This adds the capability to DLPAR add and remove CPUs from the kernel. The
creates two new files /sys/devices/system/cpu/probe and
/sys/devices/system/cpu/release to handle the DLPAR addition and removal of
CPUs respectively.
CPU DLPAR add is accomplished by writing the drc-index of the CPU to the
probe file, and removal is done by writing the device-tree path of the cpu
to the release file.
Updated to include #ifdef CONFIG_HOTPLUG_CPU around the cpu hotplug specific
bits so that it will build without CONFIG_HOTPLUG_CPU defined.
Signed-off-by: Nathan Fontenot <nf...@austin.ibm.com>
---
Index: powerpc/arch/powerpc/platforms/pseries/dlpar.c
===================================================================
--- powerpc.orig/arch/powerpc/platforms/pseries/dlpar.c 2009-10-13
13:08:22.000000000 -0500
+++ powerpc/arch/powerpc/platforms/pseries/dlpar.c 2009-10-13
13:09:00.000000000 -0500
@@ -1,11 +1,11 @@
/*
- * dlpar.c - support for dynamic reconfiguration (including PCI
- * Hotplug and Dynamic Logical Partitioning on RPA platforms).
+ * dlpar.c - support for dynamic reconfiguration (including PCI,
+ * Memory, and CPU Hotplug and Dynamic Logical Partitioning on
+ * PAPR platforms).
*
* Copyright (C) 2009 Nathan Fontenot
* Copyright (C) 2009 IBM Corporation
*
- *
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
@@ -19,6 +19,7 @@
#include <linux/memory_hotplug.h>
#include <linux/sysdev.h>
#include <linux/sysfs.h>
+#include <linux/cpu.h>
#include <asm/prom.h>
@@ -408,6 +409,82 @@
return 0;
}
+#ifdef CONFIG_HOTPLUG_CPU
+static ssize_t cpu_probe_store(struct class *class, const char *buf,
+ size_t count)
+{
+ struct device_node *dn;
+ unsigned long drc_index;
+ char *cpu_name;
+ int rc;
+
+ rc = strict_strtoul(buf, 0, &drc_index);
+ if (rc)
+ return -EINVAL;
+
+ rc = acquire_drc(drc_index);
+ if (rc)
+ return rc;
+
+ dn = configure_connector(drc_index);
+ if (!dn) {
+ release_drc(drc_index);
+ return rc;
+ }
+
+ /* fixup dn name */
+ cpu_name = kzalloc(strlen(dn->full_name) + strlen("/cpus/") + 1,
+ GFP_KERNEL);
+ if (!cpu_name) {
+ free_cc_nodes(dn);
+ release_drc(drc_index);
+ return -ENOMEM;
+ }
+
+ sprintf(cpu_name, "/cpus/%s", dn->full_name);
+ kfree(dn->full_name);
+ dn->full_name = cpu_name;
+
+ rc = add_device_tree_nodes(dn);
+ if (rc)
+ release_drc(drc_index);
+
+ return rc ? rc : count;
+}
+
+static ssize_t cpu_release_store(struct class *class, const char *buf,
+ size_t count)
+{
+ struct device_node *dn;
+ u32 *drc_index;
+ int rc;
+
+ dn = of_find_node_by_path(buf);
+ if (!dn)
+ return -EINVAL;
+
+ drc_index = (u32 *)of_get_property(dn, "ibm,my-drc-index", NULL);
+ if (!drc_index) {
+ of_node_put(dn);
+ return -EINVAL;
+ }
+
+ rc = release_drc(*drc_index);
+ if (rc) {
+ of_node_put(dn);
+ return rc;
+ }
+
+ rc = remove_device_tree_nodes(dn);
+ if (rc)
+ acquire_drc(*drc_index);
+
+ of_node_put(dn);
+ return rc ? rc : count;
+}
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
#ifdef CONFIG_MEMORY_HOTPLUG
static struct property *clone_property(struct property *old_prop)
@@ -553,6 +630,13 @@
static struct class_attribute class_attr_mem_release =
__ATTR(release, S_IWUSR, NULL, memory_release_store);
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+#ifdef CONFIG_HOTPLUG_CPU
+static struct class_attribute class_attr_cpu_probe =
+ __ATTR(probe, S_IWUSR, NULL, cpu_probe_store);
+static struct class_attribute class_attr_cpu_release =
+ __ATTR(release, S_IWUSR, NULL, cpu_release_store);
#endif
static int pseries_dlpar_init(void)
@@ -567,6 +651,18 @@
"release file\n");
#endif
+#ifdef CONFIG_HOTPLUG_CPU
+ if (sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+ &class_attr_cpu_probe.attr))
+ printk(KERN_INFO "DLPAR: Could not create sysfs cpu "
+ "probe file\n");
+
+ if (sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+ &class_attr_cpu_release.attr))
+ printk(KERN_INFO "DLPAR: Could not create sysfs cpu "
+ "release file\n");
+#endif
+
return 0;
}
device_initcall(pseries_dlpar_init);
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
