_NAME_MAXLEN] =
     "valloc_2k",  "valloc_4k",  "valloc_8k"  
 };
 
+#define M128    (4)
+#define M1K     (M128 + 3)
+
+static int page_counts[] = 
+{
+    [0] = 1,
+    [1] = 1,
+    [2] = 1,
+    [3] = 1,
+    [M128    ] = 1,
+    [M128 + 1] = 2,
+    [M128 + 2] = 2,
+    [M1K     ] = 4,
+    [M1K + 1 ] = 4,
+    [M1K + 2 ] = 8,
+    [M1K + 3 ] = 8
+};
+
 static char piles_names_dma[][PILE_NAME_MAXLEN] = 
 {
     "valloc_dma_128", "valloc_dma_256", "valloc_dma_512",
@@ -24,16 +45,24 @@ static struct cake_pile* piles_dma[CLASS_LEN(piles_names_dma)];
 void
 valloc_init()
 {
+    int opts = 0;
     for (size_t i = 0; i < CLASS_LEN(piles_names); i++) {
         int size = 1 << (i + 3);
-        piles[i] = cake_new_pile(piles_names[i], size, size > 1024 ? 8 : 1, 0);
+        if (size >= EXTERN_THRESHOLD) {
+            opts |= PILE_FL_EXTERN;
+        }
+        piles[i] = cake_new_pile(piles_names[i], size, page_counts[i], opts);
     }
 
+    opts = PILE_ALIGN_CACHE;
     // DMA 内存保证128字节对齐
     for (size_t i = 0; i < CLASS_LEN(piles_names_dma); i++) {
         int size = 1 << (i + 7);
+        if (size >= EXTERN_THRESHOLD) {
+            opts |= PILE_FL_EXTERN;
+        }
         piles_dma[i] = cake_new_pile(
-            piles_names_dma[i], size, size > 1024 ? 4 : 1, PILE_ALIGN_CACHE);
+            piles_names_dma[i], size, page_counts[M128 + i], opts);
     }
 }