> > I doubt either Greg or Dave suggested adding duplicate interfaces for the > same functionality. > > The difference is that we needed to add the add_node interface in a new > mem_hotplug debugfs directory because it's only useful for debugging > kernel code and, thus, doesn't really have an appropriate place in sysfs. > Nobody is going to use add_node unless they lack hotpluggable memory > sections in their SRAT and want to debug the memory hotplug callers. For > example, I already wrote all of this node hotplug emulation stuff when I > wrote the node hotplug support for SLAB. > > Memory hotplug, however, does serve a non-debugging function and is > appropriate in sysfs since this is how people hotplug memory. It's an ABI > that we can't simply remove without deprecation over a substantial period > of time and in this case it doesn't seem to have a clear advantage. We > need not add special emulation support for something that is already > possible for real systems, so adding a duplicate interface in debugfs is > inappropriate. so we should still keep the sysfs memory/probe interface without any modifications, but for the debugfs mem_hotplug/probe interface, we can add the memory region to a desired node. It is an extention for the sysfs memory/probe interface, it can be used for memory hotplug emulation. Do I understand it correctly? -- Thanks & Regards, Shaohui -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>