On 12/12/2013 09:37 AM, Christoph Lameter wrote: > On Tue, 10 Dec 2013, Dave Hansen wrote: >> See? *EVERYTHING* is overridden by at least one of the sl?b allocators >> except ->flags. In other words, there *ARE* no relationships when it >> comes to the sl?bs, except for page->flags. > > Slab objects can be used for I/O and then the page fields become > important.
OK, which fields? How are they important? Looking at 'struct page', I don't see any fields other than ->flags that the slab allocators leave alone. I do see some refcounting (page->_count) done on request_queue->dma_drain_buffer which is kmalloc()'d. Although, I'm a bit skeptical that this is correct or has been audited because the slabs do seem to write over this storage. Anything needing to do per-page could probably be converted over to a raw alloc_pages() anyway because it couldn't possibly be doing sub-page-size allocations. What other cases were you thinking of? -- 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/
