Messages in this thread | | | Date | Wed, 16 Aug 2006 16:00:26 +0400 | From | Evgeniy Polyakov <> | Subject | Re: [PATCH 1/1] network memory allocator. |
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On Wed, Aug 16, 2006 at 01:27:02PM +0200, Arnd Bergmann (arnd@arndb.de) wrote: > On Wednesday 16 August 2006 11:00, Evgeniy Polyakov wrote: > > There is drawback here - if data was allocated on CPU wheere NIC is > > "closer" and then processed on different CPU it will cost more than > > in case where buffer was allocated on CPU where it will be processed. > > > > But from other point of view, most of the adapters preallocate set of > > skbs, and with msi-x help there will be a possibility to bind irq and > > processing to the CPU where data was origianlly allocated. > > > > So I would like to know how to determine which node should be used for > > allocation. Changes of __get_user_pages() to alloc_pages_node() are > > trivial. > > There are two separate memory areas here: Your own metadata used by the > allocator and the memory used for skb data. > > avl_node_array[cpu] and avl_container_array[cpu] are only designed to > be accessed only by the local cpu, so these should be done like > > avl_node_array[cpu] = kmalloc_node(AVL_NODE_PAGES * sizeof(void *), > GFP_KERNEL, cpu_to_node(cpu)); > > or you could make the whole array DEFINE_PER_CPU(void *, which would > waste some space in the kernel object file. > > Now for the actual pages you get with __get_free_pages(), doing the > same (alloc_pages_node), will help accessing your avl_container > members, but may not be the best solution for getting the data > next to the network adapter.
I can create it with numa_node_id() right now and later, if there will exsist some helper to match netdev->node, it can be used instead.
> Arnd <><
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