1 files changed, 174 insertions, 0 deletions
diff --git a/libglusterfs/src/mem-pool.c b/libglusterfs/src/mem-pool.c
new file mode 100644
index 00000000000..c3646f35023
--- /dev/null
+++ b/libglusterfs/src/mem-pool.c
@@ -0,0 +1,174 @@
+/*
+   Copyright (c) 2008 Z RESEARCH, Inc. <http://www.zresearch.com>
+   This file is part of GlusterFS.
+
+   GlusterFS 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 3 of the License,
+   or (at your option) any later version.
+
+   GlusterFS 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, see
+   <http://www.gnu.org/licenses/>.
+*/
+
+#include "mem-pool.h"
+#include "logging.h"
+#include <stdlib.h>
+
+
+#define GF_MEM_POOL_PAD_BOUNDRY    16
+
+
+struct mem_pool *
+mem_pool_new_fn (unsigned long sizeof_type,
+		 unsigned long count)
+{
+	struct mem_pool  *mem_pool = NULL;
+	int               pad = 0;
+	unsigned long     padded_sizeof_type = 0;
+	void             *pool = NULL;
+	int               i = 0;
+	struct list_head *list = NULL;
+  
+	if (!sizeof_type || !count) {
+		gf_log ("mem-pool", GF_LOG_ERROR, "invalid argument");
+		return NULL;
+	}
+  
+	pad = GF_MEM_POOL_PAD_BOUNDRY -
+		(sizeof_type % GF_MEM_POOL_PAD_BOUNDRY);
+	padded_sizeof_type = sizeof_type + pad;
+  
+	mem_pool = CALLOC (sizeof (*mem_pool), 1);
+	if (!mem_pool)
+		return NULL;
+
+	LOCK_INIT (&mem_pool->lock);
+	INIT_LIST_HEAD (&mem_pool->list);
+
+	mem_pool->padded_sizeof_type = padded_sizeof_type;
+	mem_pool->cold_count = count;
+
+	pool = CALLOC (count, sizeof_type + pad);
+	if (!pool)
+		return NULL;
+
+	for (i = 0; i < count; i++) {
+		list = pool + (i * (sizeof_type + pad));
+		INIT_LIST_HEAD (list);
+		list_add_tail (list, &mem_pool->list);
+	}
+
+	mem_pool->pool = pool;
+	mem_pool->pool_end = pool + (count * (sizeof_type + pad));
+
+	return mem_pool;
+}
+
+
+void *
+mem_get (struct mem_pool *mem_pool)
+{
+	struct list_head *list = NULL;
+	void             *ptr = NULL;
+  
+	if (!mem_pool) {
+		gf_log ("mem-pool", GF_LOG_ERROR, "invalid argument");
+		return NULL;
+	}
+
+	LOCK (&mem_pool->lock);
+	{
+		if (mem_pool->cold_count) {
+			list = mem_pool->list.next;
+			list_del (list);
+
+			mem_pool->hot_count++;
+			mem_pool->cold_count--;
+
+			ptr = list;
+		}
+	}
+	UNLOCK (&mem_pool->lock);
+
+	if (ptr == NULL) {
+		ptr = MALLOC (mem_pool->padded_sizeof_type);
+
+		if (!ptr) {
+			return NULL;
+		}
+
+		LOCK (&mem_pool->lock);
+		{
+			mem_pool->hot_count ++;
+		}
+		UNLOCK (&mem_pool->lock);
+	}
+
+	return ptr;
+}
+
+
+static int
+__is_member (struct mem_pool *pool, void *ptr)
+{
+	if (!pool || !ptr) {
+		gf_log ("mem-pool", GF_LOG_ERROR, "invalid argument");
+		return -1;
+	}
+  
+	if (ptr < pool->pool || ptr >= pool->pool_end)
+		return 0;
+
+	if ((ptr - pool->pool) % pool->padded_sizeof_type)
+		return -1;
+
+	return 1;
+}
+
+
+void
+mem_put (struct mem_pool *pool, void *ptr)
+{
+	struct list_head *list = NULL;
+  
+	if (!pool || !ptr) {
+		gf_log ("mem-pool", GF_LOG_ERROR, "invalid argument");
+		return;
+	}
+  
+	list = ptr;
+  
+	LOCK (&pool->lock);
+	{
+		pool->hot_count--;
+
+		switch (__is_member (pool, ptr))
+		{
+		case 1:
+			pool->cold_count++;
+			list_add (list, &pool->list);
+			break;
+		case -1:
+			/* log error */
+			abort ();
+			break;
+		case 0:
+			free (ptr);
+			break;
+		default:
+			/* log error */
+			break;
+		}
+	}
+	UNLOCK (&pool->lock);
+
+	if (ptr)
+		free (ptr);
+}