From f3c6ea1b06c71b43f751b36bd99345369fe911af Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 23 Mar 2011 22:15:54 +0100 Subject: x86: Use syscore_ops instead of sysdev classes and sysdevs Some subsystems in the x86 tree need to carry out suspend/resume and shutdown operations with one CPU on-line and interrupts disabled and they define sysdev classes and sysdevs or sysdev drivers for this purpose. This leads to unnecessarily complicated code and excessive memory usage, so switch them to using struct syscore_ops objects for this purpose instead. Generally, there are three categories of subsystems that use sysdevs for implementing PM operations: (1) subsystems whose suspend/resume callbacks ignore their arguments entirely (the majority), (2) subsystems whose suspend/resume callbacks use their struct sys_device argument, but don't really need to do that, because they can be implemented differently in an arguably simpler way (io_apic.c), and (3) subsystems whose suspend/resume callbacks use their struct sys_device argument, but the value of that argument is always the same and could be ignored (microcode_core.c). In all of these cases the subsystems in question may be readily converted to using struct syscore_ops objects for power management and shutdown. Signed-off-by: Rafael J. Wysocki Reviewed-by: Thomas Gleixner Acked-by: Ingo Molnar --- arch/x86/kernel/microcode_core.c | 34 ++++++++++++++-------------------- 1 file changed, 14 insertions(+), 20 deletions(-) (limited to 'arch/x86/kernel/microcode_core.c') diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c index 87af68e0e1e..5ed0ab549eb 100644 --- a/arch/x86/kernel/microcode_core.c +++ b/arch/x86/kernel/microcode_core.c @@ -82,6 +82,7 @@ #include #include #include +#include #include #include @@ -438,33 +439,25 @@ static int mc_sysdev_remove(struct sys_device *sys_dev) return 0; } -static int mc_sysdev_resume(struct sys_device *dev) +static struct sysdev_driver mc_sysdev_driver = { + .add = mc_sysdev_add, + .remove = mc_sysdev_remove, +}; + +/** + * mc_bp_resume - Update boot CPU microcode during resume. + */ +static void mc_bp_resume(void) { - int cpu = dev->id; + int cpu = smp_processor_id(); struct ucode_cpu_info *uci = ucode_cpu_info + cpu; - if (!cpu_online(cpu)) - return 0; - - /* - * All non-bootup cpus are still disabled, - * so only CPU 0 will apply ucode here. - * - * Moreover, there can be no concurrent - * updates from any other places at this point. - */ - WARN_ON(cpu != 0); - if (uci->valid && uci->mc) microcode_ops->apply_microcode(cpu); - - return 0; } -static struct sysdev_driver mc_sysdev_driver = { - .add = mc_sysdev_add, - .remove = mc_sysdev_remove, - .resume = mc_sysdev_resume, +static struct syscore_ops mc_syscore_ops = { + .resume = mc_bp_resume, }; static __cpuinit int @@ -542,6 +535,7 @@ static int __init microcode_init(void) if (error) return error; + register_syscore_ops(&mc_syscore_ops); register_hotcpu_notifier(&mc_cpu_notifier); pr_info("Microcode Update Driver: v" MICROCODE_VERSION -- cgit v1.2.3-70-g09d2 From 4ac5fc6a3e4d90120f292526bcaa5ee182a7411b Mon Sep 17 00:00:00 2001 From: Xiaotian Feng Date: Tue, 29 Mar 2011 16:34:32 +0800 Subject: x86, microcode: Unregister syscore_ops after microcode unloaded Currently, microcode doesn't unregister syscore_ops after it's unloaded. So if we modprobe then rmmod microcode, the stale microcode syscore_ops info will stay on syscore_ops_list. Later when we're trying to reboot/halt/shutdown the machine, kernel will panic on syscore_shutdown(). With the patch applied, I can reboot/halt/shutdown my machine successfully. Signed-off-by: Xiaotian Feng Cc: Tigran Aivazian Cc: Rafael J. Wysocki LKML-Reference: <1301387672-23661-1-git-send-email-dfeng@redhat.com> Signed-off-by: Ingo Molnar --- arch/x86/kernel/microcode_core.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/kernel/microcode_core.c') diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c index 5ed0ab549eb..f9242800bc8 100644 --- a/arch/x86/kernel/microcode_core.c +++ b/arch/x86/kernel/microcode_core.c @@ -550,6 +550,7 @@ static void __exit microcode_exit(void) microcode_dev_exit(); unregister_hotcpu_notifier(&mc_cpu_notifier); + unregister_syscore_ops(&mc_syscore_ops); get_online_cpus(); mutex_lock(µcode_mutex); -- cgit v1.2.3-70-g09d2