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12 years agocgroups: add res_counter_write_u64() API
Frederic Weisbecker [Mon, 24 Oct 2011 14:59:55 +0000 (01:59 +1100)]
cgroups: add res_counter_write_u64() API

Extend the resource counter API with a mirror of res_counter_read_u64() to
make it handy to update a resource counter value from a cgroup subsystem
u64 value file.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul Menage <paul@paulmenage.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Aditya Kali <adityakali@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Tim Hockin <thockin@hockin.org>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agocgroup/kmemleak: Annotate alloc_page() for cgroup allocations
Steven Rostedt [Mon, 24 Oct 2011 14:59:55 +0000 (01:59 +1100)]
cgroup/kmemleak: Annotate alloc_page() for cgroup allocations

When the cgroup base was allocated with kmalloc, it was necessary to
annotate the variable with kmemleak_not_leak().  But because it has
recently been changed to be allocated with alloc_page() (which skips
kmemleak checks) causes a warning on boot up.

I was triggering this output:

 allocated 8388608 bytes of page_cgroup
 please try 'cgroup_disable=memory' option if you don't want memory cgroups
 kmemleak: Trying to color unknown object at 0xf5840000 as Grey
 Pid: 0, comm: swapper Not tainted 3.0.0-test #12
 Call Trace:
  [<c17e34e6>] ? printk+0x1d/0x1f^M
  [<c10e2941>] paint_ptr+0x4f/0x78
  [<c178ab57>] kmemleak_not_leak+0x58/0x7d
  [<c108ae9f>] ? __rcu_read_unlock+0x9/0x7d
  [<c1cdb462>] kmemleak_init+0x19d/0x1e9
  [<c1cbf771>] start_kernel+0x346/0x3ec
  [<c1cbf1b4>] ? loglevel+0x18/0x18
  [<c1cbf0aa>] i386_start_kernel+0xaa/0xb0

After a bit of debugging I tracked the object 0xf840000 (and others) down
to the cgroup code.  The change from allocating base with kmalloc to
alloc_page() has the base not calling kmemleak_alloc() which adds the
pointer to the object_tree_root, but kmemleak_not_leak() adds it to the
crt_early_log[] table.  On kmemleak_init(), the entry is found in the
early_log[] but not the object_tree_root, and this error message is
displayed.

If alloc_page() fails then it defaults back to vmalloc() which still uses
the kmemleak_alloc() which makes us still need the kmemleak_not_leak()
call.  The solution is to call the kmemleak_alloc() directly if the
alloc_page() succeeds.

Reviewed-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agocgroups: don't attach task to subsystem if migration failed
Ben Blum [Mon, 24 Oct 2011 14:59:55 +0000 (01:59 +1100)]
cgroups: don't attach task to subsystem if migration failed

If a task has exited to the point it has called cgroup_exit() already,
then we can't migrate it to another cgroup anymore.

This can happen when we are attaching a task to a new cgroup between the
call to ->can_attach_task() on subsystems and the migration that is
eventually tried in cgroup_task_migrate().

In this case cgroup_task_migrate() returns -ESRCH and we don't want to
attach the task to the subsystems because the attachment to the new cgroup
itself failed.

Fix this by only calling ->attach_task() on the subsystems if the cgroup
migration succeeded.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Acked-by: Paul Menage <paul@paulmenage.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agocgroups: more safe tasklist locking in cgroup_attach_proc
Ben Blum [Mon, 24 Oct 2011 14:59:54 +0000 (01:59 +1100)]
cgroups: more safe tasklist locking in cgroup_attach_proc

Fix unstable tasklist locking in cgroup_attach_proc.

According to this thread - https://lkml.org/lkml/2011/7/27/243 - RCU is
not sufficient to guarantee the tasklist is stable w.r.t.  de_thread and
exit.  Taking tasklist_lock for reading, instead of rcu_read_lock, ensures
proper exclusion.

Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Acked-by: Paul Menage <paul@paulmenage.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agohfs: fix hfs_find_init() sb->ext_tree NULL ptr oops
Phillip Lougher [Mon, 24 Oct 2011 14:59:48 +0000 (01:59 +1100)]
hfs: fix hfs_find_init() sb->ext_tree NULL ptr oops

Clement Lecigne reports a filesystem which causes a kernel oops in
hfs_find_init() trying to dereference sb->ext_tree which is NULL.

This proves to be because the filesystem has a corrupted MDB extent
record, where the extents file does not fit into the first three extents
in the file record (the first blocks).

In hfs_get_block() when looking up the blocks for the extent file
(HFS_EXT_CNID), it fails the first blocks special case, and falls through
to the extent code (which ultimately calls hfs_find_init()) which is in
the process of being initialised.

Hfs avoids this scenario by always having the extents b-tree fitting into
the first blocks (the extents B-tree can't have overflow extents).

