linux-toradex.git/mm, branch v2.6.33.2

tmpfs: cleanup mpol_parse_str()

2010-04-01T23:01:32+00:00

commit 926f2ae04f183098cf9a30521776fb2759c8afeb upstream.

mpol_parse_str() made lots 'err' variable related bug.  Because it is ugly
and reviewing unfriendly.

This patch simplifies it.

Signed-off-by: KOSAKI Motohiro 
Cc: Ravikiran Thirumalai 
Cc: Christoph Lameter 
Cc: Mel Gorman 
Acked-by: Lee Schermerhorn 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tmpfs: handle MPOL_LOCAL mount option properly

2010-04-01T23:01:31+00:00

commit 12821f5fb942e795f8009ece14bde868893bd811 upstream.

commit 71fe804b6d5 (mempolicy: use struct mempolicy pointer in
shmem_sb_info) added mpol=local mount option.  but its feature is broken
since it was born.  because such code always return 1 (i.e.  mount
failure).

This patch fixes it.

Signed-off-by: KOSAKI Motohiro 
Cc: Ravikiran Thirumalai 
Cc: Christoph Lameter 
Cc: Mel Gorman 
Acked-by: Lee Schermerhorn 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tmpfs: mpol=bind:0 don't cause mount error.

2010-04-01T23:01:31+00:00

commit d69b2e63e9172afb4d07c305601b79a55509ac4c upstream.

Currently, following mount operation cause mount error.

% mount -t tmpfs -ompol=bind:0 none /tmp

Because commit 71fe804b6d5 (mempolicy: use struct mempolicy pointer in
shmem_sb_info) corrupted MPOL_BIND parse code.

This patch restore the needed one.

Signed-off-by: KOSAKI Motohiro 
Cc: Ravikiran Thirumalai 
Cc: Christoph Lameter 
Cc: Mel Gorman 
Acked-by: Lee Schermerhorn 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tmpfs: fix oops on mounts with mpol=default

2010-04-01T23:01:30+00:00

commit 413b43deab8377819aba1dbad2abf0c15d59b491 upstream.

Fix an 'oops' when a tmpfs mount point is mounted with the mpol=default
mempolicy.

Upon remounting a tmpfs mount point with 'mpol=default' option, the mount
code crashed with a null pointer dereference.  The initial problem report
was on 2.6.27, but the problem exists in mainline 2.6.34-rc as well.  On
examining the code, we see that mpol_new returns NULL if default mempolicy
was requested.  This 'NULL' mempolicy is accessed to store the node mask
resulting in oops.

The following patch fixes it.

Signed-off-by: Ravikiran Thirumalai 
Signed-off-by: KOSAKI Motohiro 
Cc: Christoph Lameter 
Cc: Mel Gorman 
Acked-by: Lee Schermerhorn 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

slab: initialize unused alien cache entry as NULL at alloc_alien_cache().

2010-03-15T16:05:55+00:00

commit f3186a9c51eabe75b2780153ed7f07778d78b16e upstream.

Comparing with existing code, it's a simpler way to use kzalloc_node()
to ensure that each unused alien cache entry is NULL.

CC: Eric Dumazet 
Acked-by: Andi Kleen 
Acked-by: Christoph Lameter 
Acked-by: Matt Mackall 
Signed-off-by: Haicheng Li 
Signed-off-by: Pekka Enberg 
Signed-off-by: Greg Kroah-Hartman

readahead: introduce FMODE_RANDOM for POSIX_FADV_RANDOM

2010-03-15T16:05:54+00:00

commit 0141450f66c3c12a3aaa869748caa64241885cdf upstream.

This fixes inefficient page-by-page reads on POSIX_FADV_RANDOM.

POSIX_FADV_RANDOM used to set ra_pages=0, which leads to poor performance:
a 16K read will be carried out in 4 _sync_ 1-page reads.

In other places, ra_pages==0 means
- it's ramfs/tmpfs/hugetlbfs/sysfs/configfs
- some IO error happened
where multi-page read IO won't help or should be avoided.

POSIX_FADV_RANDOM actually want a different semantics: to disable the
*heuristic* readahead algorithm, and to use a dumb one which faithfully
submit read IO for whatever application requests.

So introduce a flag FMODE_RANDOM for POSIX_FADV_RANDOM.

Note that the random hint is not likely to help random reads performance
noticeably.  And it may be too permissive on huge request size (its IO
size is not limited by read_ahead_kb).

In Quentin's report (http://lkml.org/lkml/2009/12/24/145), the overall
(NFS read) performance of the application increased by 313%!

Tested-by: Quentin Barnes 
Signed-off-by: Wu Fengguang 
Cc: Nick Piggin 
Cc: Andi Kleen 
Cc: Steven Whitehouse 
Cc: David Howells 
Cc: Jonathan Corbet 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Trond Myklebust 
Cc: Chuck Lever 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

memcg: fix oom killing a child process in an other cgroup

2010-02-23T03:50:34+00:00

Presently the oom-killer is memcg aware and it finds the worst process
from processes under memcg(s) in oom.  Then, it kills victim's child
first.

It may kill a child in another cgroup and may not be any help for
recovery.  And it will break the assumption users have.

This patch fixes it.

Signed-off-by: KAMEZAWA Hiroyuki 
Reviewed-by: Minchan Kim 
Cc: Balbir Singh 
Reviewed-by: Daisuke Nishimura 
Acked-by: David Rientjes 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: Make copy_from_user() in migrate.c statically predictable

2010-02-21T16:57:08+00:00

x86-32 has had a static test for copy_on_user() overflow for a while.
This test currently fails in mm/migrate.c resulting in an
allyesconfig/allmodconfig build failure on x86-32:

In function ‘copy_from_user’,
    inlined from ‘do_pages_stat’ at
    /home/hpa/kernel/git/mm/migrate.c:1012:
/home/hpa/kernel/git/arch/x86/include/asm/uaccess_32.h:212: error:
    call to ‘copy_from_user_overflow’ declared

Make the logic more explicit and therefore easier for gcc to
understand.

v2: rewrite the loop entirely using a more normal structure for a
    chunked-data loop (Linus Torvalds)

Reported-by: Len Brown 
Signed-off-by: H. Peter Anvin 
Reviewed-and-Tested-by: KOSAKI Motohiro 
Cc: Arjan van de Ven 
Cc: Andrew Morton 
Cc: Christoph Lameter 
Cc: Hugh Dickins 
Cc: Rik van Riel 
Signed-off-by: Linus Torvalds

Fix potential crash with sys_move_pages

2010-02-06T21:00:37+00:00

We incorrectly depended on the 'node_state/node_isset()' functions
testing the node range, rather than checking it explicitly.  That's not
reliable, even if it might often happen to work.  So do the proper
explicit test.

Reported-by: Marcus Meissner 
Acked-and-tested-by: Brice Goglin 
Acked-by: Hugh Dickins 
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds

hugetlb: fix section mismatches

2010-02-03T02:11:22+00:00

hugetlb_sysfs_add_hstate is called by hugetlb_register_node directly
during init and also indirectly via sysfs after init.

This patch removes the __init tag from hugetlb_sysfs_add_hstate.

Signed-off-by: Jeff Mahoney 
Cc: Lee Schermerhorn 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds