From fad12ac8c8c2591c7f4e61d19b6a9d76cd49fafa Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Thu, 26 Jan 2012 00:09:14 +0100 Subject: CPU: Introduce ARCH_HAS_CPU_AUTOPROBE and X86 parts This patch is based on Andi Kleen's work: Implement autoprobing/loading of modules serving CPU specific features (x86cpu autoloading). And Kay Siever's work to get rid of sysdev cpu structures and making use of struct device instead. Before, the cpuid driver had to be loaded to get the x86cpu autoloading feature. With this patch autoloading works through the /sys/devices/system/cpu object Cc: Kay Sievers Cc: Dave Jones Cc: Jens Axboe Cc: Herbert Xu Cc: Huang Ying Cc: Len Brown Acked-by: Andi Kleen Signed-off-by: Thomas Renninger Acked-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- drivers/base/cpu.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'drivers/base/cpu.c') diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index db87e78d7459..2a0c670c281d 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include "base.h" @@ -223,6 +224,9 @@ int __cpuinit register_cpu(struct cpu *cpu, int num) cpu->node_id = cpu_to_node(num); cpu->dev.id = num; cpu->dev.bus = &cpu_subsys; +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE + cpu->dev.bus->uevent = arch_cpu_uevent; +#endif error = device_register(&cpu->dev); if (!error && cpu->hotpluggable) register_cpu_control(cpu); @@ -247,6 +251,10 @@ struct device *get_cpu_device(unsigned cpu) } EXPORT_SYMBOL_GPL(get_cpu_device); +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE +static DEVICE_ATTR(modalias, 0444, arch_print_cpu_modalias, NULL); +#endif + static struct attribute *cpu_root_attrs[] = { #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE &dev_attr_probe.attr, @@ -257,6 +265,9 @@ static struct attribute *cpu_root_attrs[] = { &cpu_attrs[2].attr.attr, &dev_attr_kernel_max.attr, &dev_attr_offline.attr, +#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE + &dev_attr_modalias.attr, +#endif NULL }; -- cgit v1.2.3 From 2885e25c422fb68208f677f944a45fce8eda2a3c Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 2 Feb 2012 10:36:33 -0800 Subject: driver core: cpu: remove kernel warning when removing a cpu With the movement of the cpu sysdev code to be real stuct devices, now when we remove a cpu from the system, the driver core rightfully complains that there is not a release method for this device. For now, paper over this issue by quieting the driver core, but comment this in detail. This will be resolved in future kernels to be solved properly. Reported-by: Konrad Rzeszutek Wilk Tested-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- drivers/base/cpu.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'drivers/base/cpu.c') diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index db87e78d7459..23f2c4cd48d1 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -208,6 +208,25 @@ static ssize_t print_cpus_offline(struct device *dev, } static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL); +static void cpu_device_release(struct device *dev) +{ + /* + * This is an empty function to prevent the driver core from spitting a + * warning at us. Yes, I know this is directly opposite of what the + * documentation for the driver core and kobjects say, and the author + * of this code has already been publically ridiculed for doing + * something as foolish as this. However, at this point in time, it is + * the only way to handle the issue of statically allocated cpu + * devices. The different architectures will have their cpu device + * code reworked to properly handle this in the near future, so this + * function will then be changed to correctly free up the memory held + * by the cpu device. + * + * Never copy this way of doing things, or you too will be made fun of + * on the linux-kerenl list, you have been warned. + */ +} + /* * register_cpu - Setup a sysfs device for a CPU. * @cpu - cpu->hotpluggable field set to 1 will generate a control file in @@ -223,6 +242,7 @@ int __cpuinit register_cpu(struct cpu *cpu, int num) cpu->node_id = cpu_to_node(num); cpu->dev.id = num; cpu->dev.bus = &cpu_subsys; + cpu->dev.release = cpu_device_release; error = device_register(&cpu->dev); if (!error && cpu->hotpluggable) register_cpu_control(cpu); -- cgit v1.2.3 From 29bb5d4fd3140a7d5d02d858118c74a45f15c296 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 8 Feb 2012 15:11:17 -0800 Subject: driver-core: cpu: fix kobject warning when hotplugging a cpu Due to the sysdev conversion to struct device, the cpu objects get reused when adding a cpu after offlining it, which causes a big warning that the kobject portion is not properly initialized. So clear out the object before we register it again, so all is quiet. Reported-by: Konrad Rzeszutek Wilk Tested-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- drivers/base/cpu.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/base/cpu.c') diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 23f2c4cd48d1..4dabf5077c48 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -240,6 +240,7 @@ int __cpuinit register_cpu(struct cpu *cpu, int num) int error; cpu->node_id = cpu_to_node(num); + memset(&cpu->dev, 0x00, sizeof(struct device)); cpu->dev.id = num; cpu->dev.bus = &cpu_subsys; cpu->dev.release = cpu_device_release; -- cgit v1.2.3