>> numa_node_id() is really silly. This might lead to allocate from offlining >> node. > > Right, it should've been alloc_huge_page(). > >> and, offline_pages() should mark hstate as isolated likes normal pages for >> prohibiting >> new allocation at first. > > It seems that alloc_migrate_target() calls alloc_page() for normal pages > and the destination pages can be in the same node with the source pages > (new page allocation from the same memblock are prohibited.)
No. It can't. memory hotplug change buddy attribute to MIGRATE_ISOLTE at first. then alloc_page() never allocate from source node. however huge page don't use buddy. then we need another trick. > So if we want to avoid new page allocation from the same node, > this is the problem both for normal and huge pages. > > BTW, is it correct to think that all users of memory hotplug assume > that they want to hotplug a whole node (not the part of it?) Both are valid use case. admin can isolate a part of memory for isolating broken memory range. but I'm sure almost user want to remove whole node. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
