From f2d2946eaa5c9277e5eb565796ea5d86b13f4854 Mon Sep 17 00:00:00 2001 From: Changwoo Min Date: Tue, 21 Oct 2025 07:09:11 +0900 Subject: [PATCH] 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: Changwoo Min Reviewed-by: Lukasz Luba Link: https://patch.msgid.link/20251020220914.320832-8-changwoo@igalia.com Signed-off-by: Rafael J. Wysocki --- kernel/power/em_netlink.c | 108 +++++++++++++++++++++++++++++++++++++- 1 file changed, 107 insertions(+), 1 deletion(-) diff --git a/kernel/power/em_netlink.c b/kernel/power/em_netlink.c index 16bdcf47f4d89..e144624f03353 100644 --- a/kernel/power/em_netlink.c +++ b/kernel/power/em_netlink.c @@ -102,9 +102,115 @@ out_free_msg: 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) -- 2.47.3