Andrew's git - gitweb.git/blob

   1/*
   2 * alloc.c  - specialized allocator for internal objects
   3 *
   4 * Copyright (C) 2006 Linus Torvalds
   5 *
   6 * The standard malloc/free wastes too much space for objects, partly because
   7 * it maintains all the allocation infrastructure (which isn't needed, since
   8 * we never free an object descriptor anyway), but even more because it ends
   9 * up with maximal alignment because it doesn't know what the object alignment
  10 * for the new allocation is.
  11 */
  12#include "cache.h"
  13#include "object.h"
  14#include "blob.h"
  15#include "tree.h"
  16#include "commit.h"
  17#include "tag.h"
  18
  19#define BLOCKING 1024
  20
  21#define DEFINE_ALLOCATOR(name)                                  \
  22static unsigned int name##_allocs;                              \
  23struct name *alloc_##name##_node(void)                          \
  24{                                                               \
  25        static int nr;                                          \
  26        static struct name *block;                              \
  27                                                                \
  28        if (!nr) {                                              \
  29                nr = BLOCKING;                                  \
  30                block = xcalloc(BLOCKING, sizeof(struct name)); \
  31        }                                                       \
  32        nr--;                                                   \
  33        name##_allocs++;                                        \
  34        return block++;                                         \
  35}
  36
  37DEFINE_ALLOCATOR(blob)
  38DEFINE_ALLOCATOR(tree)
  39DEFINE_ALLOCATOR(commit)
  40DEFINE_ALLOCATOR(tag)
  41
  42#ifdef NO_C99_FORMAT
  43#define SZ_FMT "%u"
  44#else
  45#define SZ_FMT "%zu"
  46#endif
  47
  48static void report(const char* name, unsigned int count, size_t size)
  49{
  50    fprintf(stderr, "%10s: %8u (" SZ_FMT " kB)\n", name, count, size);
  51}
  52
  53#undef SZ_FMT
  54
  55#define REPORT(name)    \
  56    report(#name, name##_allocs, name##_allocs*sizeof(struct name) >> 10)
  57
  58void alloc_report(void)
  59{
  60        REPORT(blob);
  61        REPORT(tree);
  62        REPORT(commit);
  63        REPORT(tag);
  64}