Commit 61df94ce authored by Wang Wensheng's avatar Wang Wensheng
Browse files

mm/sharepool: Implement mg_sp_group_id_by_pid() 

ascend inclusion
category: Feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8LNGH



---------------------------------------------

This is used to find the group for a task.
Also add spg management code.

Signed-off-by: default avatarWang Wensheng <wangwensheng4@huawei.com>
parent aa42d23d

mm/share_pool.c

+55 −1
Original line number Diff line number Diff line
@@ -874,7 +874,61 @@ static struct sp_group *sp_group_get_from_mm(struct mm_struct *mm, int spg_id, 
 */

int mg_sp_group_id_by_pid(int tgid, int *spg_ids, int *num)

{

	int ret = 0, real_count;

	struct sp_group_node *node;

	struct sp_group_master *master = NULL;

	struct task_struct *tsk;



	if (!sp_is_enabled())

		return -EOPNOTSUPP;



	check_interrupt_context();



	if (!spg_ids || !num || *num <= 0)

		return -EINVAL;



	ret = get_task(tgid, &tsk);

	if (ret)

		return ret;



	down_read(&sp_global_sem);

	task_lock(tsk);

	if (tsk->mm)

		master = tsk->mm->sp_group_master;

	task_unlock(tsk);



	if (!master) {

		ret = -ENODEV;

		goto out_up_read;

	}



	/*

	 * There is a local group for each process which is used for

	 * passthrough allocation. The local group is a internal

	 * implementation for convenience and is not attempt to bother

	 * the user.

	 */

	real_count = master->group_num - 1;

	if (real_count <= 0) {

		ret = -ENODEV;

		goto out_up_read;

	}

	if ((unsigned int)*num < real_count) {

		ret = -E2BIG;

		goto out_up_read;

	}

	*num = real_count;



	list_for_each_entry(node, &master->group_head, group_node) {

		if (is_local_group(node->spg->id))

			continue;

		*(spg_ids++) = node->spg->id;

	}



out_up_read:

	up_read(&sp_global_sem);

	put_task_struct(tsk);

	return ret;

}

EXPORT_SYMBOL_GPL(mg_sp_group_id_by_pid);