From: "Andi Kleen" This patch will create machinecheck sysdev directories per CPU. All of the cpus still share the same ctl banks. When compiled with CONFIG_HOTPLUG_CPU, it will also bring up/down sysdev directories as cpus go up/down. I have tested the patch along with CONFIG_HOTPLUG_CPU option on in 2.6.13-rc1 kernel. Minor changes by AK: remove useless unload function Signed-off-by: Jacob Shin Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton --- arch/x86_64/kernel/mce.c | 93 +++++++++++++++++++++++++++++++++++++---------- 1 files changed, 74 insertions(+), 19 deletions(-) diff -puN arch/x86_64/kernel/mce.c~x86_64-create-per-cpu-machine-check-sysfs-directories arch/x86_64/kernel/mce.c --- devel/arch/x86_64/kernel/mce.c~x86_64-create-per-cpu-machine-check-sysfs-directories 2005-07-27 12:36:33.000000000 -0700 +++ devel-akpm/arch/x86_64/kernel/mce.c 2005-07-27 12:36:33.000000000 -0700 @@ -15,6 +15,8 @@ #include #include #include +#include +#include #include #include #include @@ -514,10 +516,7 @@ static struct sysdev_class mce_sysclass set_kset_name("machinecheck"), }; -static struct sys_device device_mce = { - .id = 0, - .cls = &mce_sysclass, -}; +static DEFINE_PER_CPU(struct sys_device, device_mce); /* Why are there no generic functions for this? */ #define ACCESSOR(name, var, start) \ @@ -542,27 +541,83 @@ ACCESSOR(bank4ctl,bank[4],mce_restart()) ACCESSOR(tolerant,tolerant,) ACCESSOR(check_interval,check_interval,mce_restart()) -static __cpuinit int mce_init_device(void) +/* Per cpu sysdev init. All of the cpus still share the same ctl bank */ +static __cpuinit int mce_create_device(unsigned int cpu) { int err; + if (!mce_available(&cpu_data[cpu])) + return -EIO; + + per_cpu(device_mce,cpu).id = cpu; + per_cpu(device_mce,cpu).cls = &mce_sysclass; + + err = sysdev_register(&per_cpu(device_mce,cpu)); + + if (!err) { + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_bank0ctl); + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_bank1ctl); + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_bank2ctl); + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_bank3ctl); + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_bank4ctl); + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_tolerant); + sysdev_create_file(&per_cpu(device_mce,cpu), &attr_check_interval); + } + return err; +} + +#ifdef CONFIG_HOTPLUG_CPU +static __cpuinit void mce_remove_device(unsigned int cpu) +{ + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_bank0ctl); + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_bank1ctl); + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_bank2ctl); + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_bank3ctl); + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_bank4ctl); + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_tolerant); + sysdev_remove_file(&per_cpu(device_mce,cpu), &attr_check_interval); + sysdev_unregister(&per_cpu(device_mce,cpu)); +} +#endif + +/* Get notified when a cpu comes on/off. Be hotplug friendly. */ +static __cpuinit int +mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) +{ + unsigned int cpu = (unsigned long)hcpu; + + switch (action) { + case CPU_ONLINE: + mce_create_device(cpu); + break; +#ifdef CONFIG_HOTPLUG_CPU + case CPU_DEAD: + mce_remove_device(cpu); + break; +#endif + } + return NOTIFY_OK; +} + +static struct notifier_block mce_cpu_notifier = { + .notifier_call = mce_cpu_callback, +}; + +static __init int mce_init_device(void) +{ + int err; + int i = 0; + if (!mce_available(&boot_cpu_data)) return -EIO; err = sysdev_class_register(&mce_sysclass); - if (!err) - err = sysdev_register(&device_mce); - if (!err) { - /* could create per CPU objects, but it is not worth it. */ - sysdev_create_file(&device_mce, &attr_bank0ctl); - sysdev_create_file(&device_mce, &attr_bank1ctl); - sysdev_create_file(&device_mce, &attr_bank2ctl); - sysdev_create_file(&device_mce, &attr_bank3ctl); - sysdev_create_file(&device_mce, &attr_bank4ctl); - sysdev_create_file(&device_mce, &attr_tolerant); - sysdev_create_file(&device_mce, &attr_check_interval); - } - + + for_each_online_cpu(i) { + mce_create_device(i); + } + + register_cpu_notifier(&mce_cpu_notifier); misc_register(&mce_log_device); return err; - } + device_initcall(mce_init_device); _