xref: /linux/kernel/power/em_netlink.c (revision b62ce2547fe8a8ba15857bb974bcad250c5420d6)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *
4  * Generic netlink for energy model.
5  *
6  * Copyright (c) 2025 Valve Corporation.
7  * Author: Changwoo Min <changwoo@igalia.com>
8  */
9 
10 #define pr_fmt(fmt) "energy_model: " fmt
11 
12 #include <linux/energy_model.h>
13 #include <net/sock.h>
14 #include <net/genetlink.h>
15 #include <uapi/linux/dev_energymodel.h>
16 
17 #include "em_netlink.h"
18 #include "em_netlink_autogen.h"
19 
20 /*************************** Command encoding ********************************/
21 struct dump_ctx {
22 	int idx;
23 	int start;
24 	struct sk_buff *skb;
25 	struct netlink_callback *cb;
26 };
27 
__em_nl_get_pd_size(struct em_perf_domain * pd,void * data)28 static int __em_nl_get_pd_size(struct em_perf_domain *pd, void *data)
29 {
30 	int nr_cpus, msg_sz, cpus_sz;
31 	int *tot_msg_sz = data;
32 
33 	nr_cpus = cpumask_weight(to_cpumask(pd->cpus));
34 	cpus_sz = nla_total_size_64bit(sizeof(u64)) * nr_cpus;
35 
36 	msg_sz = nla_total_size(0) +
37 		 /* DEV_ENERGYMODEL_A_PERF_DOMAINS_PERF_DOMAIN */
38 		 nla_total_size(sizeof(u32)) +
39 		 /* DEV_ENERGYMODEL_A_PERF_DOMAIN_PERF_DOMAIN_ID */
40 		 nla_total_size_64bit(sizeof(u64)) +
41 		 /* DEV_ENERGYMODEL_A_PERF_DOMAIN_FLAGS */
42 		 nla_total_size(cpus_sz);
43 		 /* DEV_ENERGYMODEL_A_PERF_DOMAIN_CPUS */
44 
45 	*tot_msg_sz += nlmsg_total_size(genlmsg_msg_size(msg_sz));
46 	return 0;
47 }
48 
__em_nl_get_pd(struct em_perf_domain * pd,void * data)49 static int __em_nl_get_pd(struct em_perf_domain *pd, void *data)
50 {
51 	struct sk_buff *msg = data;
52 	struct cpumask *cpumask;
53 	int cpu;
54 
55 	if (nla_put_u32(msg, DEV_ENERGYMODEL_A_PERF_DOMAIN_PERF_DOMAIN_ID,
56 			pd->id))
57 		goto out_cancel_nest;
58 
59 	if (nla_put_u64_64bit(msg, DEV_ENERGYMODEL_A_PERF_DOMAIN_FLAGS,
60 			      pd->flags, DEV_ENERGYMODEL_A_PERF_DOMAIN_PAD))
61 		goto out_cancel_nest;
62 
63 	cpumask = to_cpumask(pd->cpus);
64 	for_each_cpu(cpu, cpumask) {
65 		if (nla_put_u64_64bit(msg, DEV_ENERGYMODEL_A_PERF_DOMAIN_CPUS,
66 				      cpu, DEV_ENERGYMODEL_A_PERF_DOMAIN_PAD))
67 			goto out_cancel_nest;
68 	}
69 
70 	return 0;
71 
72 out_cancel_nest:
73 	return -EMSGSIZE;
74 }
75 
__em_nl_get_pd_for_dump(struct em_perf_domain * pd,void * data)76 static int __em_nl_get_pd_for_dump(struct em_perf_domain *pd, void *data)
77 {
78 	const struct genl_info *info;
79 	struct dump_ctx *ctx = data;
80 	void *hdr;
81 	int ret;
82 
83 	if (ctx->idx++ < ctx->start)
84 		return 0;
85 
86 	info = genl_info_dump(ctx->cb);
87 	hdr = genlmsg_iput(ctx->skb, info);
88 	if (!hdr) {
89 		genlmsg_cancel(ctx->skb, hdr);
90 		return -EMSGSIZE;
91 	}
92 
93 	ret = __em_nl_get_pd(pd, ctx->skb);
94 	genlmsg_end(ctx->skb, hdr);
95 	return ret;
96 }
97 
