5fcbb23050
Policy contextualization is only useful for task based policies and not for vma based policies. It may be useful to define allowed nodes that are not accessible from this thread because other threads may have access to these nodes. Without this patch strange memory policy situations may cause an application to fail with out of memory. Example: Let's say we have two threads A and B that share the same address space and a huge array computational array X. Thread A is restricted by its cpuset to nodes 0 and 1 and thread B is restricted by its cpuset to nodes 2 and 3. Thread A now wants to restrict allocations to the first node and thus applies a BIND policy on X to node 0 and 2. The cpuset limits this to node 0. Thus pages for X must be allocated on node 0 now. Thread B now touches a page that has never been used in X and faults in a page. According to the BIND policy of the vma for X the page must be allocated on page 0. However, the cpuset of B does not allow allocation on 0 and 1. Now the application fails in alloc_pages with out of memory. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| bootmem.c | ||
| fadvise.c | ||
| filemap_xip.c | ||
| filemap.c | ||
| filemap.h | ||
| fremap.c | ||
| highmem.c | ||
| hugetlb.c | ||
| internal.h | ||
| Kconfig | ||
| madvise.c | ||
| Makefile | ||
| memory_hotplug.c | ||
| memory.c | ||
| mempolicy.c | ||
| mempool.c | ||
| mincore.c | ||
| mlock.c | ||
| mmap.c | ||
| mprotect.c | ||
| mremap.c | ||
| msync.c | ||
| nommu.c | ||
| oom_kill.c | ||
| page_alloc.c | ||
| page_io.c | ||
| page-writeback.c | ||
| pdflush.c | ||
| prio_tree.c | ||
| readahead.c | ||
| rmap.c | ||
| shmem.c | ||
| slab.c | ||
| sparse.c | ||
| swap_state.c | ||
| swap.c | ||
| swapfile.c | ||
| thrash.c | ||
| tiny-shmem.c | ||
| truncate.c | ||
| vmalloc.c | ||
| vmscan.c | ||