--- /dev/null
+/* -*- mode: C; c-basic-offset: 3; -*- */
+/*
+ This file is part of drd, a thread error detector.
+
+ Copyright (C) 2006-2009 Bart Van Assche <bart.vanassche@gmail.com>.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307, USA.
+
+ The GNU General Public License is contained in the file COPYING.
+*/
+
+/*
+ * Block allocator for second-level bitmap nodes. Each node consists of
+ * an OSetGen node and a struct bitmap2. The code below allocates
+ * NODES_PER_CHUNK nodes at a time.
+ */
+
+
+#include "drd_basics.h" /* DRD_() */
+#include "drd_bitmap.h" /* struct bitmap2 */
+#include "pub_drd_bitmap.h"
+#include "pub_tool_basics.h" /* Addr, SizeT */
+#include "pub_tool_libcassert.h" /* tl_assert() */
+#include "pub_tool_libcbase.h" /* VG_ROUNDUP() */
+#include "pub_tool_libcprint.h" /* VG_(message)() */
+#include "pub_tool_mallocfree.h" /* VG_(malloc), VG_(free) */
+
+
+#define NODES_PER_CHUNCK 512
+
+
+/* Local type definitions. */
+
+struct block_allocator_chunk {
+ struct block_allocator_chunk* next;
+ struct block_allocator_chunk* prev;
+ int nallocated;
+ void* data;
+ void* data_end;
+ void* first_free;
+};
+
+
+/* Local variables. */
+
+static SizeT s_bm2_node_size;
+static struct block_allocator_chunk* s_first;
+
+
+/* Function definitions. */
+
+/**
+ * Allocate a new chunk and insert it at the start of the doubly-linked list
+ * s_first.
+ */
+static struct block_allocator_chunk* allocate_new_chunk(void)
+{
+ struct block_allocator_chunk* p;
+ int i;
+
+ tl_assert(s_bm2_node_size > 0);
+
+ p = VG_(malloc)("drd.bitmap.bac",
+ sizeof(*p) + NODES_PER_CHUNCK * s_bm2_node_size);
+ tl_assert(p);
+ p->next = s_first;
+ if (s_first)
+ p->next->prev = p;
+ s_first = p;
+ p->prev = 0;
+ p->nallocated = 0;
+ p->data = (char*)p + sizeof(*p);
+ tl_assert(p->data);
+ p->data_end = (char*)(p->data) + NODES_PER_CHUNCK * s_bm2_node_size;
+ p->first_free = p->data;
+ for (i = 0; i < NODES_PER_CHUNCK - 1; i++)
+ {
+ *(void**)((char*)(p->data) + i * s_bm2_node_size)
+ = (char*)(p->data) + (i + 1) * s_bm2_node_size;
+ }
+ tl_assert(i == NODES_PER_CHUNCK - 1);
+ *(void**)((char*)(p->data) + i * s_bm2_node_size) = NULL;
+
+ return p;
+}
+
+/** Free a chunk and remove it from the list of chunks. */
+static void free_chunk(struct block_allocator_chunk* const p)
+{
+ tl_assert(p);
+ tl_assert(p->nallocated == 0);
+
+ if (p == s_first)
+ s_first = p->next;
+ else if (p->prev)
+ p->prev->next = p->next;
+ if (p->next)
+ p->next->prev = p->prev;
+ VG_(free)(p);
+}
+
+/** Allocate a node. */
+void* DRD_(bm2_alloc_node)(HChar* const ec, const SizeT szB)
+{
+ /*
+ * If szB < sizeof(struct bitmap2) then this function has been called to
+ * allocate an AVL tree root node. Otherwise it has been called to allocate
+ * an AVL tree branch or leaf node.
+ */
+ if (szB < sizeof(struct bitmap2))
+ return VG_(malloc)(ec, szB);
+
+ while (True)
+ {
+ struct block_allocator_chunk* p;
+
+ if (s_bm2_node_size == 0)
+ s_bm2_node_size = szB;
+ else
+ tl_assert(s_bm2_node_size == szB);
+
+ for (p = s_first; p; p = p->next)
+ {
+ if (p->first_free)
+ {
+ void* result;
+
+ p->nallocated++;
+ result = p->first_free;
+ p->first_free = *(void**)(p->first_free);
+ return result;
+ }
+ }
+
+ allocate_new_chunk();
+ }
+}
+
+/** Free a node. */
+void DRD_(bm2_free_node)(void* const bm2)
+{
+ struct block_allocator_chunk* p;
+
+ tl_assert(s_bm2_node_size > 0);
+ tl_assert(bm2);
+
+ for (p = s_first; p; p = p->next)
+ {
+ if (p->data <= bm2 && bm2 < p->data_end)
+ {
+ /* Free the memory that was allocated for a non-root AVL tree node. */
+ tl_assert(((char*)bm2 - (char*)(p->data)) % s_bm2_node_size == 0);
+ *(void**)bm2 = p->first_free;
+ p->first_free = bm2;
+ tl_assert(p->nallocated >= 1);
+ if (--(p->nallocated) == 0)
+ free_chunk(p);
+ return;
+ }
+ }
+
+ /* Free the memory that was allocated for an AVL tree root node. */
+ VG_(free)(bm2);
+}
projects / thirdparty / valgrind.git / commitdiff
