aha/mm
Miao Xie 58568d2a82 cpuset,mm: update tasks' mems_allowed in time
Fix allocating page cache/slab object on the unallowed node when memory
spread is set by updating tasks' mems_allowed after its cpuset's mems is
changed.

In order to update tasks' mems_allowed in time, we must modify the code of
memory policy.  Because the memory policy is applied in the process's
context originally.  After applying this patch, one task directly
manipulates anothers mems_allowed, and we use alloc_lock in the
task_struct to protect mems_allowed and memory policy of the task.

But in the fast path, we didn't use lock to protect them, because adding a
lock may lead to performance regression.  But if we don't add a lock,the
task might see no nodes when changing cpuset's mems_allowed to some
non-overlapping set.  In order to avoid it, we set all new allowed nodes,
then clear newly disallowed ones.

[lee.schermerhorn@hp.com:
  The rework of mpol_new() to extract the adjusting of the node mask to
  apply cpuset and mpol flags "context" breaks set_mempolicy() and mbind()
  with MPOL_PREFERRED and a NULL nodemask--i.e., explicit local
  allocation.  Fix this by adding the check for MPOL_PREFERRED and empty
  node mask to mpol_new_mpolicy().

  Remove the now unneeded 'nodes = NULL' from mpol_new().

  Note that mpol_new_mempolicy() is always called with a non-NULL
  'nodes' parameter now that it has been removed from mpol_new().
  Therefore, we don't need to test nodes for NULL before testing it for
  'empty'.  However, just to be extra paranoid, add a VM_BUG_ON() to
  verify this assumption.]
[lee.schermerhorn@hp.com:

  I don't think the function name 'mpol_new_mempolicy' is descriptive
  enough to differentiate it from mpol_new().

  This function applies cpuset set context, usually constraining nodes
  to those allowed by the cpuset.  However, when the 'RELATIVE_NODES flag
  is set, it also translates the nodes.  So I settled on
  'mpol_set_nodemask()', because the comment block for mpol_new() mentions
  that we need to call this function to "set nodes".

