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-rw-r--r--drivers/base/topology.c148
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);
+