xref: /dpdk/examples/vm_power_manager/power_manager.c (revision d0a6a32687cf12bc97ae26b6a3d2ce14e44aa2a5)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <stdint.h>
37 #include <inttypes.h>
38 #include <sys/un.h>
39 #include <fcntl.h>
40 #include <unistd.h>
41 #include <dirent.h>
42 #include <errno.h>
43 
44 #include <sys/types.h>
45 
46 #include <rte_log.h>
47 #include <rte_power.h>
48 #include <rte_spinlock.h>
49 
50 #include "power_manager.h"
51 
52 #define RTE_LOGTYPE_POWER_MANAGER RTE_LOGTYPE_USER1
53 
54 #define POWER_SCALE_CORE(DIRECTION, core_num , ret) do { \
55 	if (core_num >= POWER_MGR_MAX_CPUS) \
56 		return -1; \
57 	if (!(global_enabled_cpus & (1ULL << core_num))) \
58 		return -1; \
59 	rte_spinlock_lock(&global_core_freq_info[core_num].power_sl); \
60 	ret = rte_power_freq_##DIRECTION(core_num); \
61 	rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl); \
62 } while (0)
63 
64 #define POWER_SCALE_MASK(DIRECTION, core_mask, ret) do { \
65 	int i; \
66 	for (i = 0; core_mask; core_mask &= ~(1 << i++)) { \
67 		if ((core_mask >> i) & 1) { \
68 			if (!(global_enabled_cpus & (1ULL << i))) \
69 				continue; \
70 			rte_spinlock_lock(&global_core_freq_info[i].power_sl); \
71 			if (rte_power_freq_##DIRECTION(i) != 1) \
72 				ret = -1; \
73 			rte_spinlock_unlock(&global_core_freq_info[i].power_sl); \
74 		} \
75 	} \
76 } while (0)
77 
78 struct freq_info {
79 	rte_spinlock_t power_sl;
80 	uint32_t freqs[RTE_MAX_LCORE_FREQS];
81 	unsigned num_freqs;
82 } __rte_cache_aligned;
83 
84 static struct freq_info global_core_freq_info[POWER_MGR_MAX_CPUS];
85 
86 static uint64_t global_enabled_cpus;
87 
88 #define SYSFS_CPU_PATH "/sys/devices/system/cpu/cpu%u/topology/core_id"
89 
90 static unsigned
91 set_host_cpus_mask(void)
92 {
93 	char path[PATH_MAX];
94 	unsigned i;
95 	unsigned num_cpus = 0;
96 
97 	for (i = 0; i < POWER_MGR_MAX_CPUS; i++) {
98 		snprintf(path, sizeof(path), SYSFS_CPU_PATH, i);
99 		if (access(path, F_OK) == 0) {
100 			global_enabled_cpus |= 1ULL << i;
101 			num_cpus++;
102 		} else
103 			return num_cpus;
104 	}
105 	return num_cpus;
106 }
107 
108 int
109 power_manager_init(void)
110 {
111 	unsigned i, num_cpus;
112 	uint64_t cpu_mask;
113 	int ret = 0;
114 
115 	num_cpus = set_host_cpus_mask();
116 	if (num_cpus == 0) {
117 		RTE_LOG(ERR, POWER_MANAGER, "Unable to detected host CPUs, please "
118 			"ensure that sufficient privileges exist to inspect sysfs\n");
119 		return -1;
120 	}
121 	rte_power_set_env(PM_ENV_ACPI_CPUFREQ);
122 	cpu_mask = global_enabled_cpus;
123 	for (i = 0; cpu_mask; cpu_mask &= ~(1 << i++)) {
124 		if (rte_power_init(i) < 0 || rte_power_freqs(i,
125 				global_core_freq_info[i].freqs,
126 				RTE_MAX_LCORE_FREQS) == 0) {
127 			RTE_LOG(ERR, POWER_MANAGER, "Unable to initialize power manager "
128 					"for core %u\n", i);
129 			global_enabled_cpus &= ~(1 << i);
130 			num_cpus--;
131 			ret = -1;
132 		}
133 		rte_spinlock_init(&global_core_freq_info[i].power_sl);
134 	}
135 	RTE_LOG(INFO, POWER_MANAGER, "Detected %u host CPUs , enabled core mask:"
136 					" 0x%"PRIx64"\n", num_cpus, global_enabled_cpus);
137 	return ret;
138 
139 }
140 
141 uint32_t
142 power_manager_get_current_frequency(unsigned core_num)
143 {
144 	uint32_t freq, index;
145 
146 	if (core_num >= POWER_MGR_MAX_CPUS) {
147 		RTE_LOG(ERR, POWER_MANAGER, "Core(%u) is out of range 0...%d\n",
148 				core_num, POWER_MGR_MAX_CPUS-1);
149 		return -1;
150 	}
151 	if (!(global_enabled_cpus & (1ULL << core_num)))
152 		return 0;
153 
154 	rte_spinlock_lock(&global_core_freq_info[core_num].power_sl);
155 	index = rte_power_get_freq(core_num);
156 	rte_spinlock_unlock(&global_core_freq_info[core_num].power_sl);
157 	if (index >= POWER_MGR_MAX_CPUS)
158 		freq = 0;
159 	else
160 		freq = global_core_freq_info[core_num].freqs[index];
161 
162 	return freq;
163 }
164 
165 int
166 power_manager_exit(void)
167 {
168 	unsigned int i;
169 	int ret = 0;
170 
171 	for (i = 0; global_enabled_cpus; global_enabled_cpus &= ~(1 << i++)) {
172 		if (rte_power_exit(i) < 0) {
173 			RTE_LOG(ERR, POWER_MANAGER, "Unable to shutdown power manager "
174 					"for core %u\n", i);
175 			ret = -1;
176 		}
177 	}
178 	global_enabled_cpus = 0;
179 	return ret;
180 }
181 
182 int
183 power_manager_scale_mask_up(uint64_t core_mask)
184 {
185 	int ret = 0;
186 
187 	POWER_SCALE_MASK(up, core_mask, ret);
188 	return ret;
189 }
190 
191 int
192 power_manager_scale_mask_down(uint64_t core_mask)
193 {
194 	int ret = 0;
195 
196 	POWER_SCALE_MASK(down, core_mask, ret);
197 	return ret;
198 }
199 
200 int
201 power_manager_scale_mask_min(uint64_t core_mask)
202 {
203 	int ret = 0;
204 
205 	POWER_SCALE_MASK(min, core_mask, ret);
206 	return ret;
207 }
208 
209 int
210 power_manager_scale_mask_max(uint64_t core_mask)
211 {
212 	int ret = 0;
213 
214 	POWER_SCALE_MASK(max, core_mask, ret);
215 	return ret;
216 }
217 
218 int
219 power_manager_scale_core_up(unsigned core_num)
220 {
221 	int ret = 0;
222 
223 	POWER_SCALE_CORE(up, core_num, ret);
224 	return ret;
225 }
226 
227 int
228 power_manager_scale_core_down(unsigned core_num)
229 {
230 	int ret = 0;
231 
232 	POWER_SCALE_CORE(down, core_num, ret);
233 	return ret;
234 }
235 
236 int
237 power_manager_scale_core_min(unsigned core_num)
238 {
239 	int ret = 0;
240 
241 	POWER_SCALE_CORE(min, core_num, ret);
242 	return ret;
243 }
244 
245 int
246 power_manager_scale_core_max(unsigned core_num)
247 {
248 	int ret = 0;
249 
250 	POWER_SCALE_CORE(max, core_num, ret);
251 	return ret;
252 }
253