Hi Tang, On 2013/6/13 21:03, Tang Chen wrote: > The following patch-set from Yinghai allocates pagetables to local nodes. > v1: https://lkml.org/lkml/2013/3/7/642 > v2: https://lkml.org/lkml/2013/3/10/47 > v3: https://lkml.org/lkml/2013/4/4/639 > v4: https://lkml.org/lkml/2013/4/11/829 > > Since pagetable pages are used by the kernel, they cannot be offlined. > As a result, they cannot be hot-remove. > > This patch fix this problem with the following solution: > > 1. Introduce a new bootmem type LOCAL_NODE_DATAL, and register local > pagetable pages as LOCAL_NODE_DATAL by setting page->lru.next to > LOCAL_NODE_DATAL, just like we register SECTION_INFO pages. > > 2. Skip LOCAL_NODE_DATAL pages in offline/online procedures. When the > whole memory block they reside in is offlined, the kernel can > still access the pagetables. > (This changes the semantics of offline/online a little bit.) > > 3. Do not free LOCAL_NODE_DATAL pages to buddy system because they > were skipped when in offline/online procedures. The memory block > they reside in could have been offlined. > s/LOCAL_NODE_DATAL/LOCAL_NODE_DATA > Anyway, this problem should be fixed. Any better idea is welcome. > > Change log: > v1 -> v2: > patch2: As suggested by Wu Jianguo, define a macro to check if a page > cantains local node data. > patch4: As suggested by Wu Jianguo, prevent freeing LOCAL_NODE_DATA > pages in free_pagetable() instead of in put_page_bootmem(). > > Tang Chen (4): > bootmem, mem-hotplug: Register local pagetable pages with > LOCAL_NODE_DATA when freeing bootmem. > mem-hotplug: Skip LOCAL_NODE_DATA pages in memory offline procedure. > mem-hotplug: Skip LOCAL_NODE_DATA pages in memory online procedure. > mem-hotplug: Do not free LOCAL_NODE_DATA pages to buddy system in > hot-remove procedure. > > arch/x86/mm/init_64.c | 10 +++++++- > include/linux/memblock.h | 22 +++++++++++++++++ > include/linux/memory_hotplug.h | 20 +++++++++++++-- > mm/memblock.c | 52 ++++++++++++++++++++++++++++++++++++++++ > mm/memory_hotplug.c | 31 +++++++++++++++++++++++ > mm/page_alloc.c | 15 ++++++++++- > mm/page_isolation.c | 5 ++++ > 7 files changed, 149 insertions(+), 6 deletions(-) > > -- > 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> > > . > -- 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>