From 06a4bcae1ff2cd5f6f42bd74add85ec785a26343 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 8 Nov 2006 19:46:09 -0800 Subject: [PATCH] cpu topology: consider sysfs_create_group return value Take return value of sysfs_create_group() into account. That function got called in case of CPU_ONLINE notification. Since callbacks are not allowed to fail on CPU_ONLINE notification do the sysfs group creation on CPU_UP_PREPARE notification. Also remember if creation succeeded in a bitmask. So it's possible to know whether it's legal to call sysfs_remove_group or not. In addition some other minor stuff: - since CPU_UP_PREPARE might fail add CPU_UP_CANCELED handling as well. - use hotcpu_notifier instead of register_hotcpu_notifier. - #ifdef code that isn't needed in the !CONFIG_HOTPLUG_CPU case. Signed-off-by: Heiko Carstens Acked-by: Cornelia Huck Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/base/topology.c | 55 ++++++++++++++++++++++++----------------- 1 file changed, 32 insertions(+), 23 deletions(-) diff --git a/drivers/base/topology.c b/drivers/base/topology.c index 28dccb730af..3d12b85b096 100644 --- a/drivers/base/topology.c +++ b/drivers/base/topology.c @@ -94,54 +94,63 @@ static struct attribute_group topology_attr_group = { .name = "topology" }; +static cpumask_t topology_dev_map = CPU_MASK_NONE; + /* Add/Remove cpu_topology interface for CPU device */ -static int __cpuinit topology_add_dev(struct sys_device * sys_dev) +static int __cpuinit topology_add_dev(unsigned int cpu) { - return sysfs_create_group(&sys_dev->kobj, &topology_attr_group); + int rc; + struct sys_device *sys_dev = get_cpu_sysdev(cpu); + + rc = sysfs_create_group(&sys_dev->kobj, &topology_attr_group); + if (!rc) + cpu_set(cpu, topology_dev_map); + return rc; } -static int __cpuinit topology_remove_dev(struct sys_device * sys_dev) +#ifdef CONFIG_HOTPLUG_CPU +static void __cpuinit topology_remove_dev(unsigned int cpu) { + struct sys_device *sys_dev = get_cpu_sysdev(cpu); + + if (!cpu_isset(cpu, topology_dev_map)) + return; + cpu_clear(cpu, topology_dev_map); 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 long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; - struct sys_device *sys_dev; + int rc = 0; - sys_dev = get_cpu_sysdev(cpu); switch (action) { - case CPU_ONLINE: - topology_add_dev(sys_dev); + case CPU_UP_PREPARE: + rc = topology_add_dev(cpu); break; + case CPU_UP_CANCELED: case CPU_DEAD: - topology_remove_dev(sys_dev); + topology_remove_dev(cpu); break; } - return NOTIFY_OK; + return rc ? NOTIFY_BAD : NOTIFY_OK; } - -static struct notifier_block __cpuinitdata topology_cpu_notifier = -{ - .notifier_call = topology_cpu_callback, -}; +#endif static int __cpuinit topology_sysfs_init(void) { - int i; + int cpu; + int rc; - for_each_online_cpu(i) { - topology_cpu_callback(&topology_cpu_notifier, CPU_ONLINE, - (void *)(long)i); + for_each_online_cpu(cpu) { + rc = topology_add_dev(cpu); + if (rc) + return rc; } - - register_hotcpu_notifier(&topology_cpu_notifier); + hotcpu_notifier(topology_cpu_callback, 0); return 0; } device_initcall(topology_sysfs_init); - -- 2.20.1