1 // SPDX-License-Identifier: GPL-2.0-only
3  *  (C) 2004-2009  Dominik Brodowski <linux@dominikbrodowski.de>
19 	if (access(path, F_OK) == -1)  in is_valid_path()
21 	return 1;  in is_valid_path()
30 	if (fd == -1)  in cpupower_read_sysfs()
33 	numread = read(fd, buf, buflen - 1);  in cpupower_read_sysfs()
34 	if (numread < 1) {  in cpupower_read_sysfs()
51 	if (fd == -1)  in cpupower_write_sysfs()
54 	numwritten = write(fd, buf, buflen - 1);  in cpupower_write_sysfs()
55 	if (numwritten < 1) {  in cpupower_write_sysfs()
58 		return -1;  in cpupower_write_sysfs()
67  * Detect whether a CPU is online
70  *     1 -> if CPU is online
71  *     0 -> if CPU is offline
74 int cpupower_is_cpu_online(unsigned int cpu)  in cpupower_is_cpu_online()  argument
84 	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u", cpu);  in cpupower_is_cpu_online()
91 	 * -> cpuX directory exists, but not cpuX/online file  in cpupower_is_cpu_online()
93 	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/online", cpu);  in cpupower_is_cpu_online()
95 		return 1;  in cpupower_is_cpu_online()
98 	if (fd == -1)  in cpupower_is_cpu_online()
99 		return -errno;  in cpupower_is_cpu_online()
101 	numread = read(fd, linebuf, MAX_LINE_LEN - 1);  in cpupower_is_cpu_online()
102 	if (numread < 1) {  in cpupower_is_cpu_online()
104 		return -EIO;  in cpupower_is_cpu_online()
110 	if (value > 1)  in cpupower_is_cpu_online()
111 		return -EINVAL;  in cpupower_is_cpu_online()
116 /* returns -1 on failure, 0 on success */
117 static int sysfs_topology_read_file(unsigned int cpu, const char *fname, int *result)  in sysfs_topology_read_file()  argument
123 	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/topology/%s",  in sysfs_topology_read_file()
124 			 cpu, fname);  in sysfs_topology_read_file()
126 		return -1;  in sysfs_topology_read_file()
129 		return -1;  in sysfs_topology_read_file()
137 	if (top1->pkg < top2->pkg)  in __compare()
138 		return -1;  in __compare()
139 	else if (top1->pkg > top2->pkg)  in __compare()
140 		return 1;  in __compare()
141 	else if (top1->core < top2->core)  in __compare()
142 		return -1;  in __compare()
143 	else if (top1->core > top2->core)  in __compare()
144 		return 1;  in __compare()
145 	else if (top1->cpu < top2->cpu)  in __compare()
146 		return -1;  in __compare()
147 	else if (top1->cpu > top2->cpu)  in __compare()
148 		return 1;  in __compare()
157  * Array is sorted after ->pkg, ->core, then ->cpu
161 	int cpu, last_pkg, cpus = sysconf(_SC_NPROCESSORS_CONF);  in get_cpu_topology()  local
163 	cpu_top->core_info = malloc(sizeof(struct cpuid_core_info) * cpus);  in get_cpu_topology()
164 	if (cpu_top->core_info == NULL)  in get_cpu_topology()
165 		return -ENOMEM;  in get_cpu_topology()
166 	cpu_top->pkgs = cpu_top->cores = 0;  in get_cpu_topology()
167 	for (cpu = 0; cpu < cpus; cpu++) {  in get_cpu_topology()
168 		cpu_top->core_info[cpu].cpu = cpu;  in get_cpu_topology()
169 		cpu_top->core_info[cpu].is_online = cpupower_is_cpu_online(cpu);  in get_cpu_topology()
171 			cpu,  in get_cpu_topology()
173 			&(cpu_top->core_info[cpu].pkg)) < 0) {  in get_cpu_topology()
174 			cpu_top->core_info[cpu].pkg = -1;  in get_cpu_topology()
175 			cpu_top->core_info[cpu].core = -1;  in get_cpu_topology()
179 			cpu,  in get_cpu_topology()
181 			&(cpu_top->core_info[cpu].core)) < 0) {  in get_cpu_topology()
182 			cpu_top->core_info[cpu].pkg = -1;  in get_cpu_topology()
183 			cpu_top->core_info[cpu].core = -1;  in get_cpu_topology()
188 	qsort(cpu_top->core_info, cpus, sizeof(struct cpuid_core_info),  in get_cpu_topology()
194 	last_pkg = cpu_top->core_info[0].pkg;  in get_cpu_topology()
195 	for(cpu = 1; cpu < cpus; cpu++) {  in get_cpu_topology()
196 		if (cpu_top->core_info[cpu].pkg != last_pkg &&  in get_cpu_topology()
197 				cpu_top->core_info[cpu].pkg != -1) {  in get_cpu_topology()
199 			last_pkg = cpu_top->core_info[cpu].pkg;  in get_cpu_topology()
200 			cpu_top->pkgs++;  in get_cpu_topology()
203 	if (!(cpu_top->core_info[0].pkg == -1))  in get_cpu_topology()
204 		cpu_top->pkgs++;  in get_cpu_topology()
209 	for (cpu = 0; cpu_top->core_info[cpu].pkg = 0 && cpu < cpus; cpu++) {  in get_cpu_topology()
210 		if (cpu_top->core_info[cpu].core == 0)  in get_cpu_topology()
211 	cpu_top->cores++;  in get_cpu_topology()