On Tuesday, January 17, 2012 02:26:40 PM Thomas Renninger wrote: > On Tuesday, January 17, 2012 12:06:19 PM Len Brown wrote: > > On 11/17/2011 05:36 PM, Thomas Renninger wrote: > > > > > Function split up, should have no functional change > > > > benefit? > The idea was: > Provide a basic init func which can be called in ACPI CPU hotplug > context safely before the CPU is brought up the first time and: > struct cpuinfo_x86 > (like CPU features) of the new CPU is not set up yet. > Do the idle/throttling/... init later when the physically hotplugged > CPU is onlined the first time (and therefore got fully booted > and initialized). > > While I had this working, I now have a better idea which does > not need this split: Wait, this cannot work. A cpu core must/should be online to get cpuidle initialized correctly. > When the ACPI CPU hotplug event is caught, fill up cpu_data(new_cpu) > data as much and good as possilbe, do something like: > memcpy(&cpu_data(new_cpu), &boot_cpu_data, sizeof(struct cpuinfo_x86); > and adjust: > phys_proc_id > cpu_core_id > apicid > initial_apicid > ... > Then cpuidle (and throttling,...) can be initialized without the need > of booting up the CPU first. > > Not sure whether the memcpy would succeed if the CPU is not (and never > was) online. From what I saw it should work, but I am not sure. > Tejun: Do you know that? Never mind. If I think it really could make sense, I better post an example code snippet what I'd like to achieve. Thomas -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
