libgo/runtime/mheapmap32.h

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // Free(v) must be able to determine the MSpan containing v.
   6 // The MHeapMap is a 2-level radix tree mapping page numbers to MSpans.
   7
   8 typedef struct MHeapMapNode2 MHeapMapNode2;
   9
  10 enum
  11 {
  12         // 32 bit address - 12 bit page size = 20 bits to map
  13         MHeapMap_Level1Bits = 10,
  14         MHeapMap_Level2Bits = 10,
  15
  16         MHeapMap_TotalBits =
  17                 MHeapMap_Level1Bits +
  18                 MHeapMap_Level2Bits,
  19
  20         MHeapMap_Level1Mask = (1<<MHeapMap_Level1Bits) - 1,
  21         MHeapMap_Level2Mask = (1<<MHeapMap_Level2Bits) - 1,
  22 };
  23
  24 struct MHeapMap
  25 {
  26         void *(*allocator)(uintptr);
  27         MHeapMapNode2 *p[1<<MHeapMap_Level1Bits];
  28 };
  29
  30 struct MHeapMapNode2
  31 {
  32         MSpan *s[1<<MHeapMap_Level2Bits];
  33 };
  34
  35 void    runtime_MHeapMap_Init(MHeapMap *m, void *(*allocator)(uintptr));
  36 bool    runtime_MHeapMap_Preallocate(MHeapMap *m, PageID k, uintptr npages);
  37 MSpan*  runtime_MHeapMap_Get(MHeapMap *m, PageID k);
  38 MSpan*  runtime_MHeapMap_GetMaybe(MHeapMap *m, PageID k);
  39 void    runtime_MHeapMap_Set(MHeapMap *m, PageID k, MSpan *v);
  40
  41