cpu.c revision 024f78462c3da710642a54939888a92e28704653
11da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 28a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers * CPU subsystem support 31da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 41da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 5024f78462c3da710642a54939888a92e28704653Ben Hutchings#include <linux/kernel.h> 61da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/module.h> 71da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/init.h> 8f6a570333e554b48ad589e7137c77c57809eee81Al Viro#include <linux/sched.h> 91da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/cpu.h> 101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/topology.h> 111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <linux/device.h> 1276b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyuki#include <linux/node.h> 135a0e3ad6af8660be21ca98a971cd00f331318c05Tejun Heo#include <linux/gfp.h> 141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 15a1bdc7aad8b557176ccecff1da137ebe3090871eBen Dooks#include "base.h" 161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 178a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstruct bus_type cpu_subsys = { 18af5ca3f4ec5cc4432a42a73b050dd8898ce8fd00Kay Sievers .name = "cpu", 198a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers .dev_name = "cpu", 201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds}; 218a25a2fd126c621f44f3aeaef80d51f00fc11639Kay SieversEXPORT_SYMBOL_GPL(cpu_subsys); 221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 238a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEFINE_PER_CPU(struct device *, cpu_sys_devices); 24ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj 251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#ifdef CONFIG_HOTPLUG_CPU 268a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t show_online(struct device *dev, 278a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, 284a0b2b4dbe1335b8b9886ba3dc85a145d5d938edAndi Kleen char *buf) 291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 308a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct cpu *cpu = container_of(dev, struct cpu, dev); 311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 328a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers return sprintf(buf, "%u\n", !!cpu_online(cpu->dev.id)); 331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 358a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t __ref store_online(struct device *dev, 368a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, 378a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers const char *buf, size_t count) 381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 398a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct cpu *cpu = container_of(dev, struct cpu, dev); 401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ssize_t ret; 411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 4251badebdcf394cc5fd574a524b55b3f6085e5e9cGautham R Shenoy cpu_hotplug_driver_lock(); 431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds switch (buf[0]) { 441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case '0': 458a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers ret = cpu_down(cpu->dev.id); 461da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (!ret) 47312c004d36ce6c739512bac83b452f4c20ab1f62Kay Sievers kobject_uevent(&dev->kobj, KOBJ_OFFLINE); 481da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 491da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds case '1': 508a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers ret = cpu_up(cpu->dev.id); 51fb69c3907ead36b9e9f41ea6f0d0e0ae10a38a47Nathan Lynch if (!ret) 52312c004d36ce6c739512bac83b452f4c20ab1f62Kay Sievers kobject_uevent(&dev->kobj, KOBJ_ONLINE); 531da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds break; 541da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds default: 551da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ret = -EINVAL; 561da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds } 5751badebdcf394cc5fd574a524b55b3f6085e5e9cGautham R Shenoy cpu_hotplug_driver_unlock(); 581da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 591da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds if (ret >= 0) 601da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ret = count; 611da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return ret; 621da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 638a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEVICE_ATTR(online, 0644, show_online, store_online); 641da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 656c847402e1c69c1cfe2bddeadc8391bacbb3d0a5Sam Ravnborgstatic void __cpuinit register_cpu_control(struct cpu *cpu) 661da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 678a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers device_create_file(&cpu->dev, &dev_attr_online); 681da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 6976b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyukivoid unregister_cpu(struct cpu *cpu) 701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 718a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers int logical_cpu = cpu->dev.id; 721da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 7376b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyuki unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu)); 7476b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyuki 758a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers device_remove_file(&cpu->dev, &dev_attr_online); 761da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 778a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers device_unregister(&cpu->dev); 78e37d05dad7ff9744efd8ea95a70d389e9a65a6fcMike Travis per_cpu(cpu_sys_devices, logical_cpu) = NULL; 791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return; 801da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 8112633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot 8212633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE 838a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t cpu_probe_store(struct device *dev, 848a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, 8567fc233f4fb67907861b4077cea5294035f80dc7Stephen Rothwell const char *buf, 8612633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot size_t count) 8712633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot{ 8812633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot return arch_cpu_probe(buf, count); 8912633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot} 9012633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot 918a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t cpu_release_store(struct device *dev, 928a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, 9367fc233f4fb67907861b4077cea5294035f80dc7Stephen Rothwell const char *buf, 9412633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot size_t count) 9512633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot{ 9612633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot return arch_cpu_release(buf, count); 9712633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot} 9812633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot 998a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store); 1008a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store); 10112633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ 10212633e803a2a556f6469e0933d08233d0844a2d9Nathan Fontenot 