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969eba6341
Whenever we create a commit object via lookup_commit, we give it a unique index to be used with the commit-slab API. The theory is that any "struct commit" we create would follow this code path, so any such struct would get an index. However, callers could use alloc_commit_node() directly (and get multiple commits with index 0). Let's push the indexing into alloc_commit_node so that it's hard for callers to get it wrong. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
78 lines
1.9 KiB
C
78 lines
1.9 KiB
C
/*
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* alloc.c - specialized allocator for internal objects
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*
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* Copyright (C) 2006 Linus Torvalds
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*
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* The standard malloc/free wastes too much space for objects, partly because
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* it maintains all the allocation infrastructure (which isn't needed, since
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* we never free an object descriptor anyway), but even more because it ends
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* up with maximal alignment because it doesn't know what the object alignment
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* for the new allocation is.
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*/
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#include "cache.h"
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#include "object.h"
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#include "blob.h"
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#include "tree.h"
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#include "commit.h"
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#include "tag.h"
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#define BLOCKING 1024
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#define DEFINE_ALLOCATOR(name, type) \
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static unsigned int name##_allocs; \
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void *alloc_##name##_node(void) \
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{ \
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static int nr; \
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static type *block; \
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void *ret; \
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\
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if (!nr) { \
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nr = BLOCKING; \
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block = xmalloc(BLOCKING * sizeof(type)); \
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} \
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nr--; \
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name##_allocs++; \
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ret = block++; \
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memset(ret, 0, sizeof(type)); \
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return ret; \
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}
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union any_object {
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struct object object;
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struct blob blob;
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struct tree tree;
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struct commit commit;
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struct tag tag;
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};
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DEFINE_ALLOCATOR(blob, struct blob)
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DEFINE_ALLOCATOR(tree, struct tree)
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DEFINE_ALLOCATOR(raw_commit, struct commit)
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DEFINE_ALLOCATOR(tag, struct tag)
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DEFINE_ALLOCATOR(object, union any_object)
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void *alloc_commit_node(void)
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{
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static int commit_count;
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struct commit *c = alloc_raw_commit_node();
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c->index = commit_count++;
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return c;
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}
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static void report(const char *name, unsigned int count, size_t size)
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{
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fprintf(stderr, "%10s: %8u (%"PRIuMAX" kB)\n",
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name, count, (uintmax_t) size);
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}
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#define REPORT(name, type) \
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report(#name, name##_allocs, name##_allocs * sizeof(type) >> 10)
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void alloc_report(void)
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{
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REPORT(blob, struct blob);
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REPORT(tree, struct tree);
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REPORT(raw_commit, struct commit);
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REPORT(tag, struct tag);
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REPORT(object, union any_object);
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}
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