dev_energymodel_nl_get_perf_domains_doit(struct sk_buff * skb,struct genl_info * info)98 int dev_energymodel_nl_get_perf_domains_doit(struct sk_buff *skb,
99 					      struct genl_info *info)
100 {
101 	int id, ret = -EMSGSIZE, msg_sz = 0;
102 	int cmd = info->genlhdr->cmd;
103 	struct em_perf_domain *pd;
104 	struct sk_buff *msg;
105 	void *hdr;
106 
107 	if (!info->attrs[DEV_ENERGYMODEL_A_PERF_DOMAIN_PERF_DOMAIN_ID])
108 		return -EINVAL;
109 
110 	id = nla_get_u32(info->attrs[DEV_ENERGYMODEL_A_PERF_DOMAIN_PERF_DOMAIN_ID]);
111 	pd = em_perf_domain_get_by_id(id);
112 
113 	__em_nl_get_pd_size(pd, &msg_sz);
114 	msg = genlmsg_new(msg_sz, GFP_KERNEL);
115 	if (!msg)
116 		return -ENOMEM;
117 
118 	hdr = genlmsg_put_reply(msg, info, &dev_energymodel_nl_family, 0, cmd);
119 	if (!hdr)
120 		goto out_free_msg;
121 
122 	ret = __em_nl_get_pd(pd, msg);
123 	if (ret)
124 		goto out_cancel_msg;
125 	genlmsg_end(msg, hdr);
126 
127 	return genlmsg_reply(msg, info);
128 
129 out_cancel_msg:
130 	genlmsg_cancel(msg, hdr);
131 out_free_msg:
132 	nlmsg_free(msg);
133 	return ret;
134 }
135 
dev_energymodel_nl_get_perf_domains_dumpit(struct sk_buff * skb,struct netlink_callback * cb)136 int dev_energymodel_nl_get_perf_domains_dumpit(struct sk_buff *skb,
137 						struct netlink_callback *cb)
138 {
139 	struct dump_ctx ctx = {
140 		.idx = 0,
141 		.start = cb->args[0],
142 		.skb = skb,
143 		.cb = cb,
144 	};
145 
146 	return for_each_em_perf_domain(__em_nl_get_pd_for_dump, &ctx);
147 }
148 
__em_nl_get_pd_table_id(struct nlattr ** attrs)149 static struct em_perf_domain *__em_nl_get_pd_table_id(struct nlattr **attrs)
150 {
151 	struct em_perf_domain *pd;
152 	int id;
153 
154 	if (!attrs[DEV_ENERGYMODEL_A_PERF_TABLE_PERF_DOMAIN_ID])
155 		return NULL;
156 
157 	id = nla_get_u32(attrs[DEV_ENERGYMODEL_A_PERF_TABLE_PERF_DOMAIN_ID]);
158 	pd = em_perf_domain_get_by_id(id);
159 	return pd;
160 }
161 
__em_nl_get_pd_table_size(const struct em_perf_domain * pd)162 static int __em_nl_get_pd_table_size(const struct em_perf_domain *pd)
163 {
164 	int id_sz, ps_sz;
165 
166 	id_sz = nla_total_size(sizeof(u32));
167 		/* DEV_ENERGYMODEL_A_PERF_TABLE_PERF_DOMAIN_ID */
168 	ps_sz = nla_total_size(0) +
169 		/* DEV_ENERGYMODEL_A_PERF_TABLE_PERF_STATE */
170 		nla_total_size_64bit(sizeof(u64)) +
171 		/* DEV_ENERGYMODEL_A_PERF_STATE_PERFORMANCE */
172 		nla_total_size_64bit(sizeof(u64)) +
173 		/* DEV_ENERGYMODEL_A_PERF_STATE_FREQUENCY */
174 		nla_total_size_64bit(sizeof(u64)) +
175 		/* DEV_ENERGYMODEL_A_PERF_STATE_POWER */
176 		nla_total_size_64bit(sizeof(u64)) +
177 		/* DEV_ENERGYMODEL_A_PERF_STATE_COST */
178 		nla_total_size_64bit(sizeof(u64));
179 		/* DEV_ENERGYMODEL_A_PERF_STATE_FLAGS */
180 	ps_sz *= pd->nr_perf_states;
181 
182 	return nlmsg_total_size(genlmsg_msg_size(id_sz + ps_sz));
183 }
184 
185 static
__em_nl_get_pd_table(struct sk_buff * msg,const struct em_perf_domain * pd)186 int __em_nl_get_pd_table(struct sk_buff *msg, const struct em_perf_domain *pd)
187 {
188 	struct em_perf_state *table, *ps;
189 	struct nlattr *entry;
190 	int i;
191 
192 	if (nla_put_u32(msg, DEV_ENERGYMODEL_A_PERF_TABLE_PERF_DOMAIN_ID,
193 			pd->id))
194 		goto out_err;
195 
196 	rcu_read_lock();
197 	table = em_perf_state_from_pd((struct em_perf_domain *)pd);
198 
199 	for (i = 0; i < pd->nr_perf_states; i++) {
200 		ps = &table[i];
201 
202 		entry = nla_nest_start(msg,
203 				       DEV_ENERGYMODEL_A_PERF_TABLE_PERF_STATE);
204 		if (!entry)
205 			goto out_unlock_ps;
206 
207 		if (nla_put_u64_64bit(msg,
208 				      DEV_ENERGYMODEL_A_PERF_STATE_PERFORMANCE,
209 				      ps->performance,
210 				      DEV_ENERGYMODEL_A_PERF_STATE_PAD))
211 			goto out_cancel_ps_nest;
212 		if (nla_put_u64_64bit(msg,
213 				      DEV_ENERGYMODEL_A_PERF_STATE_FREQUENCY,
214 				      ps->frequency,
215 				      DEV_ENERGYMODEL_A_PERF_STATE_PAD))
216 			goto out_cancel_ps_nest;
217 		if (nla_put_u64_64bit(msg,
218 				      DEV_ENERGYMODEL_A_PERF_STATE_POWER,
219 				      ps->power,
220 				      DEV_ENERGYMODEL_A_PERF_STATE_PAD))
221 			goto out_cancel_ps_nest;
222 		if (nla_put_u64_64bit(msg,
223 				      DEV_ENERGYMODEL_A_PERF_STATE_COST,
224 				      ps->cost,
225 				      DEV_ENERGYMODEL_A_PERF_STATE_PAD))
226 			goto out_cancel_ps_nest;
227 		if (nla_put_u64_64bit(msg,
228 				      DEV_ENERGYMODEL_A_PERF_STATE_FLAGS,
229 				      ps->flags,
230 				      DEV_ENERGYMODEL_A_PERF_STATE_PAD))
231 			goto out_cancel_ps_nest;
232 
233 		nla_nest_end(msg, entry);
234 	}
235 	rcu_read_unlock();
236 	return 0;
237 
238 out_cancel_ps_nest:
239 	nla_nest_cancel(msg, entry);
240 out_unlock_ps:
241 	rcu_read_unlock();
242 out_err:
243 	return -EMSGSIZE;
244 }
245 
dev_energymodel_nl_get_perf_table_doit(struct sk_buff * skb,struct genl_info * info)246 int dev_energymodel_nl_get_perf_table_doit(struct sk_buff *skb,
247 					    struct genl_info *info)
248 {
249 	int cmd = info->genlhdr->cmd;
250 	int msg_sz, ret = -EMSGSIZE;
251 	struct em_perf_domain *pd;
252 	struct sk_buff *msg;
253 	void *hdr;
254 
255 	pd = __em_nl_get_pd_table_id(info->attrs);
256 	if (!pd)
257 		return -EINVAL;
258 
259 	msg_sz = __em_nl_get_pd_table_size(pd);
260 
261 	msg = genlmsg_new(msg_sz, GFP_KERNEL);
262 	if (!msg)
263 		return -ENOMEM;
264 
265 	hdr = genlmsg_put_reply(msg, info, &dev_energymodel_nl_family, 0, cmd);
266 	if (!hdr)
267 		goto out_free_msg;
268 
269 	ret = __em_nl_get_pd_table(msg, pd);
270 	if (ret)
271 		goto out_free_msg;
272 
273 	genlmsg_end(msg, hdr);
274 	return genlmsg_reply(msg, info);
275 
276 out_free_msg:
277 	nlmsg_free(msg);
278 	return ret;
279 }
280 
281 
282 /**************************** Event encoding *********************************/
