diff options
Diffstat (limited to 'drivers/base/topology.c')
| -rw-r--r-- | drivers/base/topology.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/base/topology.c b/drivers/base/topology.c new file mode 100644 index 000000000000..915810f6237e --- /dev/null +++ b/drivers/base/topology.c @@ -0,0 +1,148 @@ +/* + * driver/base/topology.c - Populate sysfs with cpu topology information + * + * Written by: Zhang Yanmin, Intel Corporation + * + * Copyright (C) 2006, Intel Corp. + * + * All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ +#include <linux/sysdev.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/cpu.h> +#include <linux/module.h> +#include <linux/topology.h> + +#define define_one_ro(_name) \ +static SYSDEV_ATTR(_name, 0444, show_##_name, NULL) + +#define define_id_show_func(name) \ +static ssize_t show_##name(struct sys_device *dev, char *buf) \ +{ \ + unsigned int cpu = dev->id; \ + return sprintf(buf, "%d\n", topology_##name(cpu)); \ +} + +#define define_siblings_show_func(name) \ +static ssize_t show_##name(struct sys_device *dev, char *buf) \ +{ \ + ssize_t len = -1; \ + unsigned int cpu = dev->id; \ + len = cpumask_scnprintf(buf, NR_CPUS+1, topology_##name(cpu)); \ + return (len + sprintf(buf + len, "\n")); \ +} + +#ifdef topology_physical_package_id +define_id_show_func(physical_package_id); +define_one_ro(physical_package_id); +#define ref_physical_package_id_attr &attr_physical_package_id.attr, +#else +#define ref_physical_package_id_attr +#endif + +#ifdef topology_core_id +define_id_show_func(core_id); +define_one_ro(core_id); +#define ref_core_id_attr &attr_core_id.attr, +#else +#define ref_core_id_attr +#endif + +#ifdef topology_thread_siblings +define_siblings_show_func(thread_siblings); +define_one_ro(thread_siblings); +#define ref_thread_siblings_attr &attr_thread_siblings.attr, +#else +#define ref_thread_siblings_attr +#endif + +#ifdef topology_core_siblings +define_siblings_show_func(core_siblings); +define_one_ro(core_siblings); +#define ref_core_siblings_attr &attr_core_siblings.attr, +#else +#define ref_core_siblings_attr +#endif + +static struct attribute *default_attrs[] = { + ref_physical_package_id_attr + ref_core_id_attr + ref_thread_siblings_attr + ref_core_siblings_attr + NULL +}; + +static struct attribute_group topology_attr_group = { + .attrs = default_attrs, + .name = "topology" +}; + +/* Add/Remove cpu_topology interface for CPU device */ +static int __cpuinit topology_add_dev(struct sys_device * sys_dev) +{ + sysfs_create_group(&sys_dev->kobj, &topology_attr_group); + return 0; +} + +static int __cpuinit topology_remove_dev(struct sys_device * sys_dev) +{ + sysfs_remove_group(&sys_dev->kobj, &topology_attr_group); + return 0; +} + +static int __cpuinit topology_cpu_callback(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + unsigned int cpu = (unsigned long)hcpu; + struct sys_device *sys_dev; + + sys_dev = get_cpu_sysdev(cpu); + switch (action) { + case CPU_ONLINE: + topology_add_dev(sys_dev); + break; + case CPU_DEAD: + topology_remove_dev(sys_dev); + break; + } + return NOTIFY_OK; +} + +static struct notifier_block topology_cpu_notifier = +{ + .notifier_call = topology_cpu_callback, +}; + +static int __cpuinit topology_sysfs_init(void) +{ + int i; + + for_each_online_cpu(i) { + topology_cpu_callback(&topology_cpu_notifier, CPU_ONLINE, + (void *)(long)i); + } + + register_cpu_notifier(&topology_cpu_notifier); + + return 0; +} + +device_initcall(topology_sysfs_init); + |