1 files changed, 169 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/util/u_slab.c b/src/gallium/auxiliary/util/u_slab.c
new file mode 100644
index 0000000000..21bf2d735a
--- /dev/null
+++ b/src/gallium/auxiliary/util/u_slab.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright 2010 Marek Olšák <maraeo@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * on the rights to use, copy, modify, merge, publish, distribute, sub
+ * license, and/or sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE. */
+
+#include "util/u_slab.h"
+
+#include "util/u_math.h"
+#include "util/u_memory.h"
+#include "util/u_simple_list.h"
+
+#include <stdio.h>
+
+#define UTIL_SLAB_MAGIC 0xcafe4321
+
+/* The block is either allocated memory or free space. */
+struct util_slab_block {
+   /* The header. */
+   /* The first next free block. */
+   struct util_slab_block *next_free;
+
+   intptr_t magic;
+
+   /* Memory after the last member is dedicated to the block itself.
+    * The allocated size is always larger than this structure. */
+};
+
+static struct util_slab_block *
+util_slab_get_block(struct util_slab_mempool *pool,
+                    struct util_slab_page *page, unsigned index)
+{
+   return (struct util_slab_block*)
+          ((uint8_t*)page + sizeof(struct util_slab_page) +
+           (pool->block_size * index));
+}
+
+static void util_slab_add_new_page(struct util_slab_mempool *pool)
+{
+   struct util_slab_page *page;
+   struct util_slab_block *block;
+   int i;
+
+   page = MALLOC(pool->page_size);
+   insert_at_tail(&pool->list, page);
+
+   /* Mark all blocks as free. */
+   for (i = 0; i < pool->num_blocks-1; i++) {
+      block = util_slab_get_block(pool, page, i);
+      block->next_free = util_slab_get_block(pool, page, i+1);
+      block->magic = UTIL_SLAB_MAGIC;
+   }
+
+   block = util_slab_get_block(pool, page, pool->num_blocks-1);
+   block->next_free = pool->first_free;
+   block->magic = UTIL_SLAB_MAGIC;
+   pool->first_free = util_slab_get_block(pool, page, 0);
+   pool->num_pages++;
+
+#if 0
+   fprintf(stderr, "New page! Num of pages: %i\n", pool->num_pages);
+#endif
+}
+
+static void *util_slab_alloc_st(struct util_slab_mempool *pool)
+{
+   struct util_slab_block *block;
+
+   if (!pool->first_free)
+      util_slab_add_new_page(pool);
+
+   block = pool->first_free;
+   assert(block->magic == UTIL_SLAB_MAGIC);
+   pool->first_free = block->next_free;
+
+   return (uint8_t*)block + sizeof(struct util_slab_block);
+}
+
+static void util_slab_free_st(struct util_slab_mempool *pool, void *ptr)
+{
+   struct util_slab_block *block =
+         (struct util_slab_block*)
+         ((uint8_t*)ptr - sizeof(struct util_slab_block));
+
+   assert(block->magic == UTIL_SLAB_MAGIC);
+   block->next_free = pool->first_free;
+   pool->first_free = block;
+}
+
+static void *util_slab_alloc_mt(struct util_slab_mempool *pool)
+{
+   void *mem;
+
+   pipe_mutex_lock(pool->mutex);
+   mem = util_slab_alloc_st(pool);
+   pipe_mutex_unlock(pool->mutex);
+   return mem;
+}
+
+static void util_slab_free_mt(struct util_slab_mempool *pool, void *ptr)
+{
+   pipe_mutex_lock(pool->mutex);
+   util_slab_free_st(pool, ptr);
+   pipe_mutex_unlock(pool->mutex);
+}
+
+void util_slab_set_thread_safety(struct util_slab_mempool *pool,
+                                    enum util_slab_threading threading)
+{
+   pool->threading = threading;
+
+   if (threading) {
+      pool->alloc = util_slab_alloc_mt;
+      pool->free = util_slab_free_mt;
+   } else {
+      pool->alloc = util_slab_alloc_st;
+      pool->free = util_slab_free_st;
+   }
+}
+
+void util_slab_create(struct util_slab_mempool *pool,
+                      unsigned item_size,
+                      unsigned num_blocks,
+                      enum util_slab_threading threading)
+{
+   item_size = align(item_size, sizeof(intptr_t));
+
+   pool->num_pages = 0;
+   pool->num_blocks = num_blocks;
+   pool->block_size = sizeof(struct util_slab_block) + item_size;
+   pool->block_size = align(pool->block_size, sizeof(intptr_t));
+   pool->page_size = sizeof(struct util_slab_page) +
+                     num_blocks * pool->block_size;
+   pool->first_free = NULL;
+
+   make_empty_list(&pool->list);
+
+   pipe_mutex_init(pool->mutex);
+
+   util_slab_set_thread_safety(pool, threading);
+}
+
+void util_slab_destroy(struct util_slab_mempool *pool)
+{
+   struct util_slab_page *page, *temp;
+
+   foreach_s(page, temp, &pool->list) {
+      remove_from_list(page);
+      FREE(page);
+   }
+
+   pipe_mutex_destroy(pool->mutex);
+}