VILLASnode/lib/pool.c

/** Memory pool for fixed size objects.
 *
 * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
 * @copyright 2017, Institute for Automation of Complex Power Systems, EONERC
 *********************************************************************************/

#include "utils.h"

#include "pool.h"
#include "memory.h"
#include "kernel/kernel.h"

int pool_init(struct pool *p, size_t cnt, size_t blocksz, struct memtype *m)
{
	int ret;
	
	assert(p->state == STATE_DESTROYED);

	/* Make sure that we use a block size that is aligned to the size of a cache line */
	p->alignment = kernel_get_cacheline_size();
	p->blocksz = p->alignment * CEIL(blocksz, p->alignment);
	p->len = cnt * p->blocksz;
	p->mem = m;

	void *buffer = memory_alloc_aligned(m, p->len, p->alignment);
	if (!buffer)
		serror("Failed to allocate memory for memory pool");
	else
		debug(LOG_POOL | 4, "Allocated %#zx bytes for memory pool", p->len);
	p->buffer_off = (char*) buffer - (char*) p;

	ret = queue_init(&p->queue, LOG2_CEIL(cnt), m);
	if (ret)
		return ret;
	
	for (int i = 0; i < cnt; i++)
		queue_push(&p->queue, (char *) buffer + i * p->blocksz);
	
	p->state = STATE_INITIALIZED;

	return 0;
}

int pool_destroy(struct pool *p)
{
	int ret;

	if (p->state == STATE_DESTROYED)
		return 0;

	queue_destroy(&p->queue);	

	void *buffer = (char*) p + p->buffer_off;
	ret = memory_free(p->mem, buffer, p->len);
	if (ret == 0)
		p->state = STATE_DESTROYED;

	return ret;
}