Function sync_existing

dpdk/lib/eal/linux/eal_memalloc.c:1333–1378

}

static int
sync_existing(struct rte_memseg_list *primary_msl,
		struct rte_memseg_list *local_msl, struct hugepage_info *hi,
		unsigned int msl_idx)
{
	int ret, dir_fd;

	/* do not allow any page allocations during the time we're allocating,
	 * because file creation and locking operations are not atomic,
	 * and we might be the first or the last ones to use a particular page,
	 * so we need to ensure atomicity of every operation.
	 */
	dir_fd = open(hi->hugedir, O_RDONLY);
	if (dir_fd < 0) {
		RTE_LOG(ERR, EAL, "%s(): Cannot open '%s': %s\n", __func__,
			hi->hugedir, strerror(errno));
		return -1;
	}
	/* blocking writelock */
	if (flock(dir_fd, LOCK_EX)) {
		RTE_LOG(ERR, EAL, "%s(): Cannot lock '%s': %s\n", __func__,
			hi->hugedir, strerror(errno));
		close(dir_fd);
		return -1;
	}

	/* ensure all allocated space is the same in both lists */
	ret = sync_status(primary_msl, local_msl, hi, msl_idx, true);
	if (ret < 0)
		goto fail;

	/* ensure all unallocated space is the same in both lists */
	ret = sync_status(primary_msl, local_msl, hi, msl_idx, false);
	if (ret < 0)
		goto fail;

	/* update version number */
	local_msl->version = primary_msl->version;

	close(dir_fd);

	return 0;
fail:
	close(dir_fd);
	return -1;
}

static int
sync_walk(const struct rte_memseg_list *msl, void *arg __rte_unused)