__em_notify_pd_table(const struct em_perf_domain * pd,int ntf_type)283 static void __em_notify_pd_table(const struct em_perf_domain *pd, int ntf_type)
284 {
285 	struct sk_buff *msg;
286 	int msg_sz, ret = -EMSGSIZE;
287 	void *hdr;
288 
289 	if (!genl_has_listeners(&dev_energymodel_nl_family, &init_net, DEV_ENERGYMODEL_NLGRP_EVENT))
290 		return;
291 
292 	msg_sz = __em_nl_get_pd_table_size(pd);
293 
294 	msg = genlmsg_new(msg_sz, GFP_KERNEL);
295 	if (!msg)
296 		return;
297 
298 	hdr = genlmsg_put(msg, 0, 0, &dev_energymodel_nl_family, 0, ntf_type);
299 	if (!hdr)
300 		goto out_free_msg;
301 
302 	ret = __em_nl_get_pd_table(msg, pd);
303 	if (ret)
304 		goto out_free_msg;
305 
306 	genlmsg_end(msg, hdr);
307 
308 	genlmsg_multicast(&dev_energymodel_nl_family, msg, 0,
309 			  DEV_ENERGYMODEL_NLGRP_EVENT, GFP_KERNEL);
310 
311 	return;
312 
313 out_free_msg:
314 	nlmsg_free(msg);
315 }
316 
em_notify_pd_created(const struct em_perf_domain * pd)317 void em_notify_pd_created(const struct em_perf_domain *pd)
318 {
319 	__em_notify_pd_table(pd, DEV_ENERGYMODEL_CMD_PERF_DOMAIN_CREATED);
320 }
321 
em_notify_pd_updated(const struct em_perf_domain * pd)322 void em_notify_pd_updated(const struct em_perf_domain *pd)
323 {
324 	__em_notify_pd_table(pd, DEV_ENERGYMODEL_CMD_PERF_DOMAIN_UPDATED);
325 }
326 
__em_notify_pd_deleted_size(const struct em_perf_domain * pd)327 static int __em_notify_pd_deleted_size(const struct em_perf_domain *pd)
328 {
329 	int id_sz = nla_total_size(sizeof(u32)); /* DEV_ENERGYMODEL_A_PERF_TABLE_PERF_DOMAIN_ID */
330 
331 	return nlmsg_total_size(genlmsg_msg_size(id_sz));
332 }
333 
em_notify_pd_deleted(const struct em_perf_domain * pd)334 void em_notify_pd_deleted(const struct em_perf_domain *pd)
335 {
336 	struct sk_buff *msg;
337 	void *hdr;
338 	int msg_sz;
339 
340 	if (!genl_has_listeners(&dev_energymodel_nl_family, &init_net,
341 				DEV_ENERGYMODEL_NLGRP_EVENT))
342 		return;
343 
344 	msg_sz = __em_notify_pd_deleted_size(pd);
345 
346 	msg = genlmsg_new(msg_sz, GFP_KERNEL);
347 	if (!msg)
348 		return;
349 
350 	hdr = genlmsg_put(msg, 0, 0, &dev_energymodel_nl_family, 0,
351 			  DEV_ENERGYMODEL_CMD_PERF_DOMAIN_DELETED);
352 	if (!hdr)
353 		goto out_free_msg;
354 
355 	if (nla_put_u32(msg, DEV_ENERGYMODEL_A_PERF_TABLE_PERF_DOMAIN_ID,
356 			pd->id))
357 		goto out_free_msg;
358 
359 	genlmsg_end(msg, hdr);
360 
361 	genlmsg_multicast(&dev_energymodel_nl_family, msg, 0,
362 			  DEV_ENERGYMODEL_NLGRP_EVENT, GFP_KERNEL);
363 
364 	return;
365 
366 out_free_msg:
367 	nlmsg_free(msg);
368 }
369 
370 /**************************** Initialization *********************************/
em_netlink_init(void)371 static int __init em_netlink_init(void)
372 {
373 	return genl_register_family(&dev_energymodel_nl_family);
374 }
375 postcore_initcall(em_netlink_init);
376