Hello, Tang. On Mon, Jul 29, 2013 at 10:12:40AM +0800, Tang Chen wrote: > So the point is, how to mark the hotpluggable regions and at the > same time, make > ACPI and memblock parts independent, right ? No, not at all. My point is that the roles need to be divided clearly. The firmware (be that ACPI or whatever) knows memory areas are hotpluggable but it shouldn't be making policy decisions like not dispending hotpluggable memory through memblock allocator because that part of logic has *nothing* to do with ACPI. That is the generic kernel memory management policy which will apply regardless of what type of firmware the machine happens to be running on top of. So, please make ACPI inform memblock of the hotpluggable regions and implement the allocation policies inside memblock proper. > So are you saying mark the hotpluggable regions in memblock.memory, but not > reserve them in memblock.reserved, and make the default allocate > function avoid > the hotpluggable regions in memblock.memory ? > > This way will be convenient when we put the node_data on local node > (don't need > to free regions from memblock.reserved, as you mentioned before), right? I don't care too much about the specifics and it's likely that you'll find out which way (flag in memblock.memory, separate region array or whatever) is better as implementation progresses, but let's please put things where they belong; otherwise, we end up with weird mess, and, later on, have to do things like freeing part of reserved hotpluggable memory for node data from firmware side as you said above, which basically moves part of memory allocation logic into ACPI, which is just horrible. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>