1031da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#else /* ... !CONFIG_HOTPLUG_CPU */ 1041da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvaldsstatic inline void register_cpu_control(struct cpu *cpu) 1051da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 1061da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 1071da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#endif /* CONFIG_HOTPLUG_CPU */ 1081da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 10951be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal#ifdef CONFIG_KEXEC 11051be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal#include <linux/kexec.h> 11151be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal 1128a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t show_crash_notes(struct device *dev, struct device_attribute *attr, 1134a0b2b4dbe1335b8b9886ba3dc85a145d5d938edAndi Kleen char *buf) 11451be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal{ 1158a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct cpu *cpu = container_of(dev, struct cpu, dev); 11651be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal ssize_t rc; 11751be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal unsigned long long addr; 11851be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal int cpunum; 11951be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal 1208a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers cpunum = cpu->dev.id; 12151be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal 12251be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal /* 12351be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal * Might be reading other cpu's data based on which cpu read thread 12451be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal * has been scheduled. But cpu data (memory) is allocated once during 12551be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal * boot up and this data does not change there after. Hence this 12651be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal * operation should be safe. No locking required. 12751be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal */ 1283b034b0d084221596bf35c8d893e1d4d5477b9ccVivek Goyal addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum)); 12951be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal rc = sprintf(buf, "%Lx\n", addr); 13051be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal return rc; 13151be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal} 1328a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEVICE_ATTR(crash_notes, 0400, show_crash_notes, NULL); 13351be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal#endif 13451be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal 1351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 1369d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis * Print cpu online, possible, present, and system maps 1379d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis */ 138265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen 139265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleenstruct cpu_attr { 1408a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute attr; 141265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen const struct cpumask *const * const map; 142265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen}; 143265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen 1448a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t show_cpus_attr(struct device *dev, 1458a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, 146265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen char *buf) 1479d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis{ 148265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen struct cpu_attr *ca = container_of(attr, struct cpu_attr, attr); 149265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen int n = cpulist_scnprintf(buf, PAGE_SIZE-2, *(ca->map)); 1509d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis 1519d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis buf[n++] = '\n'; 1529d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis buf[n] = '\0'; 1539d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis return n; 1549d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis} 1559d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis 1568a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers#define _CPU_ATTR(name, map) \ 1578a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers { __ATTR(name, 0444, show_cpus_attr, NULL), map } 1589d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis 1598a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers/* Keep in sync with cpu_subsys_attrs */ 160265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleenstatic struct cpu_attr cpu_attrs[] = { 161265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen _CPU_ATTR(online, &cpu_online_mask), 162265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen _CPU_ATTR(possible, &cpu_possible_mask), 163265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen _CPU_ATTR(present, &cpu_present_mask), 164265d2e2e31c5f6dc1b20ae1653a17fdba706f79eAndi Kleen}; 1659d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis 166e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis/* 167e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis * Print values for NR_CPUS and offlined cpus 168e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis */ 1698a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t print_cpus_kernel_max(struct device *dev, 1708a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, char *buf) 171e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis{ 1728fd2d2d5aaf086cfa3b2e2e58cab96b7afdc9e51Mike Travis int n = snprintf(buf, PAGE_SIZE-2, "%d\n", NR_CPUS - 1); 173e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis return n; 174e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis} 1758a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEVICE_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL); 176e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 177e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis/* arch-optional setting to enable display of offline cpus >= nr_cpu_ids */ 178e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travisunsigned int total_cpus; 179e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 1808a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic ssize_t print_cpus_offline(struct device *dev, 1818a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers struct device_attribute *attr, char *buf) 182e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis{ 183e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis int n = 0, len = PAGE_SIZE-2; 184e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis cpumask_var_t offline; 185e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 186e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis /* display offline cpus < nr_cpu_ids */ 187e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis if (!alloc_cpumask_var(&offline, GFP_KERNEL)) 188e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis return -ENOMEM; 189cdc6e3d3968052cebb2f2ddcd742bff29fbd1a90Jan Beulich cpumask_andnot(offline, cpu_possible_mask, cpu_online_mask); 190e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis n = cpulist_scnprintf(buf, len, offline); 191e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis free_cpumask_var(offline); 192e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 193e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis /* display offline cpus >= nr_cpu_ids */ 194e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis if (total_cpus && nr_cpu_ids < total_cpus) { 195e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis if (n && n < len) 196e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis buf[n++] = ','; 197e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 198e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis if (nr_cpu_ids == total_cpus-1) 199e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis n += snprintf(&buf[n], len - n, "%d", nr_cpu_ids); 200e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis else 201e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis n += snprintf(&buf[n], len - n, "%d-%d", 202e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis nr_cpu_ids, total_cpus-1); 203e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis } 204e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 205e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis n += snprintf(&buf[n], len - n, "\n"); 206e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis return n; 207e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis} 2088a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL); 209e057d7aea9d8f2a46cd440d8bfb72245d4e72d79Mike Travis 2109d1fe3236a1d64ab687e16b4cbbaa1383352a2c1Mike Travis/* 211405ae7d381302468ecc803f2148a2ae40a04c999Robert P. J. Day * register_cpu - Setup a sysfs device for a CPU. 21272486f1f8f0a2bc828b9d30cf4690cf2dd6807fcSiddha, Suresh B * @cpu - cpu->hotpluggable field set to 1 will generate a control file in 21372486f1f8f0a2bc828b9d30cf4690cf2dd6807fcSiddha, Suresh B * sysfs for this CPU. 2141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * @num - CPU number to use when creating the device. 2151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 2161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Initialize and register the CPU device. 2171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 21833b5f31bbc4d047d048d8635fccdab38ffe6c287Randy Dunlapint __cpuinit register_cpu(struct cpu *cpu, int num) 2191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 2201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds int error; 22176b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyuki 2228a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers cpu->node_id = cpu_to_node(num); 2238a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers cpu->dev.id = num; 2248a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers cpu->dev.bus = &cpu_subsys; 2258a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers error = device_register(&cpu->dev); 22672486f1f8f0a2bc828b9d30cf4690cf2dd6807fcSiddha, Suresh B if (!error && cpu->hotpluggable) 2271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds register_cpu_control(cpu); 228ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj if (!error) 2298a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers per_cpu(cpu_sys_devices, num) = &cpu->dev; 23076b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyuki if (!error) 23176b67ed9dce69a6a329cdd66f94af1787f417b62KAMEZAWA Hiroyuki register_cpu_under_node(num, cpu_to_node(num)); 23251be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal 23351be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal#ifdef CONFIG_KEXEC 23451be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal if (!error) 2358a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers error = device_create_file(&cpu->dev, &dev_attr_crash_notes); 23651be5606d9ff9eb27ed6514f6172fbd7578a25d6Vivek Goyal#endif 2371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds return error; 2381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 2391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2408a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstruct device *get_cpu_device(unsigned cpu) 241ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj{ 242e37d05dad7ff9744efd8ea95a70d389e9a65a6fcMike Travis if (cpu < nr_cpu_ids && cpu_possible(cpu)) 243e37d05dad7ff9744efd8ea95a70d389e9a65a6fcMike Travis return per_cpu(cpu_sys_devices, cpu); 244ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj else 245ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj return NULL; 246ad74557a49d1dea428fb0ad60e75a5aa37610e1dAshok Raj} 2478a25a2fd126c621f44f3aeaef80d51f00fc11639Kay SieversEXPORT_SYMBOL_GPL(get_cpu_device); 2488a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers 2498a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic struct attribute *cpu_root_attrs[] = { 2508a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE 2518a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &dev_attr_probe.attr, 2528a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &dev_attr_release.attr, 2538a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers#endif 2548a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &cpu_attrs[0].attr.attr, 2558a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &cpu_attrs[1].attr.attr, 2568a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &cpu_attrs[2].attr.attr, 2578a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &dev_attr_kernel_max.attr, 2588a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &dev_attr_offline.attr, 2598a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers NULL 2608a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers}; 2618a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers 2628a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic struct attribute_group cpu_root_attr_group = { 2638a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers .attrs = cpu_root_attrs, 2648a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers}; 2658a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers 2668a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sieversstatic const struct attribute_group *cpu_root_attr_groups[] = { 2678a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers &cpu_root_attr_group, 2688a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers NULL, 2698a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers}; 2701da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 2712987557f52b97f679f0c324d8f51b8d66e1f2084Josh Triplettbool cpu_is_hotpluggable(unsigned cpu) 2722987557f52b97f679f0c324d8f51b8d66e1f2084Josh Triplett{ 2737affca3537d74365128e477b40c529d6f2fe86c8Linus Torvalds struct device *dev = get_cpu_device(cpu); 2747affca3537d74365128e477b40c529d6f2fe86c8Linus Torvalds return dev && container_of(dev, struct cpu, dev)->hotpluggable; 2752987557f52b97f679f0c324d8f51b8d66e1f2084Josh Triplett} 2762987557f52b97f679f0c324d8f51b8d66e1f2084Josh TriplettEXPORT_SYMBOL_GPL(cpu_is_hotpluggable); 2772987557f52b97f679f0c324d8f51b8d66e1f2084Josh Triplett 278024f78462c3da710642a54939888a92e28704653Ben Hutchingsvoid __init cpu_dev_init(void) 2791da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds{ 280024f78462c3da710642a54939888a92e28704653Ben Hutchings if (subsys_system_register(&cpu_subsys, cpu_root_attr_groups)) 281024f78462c3da710642a54939888a92e28704653Ben Hutchings panic("Failed to register CPU subsystem"); 2828a25a2fd126c621f44f3aeaef80d51f00fc11639Kay Sievers 2835c45bf279d378d436ce45825c0f136696c7b6109Siddha, Suresh B#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) 284024f78462c3da710642a54939888a92e28704653Ben Hutchings sched_create_sysfs_power_savings_entries(cpu_subsys.dev_root); 2855c45bf279d378d436ce45825c0f136696c7b6109Siddha, Suresh B#endif 2861da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds} 287