在 2013-06-10一的 12:51 +0900，Yasuaki Ishimatsu写道： > 2013/06/10 9:36, li guang wrote: > > Hi, Rafael > > > > 在 2013-06-06四的 13:00 +0200，Rafael J. Wysocki写道： > >> On Thursday, June 06, 2013 09:40:32 AM liguang wrote: > >>> This patch-set try to support physically hot-plug/unplug > >>> a cpu automatically, that is: > >>> if you offline a cpu, it will automatically actually remove > >>> a cpu, and if you hot-plug a cpu, then it will online this > >>> cpu automatically. > >> > >> No and no. > > > > Hmm... are you saying cpu online/offline designed to distinguish > > with real cpu plug/unplug? > > but, what the actual usage of online/offline? > > forgive my foolish. > > > >> > >> Why do you need this? > >> > > > > e.g. for QEMU case, if hot-plug a cpu, > > > we have to online a cpu manually if there's > > no user space support like udev to do it automatically. > > I could not understand why you do not use udev. > Please explain in detail. I did not say I can't use udev now, just for in case someone can't. > > > and also, I think maybe online/offline should be naturally > > integrated with real plug/unplug process of CPU. > > I could not understand this explanation too. > Why do we need it? > actually, I am asking if CPU online/offline have real purpose, you offline a CPU, then threads can't run on it, you online a CPU, then threads can run on it, so, the purpose here is just bouncing threads? obviously not, any profound historical reasons? I boldly think maybe online/offline should be integrated into real plug/unplug process of CPU. Thanks! > > > >> > >> > >>> so, offline is just like eject, but eject attribute seems not > >>> available since recent kernel(can't figure out when), with > >>> this driver, if allowed, it will trigger a eject cpu process. > >>> and for automatically online, it was said there are objections, > >>> don't know the reason, so, send this patch-set boldly. > >>> > >>> of course, this approach is for QEMU 's hotplug cpu emulation > >>> only, but not limited, if someone like to explore ec space to > >>> implment cpu hot-plug/unplug for real platform please > >>> feel free to continue. > >>> > >>> Li Guang (3) > >>> drivers/platform/x86: add cpu physically hotplug driver > >>> ec: add ec space notifier > >>> cpu_physic_hotplug: register handler for ec space notifier > >>> > >>> drivers/acpi/ec.c | 32 ++++++++++++++++++++++++++++++++ > >>> drivers/platform/x86/Kconfig | 8 ++++ > >>> drivers/platform/x86/Makefile | 1 + > >>> drivers/platform/x86/cpu_physic_hotplug.c | 90 +++++++++++++++++++++++++++++ > >>> include/linux/acpi.h | 2 ++ > >>> 5 files changed, 130 insertions(+), 3 deletions(-) > >>> create mode 100644 drivers/platform/x86/cpu_physic_hotplug.c > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ > > > > -- 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
