Commit f2d2946e authored by Changwoo Min's avatar Changwoo Min Committed by Rafael J. Wysocki
Browse files

PM: EM: Implement em_nl_get_pd_table_doit() 



When a userspace requests EM_CMD_GET_PD_TABLE with an ID of a performance
domain, the kernel reports back the energy model table of the specified
performance domain. The message format of the response is as follows:

EM_A_PD_TABLE_PD_ID (NLA_U32)
EM_A_PD_TABLE_PS (NLA_NESTED)*
    EM_A_PS_PERFORMANCE (NLA_U64)
    EM_A_PS_FREQUENCY (NLA_U64)
    EM_A_PS_POWER (NLA_U64)
    EM_A_PS_COST (NLA_U64)
    EM_A_PS_FLAGS (NLA_U64)

where EM_A_PD_TABLE_PS can be repeated as many times as there are
performance states (struct em_perf_state).

Signed-off-by: default avatarChangwoo Min <changwoo@igalia.com>
Reviewed-by: default avatarLukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/20251020220914.320832-8-changwoo@igalia.com


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent d8eef045

kernel/power/em_netlink.c

+107 −1
Original line number Diff line number Diff line
@@ -102,9 +102,115 @@ int em_nl_get_pds_doit(struct sk_buff *skb, struct genl_info *info) 
	return ret;

}



static struct em_perf_domain *__em_nl_get_pd_table_id(struct nlattr **attrs)

{

	struct em_perf_domain *pd;

	int id;



	if (!attrs[EM_A_PD_TABLE_PD_ID])

		return NULL;



	id = nla_get_u32(attrs[EM_A_PD_TABLE_PD_ID]);

	pd = em_perf_domain_get_by_id(id);

	return pd;

}



static int __em_nl_get_pd_table_size(const struct em_perf_domain *pd)

{

	int id_sz, ps_sz;



	id_sz = nla_total_size(sizeof(u32));		/* EM_A_PD_TABLE_PD_ID */

	ps_sz = nla_total_size(0) +			/* EM_A_PD_TABLE_PS */

		nla_total_size_64bit(sizeof(u64)) +	/* EM_A_PS_PERFORMANCE */

		nla_total_size_64bit(sizeof(u64)) +	/* EM_A_PS_FREQUENCY */

		nla_total_size_64bit(sizeof(u64)) +	/* EM_A_PS_POWER */

		nla_total_size_64bit(sizeof(u64)) +	/* EM_A_PS_COST */

		nla_total_size_64bit(sizeof(u64));	/* EM_A_PS_FLAGS */

	ps_sz *= pd->nr_perf_states;



	return nlmsg_total_size(genlmsg_msg_size(id_sz + ps_sz));

}



static int __em_nl_get_pd_table(struct sk_buff *msg, const struct em_perf_domain *pd)

{

	struct em_perf_state *table, *ps;

	struct nlattr *entry;

	int i;



	if (nla_put_u32(msg, EM_A_PD_TABLE_PD_ID, pd->id))

		goto out_err;



	rcu_read_lock();

	table = em_perf_state_from_pd((struct em_perf_domain *)pd);



	for (i = 0; i < pd->nr_perf_states; i++) {

		ps = &table[i];



		entry = nla_nest_start(msg, EM_A_PD_TABLE_PS);

		if (!entry)

			goto out_unlock_ps;



		if (nla_put_u64_64bit(msg, EM_A_PS_PERFORMANCE,

				      ps->performance, EM_A_PS_PAD))

			goto out_cancel_ps_nest;

		if (nla_put_u64_64bit(msg, EM_A_PS_FREQUENCY,

				      ps->frequency, EM_A_PS_PAD))

			goto out_cancel_ps_nest;

		if (nla_put_u64_64bit(msg, EM_A_PS_POWER,

				      ps->power, EM_A_PS_PAD))

			goto out_cancel_ps_nest;

		if (nla_put_u64_64bit(msg, EM_A_PS_COST,

				      ps->cost, EM_A_PS_PAD))

			goto out_cancel_ps_nest;

		if (nla_put_u64_64bit(msg, EM_A_PS_FLAGS,

				      ps->flags, EM_A_PS_PAD))

			goto out_cancel_ps_nest;



		nla_nest_end(msg, entry);

	}

	rcu_read_unlock();

	return 0;



out_cancel_ps_nest:

	nla_nest_cancel(msg, entry);

out_unlock_ps:

	rcu_read_unlock();

out_err:

	return -EMSGSIZE;

}



int em_nl_get_pd_table_doit(struct sk_buff *skb, struct genl_info *info)

{

	return -EOPNOTSUPP;

	int cmd = info->genlhdr->cmd;

	int msg_sz, ret = -EMSGSIZE;

	struct em_perf_domain *pd;

	struct sk_buff *msg;

	void *hdr;



	pd = __em_nl_get_pd_table_id(info->attrs);

	if (!pd)

		return -EINVAL;



	msg_sz = __em_nl_get_pd_table_size(pd);



	msg = genlmsg_new(msg_sz, GFP_KERNEL);

	if (!msg)

		return -ENOMEM;



	hdr = genlmsg_put_reply(msg, info, &em_nl_family, 0, cmd);

	if (!hdr)

		goto out_free_msg;



	ret = __em_nl_get_pd_table(msg, pd);

	if (ret)

		goto out_free_msg;



	genlmsg_end(msg, hdr);

	return genlmsg_reply(msg, info);



out_free_msg:

	nlmsg_free(msg);

	return ret;

}



static int __init em_netlink_init(void)