Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / base / topology.c

diff --git a/kernel/drivers/base/topology.c b/kernel/drivers/base/topology.c
new file mode 100644 (file)
index 0000000..6491f45
--- /dev/null
+++ b/kernel/drivers/base/topology.c
@@ -0,0 +1,155 @@
+/*
+ * 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/mm.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/hardirq.h>
+#include <linux/topology.h>
+
+#define define_id_show_func(name)                              \
+static ssize_t name##_show(struct device *dev,                 \
+               struct device_attribute *attr, char *buf)       \
+{                                                              \
+       return sprintf(buf, "%d\n", topology_##name(dev->id));  \
+}
+
+#define define_siblings_show_map(name, mask)                           \
+static ssize_t name##_show(struct device *dev,                         \
+                          struct device_attribute *attr, char *buf)    \
+{                                                                      \
+       return cpumap_print_to_pagebuf(false, buf, topology_##mask(dev->id));\
+}
+
+#define define_siblings_show_list(name, mask)                          \
+static ssize_t name##_list_show(struct device *dev,                    \
+                               struct device_attribute *attr,          \
+                               char *buf)                              \
+{                                                                      \
+       return cpumap_print_to_pagebuf(true, buf, topology_##mask(dev->id));\
+}
+
+#define define_siblings_show_func(name, mask)  \
+       define_siblings_show_map(name, mask);   \
+       define_siblings_show_list(name, mask)
+
+define_id_show_func(physical_package_id);
+static DEVICE_ATTR_RO(physical_package_id);
+
+define_id_show_func(core_id);
+static DEVICE_ATTR_RO(core_id);
+
+define_siblings_show_func(thread_siblings, thread_cpumask);
+static DEVICE_ATTR_RO(thread_siblings);
+static DEVICE_ATTR_RO(thread_siblings_list);
+
+define_siblings_show_func(core_siblings, core_cpumask);
+static DEVICE_ATTR_RO(core_siblings);
+static DEVICE_ATTR_RO(core_siblings_list);
+
+#ifdef CONFIG_SCHED_BOOK
+define_id_show_func(book_id);
+static DEVICE_ATTR_RO(book_id);
+define_siblings_show_func(book_siblings, book_cpumask);
+static DEVICE_ATTR_RO(book_siblings);
+static DEVICE_ATTR_RO(book_siblings_list);
+#endif
+
+static struct attribute *default_attrs[] = {
+       &dev_attr_physical_package_id.attr,
+       &dev_attr_core_id.attr,
+       &dev_attr_thread_siblings.attr,
+       &dev_attr_thread_siblings_list.attr,
+       &dev_attr_core_siblings.attr,
+       &dev_attr_core_siblings_list.attr,
+#ifdef CONFIG_SCHED_BOOK
+       &dev_attr_book_id.attr,
+       &dev_attr_book_siblings.attr,
+       &dev_attr_book_siblings_list.attr,
+#endif
+       NULL
+};
+
+static struct attribute_group topology_attr_group = {
+       .attrs = default_attrs,
+       .name = "topology"
+};
+
+/* Add/Remove cpu_topology interface for CPU device */
+static int topology_add_dev(unsigned int cpu)
+{
+       struct device *dev = get_cpu_device(cpu);
+
+       return sysfs_create_group(&dev->kobj, &topology_attr_group);
+}
+
+static void topology_remove_dev(unsigned int cpu)
+{
+       struct device *dev = get_cpu_device(cpu);
+
+       sysfs_remove_group(&dev->kobj, &topology_attr_group);
+}
+
+static int topology_cpu_callback(struct notifier_block *nfb,
+                                unsigned long action, void *hcpu)
+{
+       unsigned int cpu = (unsigned long)hcpu;
+       int rc = 0;
+
+       switch (action) {
+       case CPU_UP_PREPARE:
+       case CPU_UP_PREPARE_FROZEN:
+               rc = topology_add_dev(cpu);
+               break;
+       case CPU_UP_CANCELED:
+       case CPU_UP_CANCELED_FROZEN:
+       case CPU_DEAD:
+       case CPU_DEAD_FROZEN:
+               topology_remove_dev(cpu);
+               break;
+       }
+       return notifier_from_errno(rc);
+}
+
+static int topology_sysfs_init(void)
+{
+       int cpu;
+       int rc = 0;
+
+       cpu_notifier_register_begin();
+
+       for_each_online_cpu(cpu) {
+               rc = topology_add_dev(cpu);
+               if (rc)
+                       goto out;
+       }
+       __hotcpu_notifier(topology_cpu_callback, 0);
+
+out:
+       cpu_notifier_register_done();
+       return rc;
+}
+
+device_initcall(topology_sysfs_init);