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-rw-r--r--alloc.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/alloc.c b/alloc.c
new file mode 100644
index 000000000..216c23a6f
--- /dev/null
+++ b/alloc.c
@@ -0,0 +1,76 @@
+/*
+ * alloc.c - specialized allocator for internal objects
+ *
+ * Copyright (C) 2006 Linus Torvalds
+ *
+ * The standard malloc/free wastes too much space for objects, partly because
+ * it maintains all the allocation infrastructure (which isn't needed, since
+ * we never free an object descriptor anyway), but even more because it ends
+ * up with maximal alignment because it doesn't know what the object alignment
+ * for the new allocation is.
+ */
+#include "cache.h"
+#include "object.h"
+#include "blob.h"
+#include "tree.h"
+#include "commit.h"
+#include "tag.h"
+
+#define BLOCKING 1024
+
+#define DEFINE_ALLOCATOR(name, type) \
+static unsigned int name##_allocs; \
+void *alloc_##name##_node(void) \
+{ \
+ static int nr; \
+ static type *block; \
+ void *ret; \
+ \
+ if (!nr) { \
+ nr = BLOCKING; \
+ block = xmalloc(BLOCKING * sizeof(type)); \
+ } \
+ nr--; \
+ name##_allocs++; \
+ ret = block++; \
+ memset(ret, 0, sizeof(type)); \
+ return ret; \
+}
+
+union any_object {
+ struct object object;
+ struct blob blob;
+ struct tree tree;
+ struct commit commit;
+ struct tag tag;
+};
+
+DEFINE_ALLOCATOR(blob, struct blob)
+DEFINE_ALLOCATOR(tree, struct tree)
+DEFINE_ALLOCATOR(commit, struct commit)
+DEFINE_ALLOCATOR(tag, struct tag)
+DEFINE_ALLOCATOR(object, union any_object)
+
+#ifdef NO_C99_FORMAT
+#define SZ_FMT "%u"
+#else
+#define SZ_FMT "%zu"
+#endif
+
+static void report(const char* name, unsigned int count, size_t size)
+{
+ fprintf(stderr, "%10s: %8u (" SZ_FMT " kB)\n", name, count, size);
+}
+
+#undef SZ_FMT
+
+#define REPORT(name) \
+ report(#name, name##_allocs, name##_allocs*sizeof(struct name) >> 10)
+
+void alloc_report(void)
+{
+ REPORT(blob);
+ REPORT(tree);
+ REPORT(commit);
+ REPORT(tag);
+}