  Some additional minor line length, whitespace and typo cleanup.]
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Paul Menage <menage@google.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-16 19:47:31 -07:00
..
allocpercpu.c percpu: __percpu_depopulate_mask can take a const mask 2009-04-06 13:44:15 -07:00
backing-dev.c block: change the request allocation/congestion logic to be sync/async based 2009-04-06 08:04:53 -07:00
bootmem.c bootmem: fix slab fallback on numa 2009-06-11 19:15:54 +03:00
bounce.c Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block 2009-06-11 11:10:35 -07:00
debug-pagealloc.c generic debug pagealloc 2009-04-01 08:59:13 -07:00
dmapool.c
fadvise.c readahead: move max_sane_readahead() calls into force_page_cache_readahead() 2009-06-16 19:47:28 -07:00
failslab.c kmemtrace, mm: fix slab.h dependency problem in mm/failslab.c 2009-04-03 12:23:01 +02:00
filemap.c readahead: enforce full sync mmap readahead size 2009-06-16 19:47:30 -07:00
filemap_xip.c mm: do_xip_mapping_read: fix length calculation 2009-04-02 19:04:49 -07:00
fremap.c Do not account for the address space used by hugetlbfs using VM_ACCOUNT 2009-02-10 10:48:42 -08:00
highmem.c mm: introduce debug_kmap_atomic 2009-04-01 08:59:14 -07:00
hugetlb.c mm: account for MAP_SHARED mappings using VM_MAYSHARE and not VM_SHARED in hugetlbfs 2009-05-29 08:40:03 -07:00
init-mm.c mm: consolidate init_mm definition 2009-06-16 19:47:28 -07:00
internal.h nommu: there is no mlock() for NOMMU, so don't provide the bits 2009-04-01 08:59:14 -07:00
Kconfig security: use mmap_min_addr indepedently of security models 2009-06-04 12:07:48 +10:00
Kconfig.debug generic debug pagealloc: build fix 2009-04-02 19:04:48 -07:00
kmemleak-test.c kmemleak: Simple testing module for kmemleak 2009-06-11 17:04:19 +01:00
kmemleak.c kmemleak: Add the base support 2009-06-11 17:03:28 +01:00
maccess.c [S390] maccess: add weak attribute to probe_kernel_write 2009-06-12 10:27:37 +02:00
madvise.c readahead: move max_sane_readahead() calls into force_page_cache_readahead() 2009-06-16 19:47:28 -07:00
Makefile mm: consolidate init_mm definition 2009-06-16 19:47:28 -07:00
memcontrol.c memcg: fix build warning and avoid checking for mem != null again and again 2009-05-29 08:40:03 -07:00
memory.c mm: clean up get_user_pages_fast() documentation 2009-06-16 19:47:30 -07:00
memory_hotplug.c mm: remove GFP_HIGHUSER_PAGECACHE 2009-01-06 15:59:01 -08:00
mempolicy.c cpuset,mm: update tasks' mems_allowed in time 2009-06-16 19:47:31 -07:00
mempool.c
migrate.c FS-Cache: Recruit a page flags for cache management 2009-04-03 16:42:36 +01:00
mincore.c [CVE-2009-0029] System call wrappers part 14 2009-01-14 14:15:24 +01:00
mlock.c x86, bts, mm: clean up buffer allocation 2009-04-24 10:18:52 +02:00
mm_init.c
mmap.c Merge branch 'perfcounters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-06-11 14:01:07 -07:00
mmu_notifier.c
mmzone.c [ARM] Double check memmap is actually valid with a memmap has unexpected holes V2 2009-05-18 11:22:24 +01:00
mprotect.c perf_counter: Add mmap event hooks to mprotect() 2009-06-08 23:10:43 +02:00
mremap.c [CVE-2009-0029] System call wrappers part 13 2009-01-14 14:15:23 +01:00
msync.c [CVE-2009-0029] System call wrappers part 13 2009-01-14 14:15:23 +01:00
nommu.c nommu: Provide mmap_min_addr definition. 2009-06-10 09:24:09 +10:00
oom_kill.c oom: fix possible oom_dump_tasks NULL pointer 2009-05-29 08:40:01 -07:00
page-writeback.c mm/page-writeback.c: dirty limit type should be unsigned long 2009-06-16 19:47:31 -07:00
page_alloc.c cpuset,mm: update tasks' mems_allowed in time 2009-06-16 19:47:31 -07:00
page_cgroup.c memcg: fix page_cgroup fatal error in FLATMEM 2009-06-12 11:00:54 +03:00
page_io.c block: fix bad definition of BIO_RW_SYNC 2009-02-18 10:32:00 +01:00
page_isolation.c
pagewalk.c
pdflush.c Revert "mm: add /proc controls for pdflush threads" 2009-05-15 11:32:24 +02:00
percpu.c percpu: remove rbtree and use page->index instead 2009-04-08 18:31:31 +02:00
prio_tree.c
quicklist.c cpumask: replace node_to_cpumask with cpumask_of_node. 2009-03-13 14:49:46 +10:30
readahead.c readahead: introduce context readahead algorithm 2009-06-16 19:47:30 -07:00
rmap.c hugh: update email address 2009-05-21 13:14:32 -07:00
shmem.c integrity: move ima_counts_get 2009-05-22 09:45:33 +10:00
shmem_acl.c
slab.c slab: setup cpu caches later on when interrupts are enabled 2009-06-12 18:53:58 +03:00
slob.c kmemleak: Add the slob memory allocation/freeing hooks 2009-06-11 17:03:30 +01:00
slub.c slab,slub: don't enable interrupts during early boot 2009-06-12 18:53:33 +03:00
sparse-vmemmap.c
sparse.c mm: mminit_validate_memmodel_limits(): remove redundant test 2009-04-01 08:59:11 -07:00
swap.c mm: fix Committed_AS underflow on large NR_CPUS environment 2009-05-02 15:36:10 -07:00
swap_state.c memcg: fix deadlock between lock_page_cgroup and mapping tree_lock 2009-05-29 08:40:02 -07:00
swapfile.c PM/hibernate: fix "swap breaks after hibernation failures" 2009-02-21 14:17:17 -08:00
thrash.c
truncate.c memcg: fix deadlock between lock_page_cgroup and mapping tree_lock 2009-05-29 08:40:02 -07:00
util.c mm: clean up get_user_pages_fast() documentation 2009-06-16 19:47:30 -07:00
vmalloc.c Merge branch 'for-linus' of git://linux-arm.org/linux-2.6 2009-06-11 14:15:57 -07:00
vmscan.c vmscan: low order lumpy reclaim also should use PAGEOUT_IO_SYNC 2009-06-16 19:47:31 -07:00
vmstat.c [ARM] Double check memmap is actually valid with a memmap has unexpected holes V2 2009-05-18 11:22:24 +01:00