The fix is to check at mount time that the B-tree fits into first blocks,
i.e.  fail if HFS_I(inode)->alloc_blocks >= HFS_I(inode)->first_blocks

Note, the existing commit 47f365eb57573 ("hfs: fix oops on mount with
corrupted btree extent records") becomes subsumed into this as a special
case, but only for the extents B-tree (HFS_EXT_CNID), it is perfectly
acceptable for the catalog B-Tree file to grow beyond three extents, with
the remaining extent descriptors in the extents overfow.

This fixes CVE-2011-2203

Reported-by: Clement LECIGNE <clement.lecigne@netasq.com>
Signed-off-by: Phillip Lougher <plougher@redhat.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoisofs: add readpages support
Namjae Jeon [Mon, 24 Oct 2011 14:59:06 +0000 (01:59 +1100)]
isofs: add readpages support

Use mpage_readpages() instead of multiple calls to isofs_readpage() to
reduce the CPU utilization and make performance higher.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agominix: describe usage of different magic numbers
Sami Kerola [Mon, 24 Oct 2011 14:59:05 +0000 (01:59 +1100)]
minix: describe usage of different magic numbers

One can get this information from minix/inode.c, but adding the
explanations at the definition sites is more appropriate.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/rtc/rtc-mc13xxx.c: move probe and remove callbacks to .init.text and .exit...
Uwe Kleine-König [Mon, 24 Oct 2011 14:59:05 +0000 (01:59 +1100)]
drivers/rtc/rtc-mc13xxx.c: move probe and remove callbacks to .init.text and .exit.text

The driver is added using platform_driver_probe(), so the callbacks can be
discarded more aggessively.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agortc: add initial support for mcp7941x parts
David Anders [Mon, 24 Oct 2011 14:59:04 +0000 (01:59 +1100)]
rtc: add initial support for mcp7941x parts

Add initial support for the microchip mcp7941x series of real time clocks.

The mcp7941x series is generally compatible with the ds1307 and ds1337 rtc
devices from dallas semiconductor.  minor differences include a backup
battery enable bit, and the polarity of the oscillator enable bit.

Signed-off-by: David Anders <danders.dev@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/rtc/class.c: convert idr to ida and use ida_simple_get()
Jonathan Cameron [Mon, 24 Oct 2011 14:59:04 +0000 (01:59 +1100)]
drivers/rtc/class.c: convert idr to ida and use ida_simple_get()

This is the one use of an ida that doesn't retry on receiving -EAGAIN.
I'm assuming do so will cause no harm and may help on a rare occasion.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agooprofilefs: handle zero-length writes
Mike Waychison [Mon, 24 Oct 2011 14:59:04 +0000 (01:59 +1100)]
oprofilefs: handle zero-length writes

Currently in oprofilefs, files that use ulong_fops mis-handle writes of
zero length.  A count of 0 causes oprofilefs_ulong_from_user to return 0
(success), which then leads to oprofile_set_ulong being called to stuff
"value" into file->private_data without it being initialized.

Fix this by moving the check for a zero-length write up into
ulong_write_file.

Signed-off-by: Mike Waychison <mikew@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoinit/do_mounts_rd.c: fix ramdisk identification for padded cramfs
Neil Armstrong [Mon, 24 Oct 2011 14:59:03 +0000 (01:59 +1100)]
init/do_mounts_rd.c: fix ramdisk identification for padded cramfs

When a cramfs ramdisk padded with 512 bytes is given to the kernel, the
current identify_ramdisk_image function fails to identify it.

Tested with a padded cramfs image on an ARM based board.

Signed-off-by: Neil Armstrong <narmstrong@neotion.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Davidlohr Bueso <dave@gnu.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoramfs: remove module leftovers
Richard Weinberger [Mon, 24 Oct 2011 14:59:03 +0000 (01:59 +1100)]
ramfs: remove module leftovers

Since ramfs is hard-selected to "y", the module leftovers make no sense.

Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agobinfmt_elf: fix PIE execution with randomization disabled
Jiri Kosina [Mon, 24 Oct 2011 14:59:02 +0000 (01:59 +1100)]
binfmt_elf: fix PIE execution with randomization disabled

The case of address space randomization being disabled in runtime through
randomize_va_space sysctl is not treated properly in load_elf_binary(),
resulting in SIGKILL coming at exec() time for certain PIE-linked binaries
in case the randomization has been disabled at runtime prior to calling
exec().

Handle the randomize_va_space == 0 case the same way as if we were not
supporting .text randomization at all.

Based on original patch by H.J. Lu and Josh Boyer.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: H.J. Lu <hongjiu.lu@intel.com>
Cc: <stable@kernel.org>
Tested-by: Josh Boyer <jwboyer@redhat.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoepoll: limit paths
Jason Baron [Mon, 24 Oct 2011 14:59:02 +0000 (01:59 +1100)]
epoll: limit paths

The current epoll code can be tickled to run basically indefinitely in
both loop detection path check (on ep_insert()), and in the wakeup paths.
The programs that tickle this behavior set up deeply linked networks of
epoll file descriptors that cause the epoll algorithms to traverse them
indefinitely.  A couple of these sample programs have been previously
posted in this thread: https://lkml.org/lkml/2011/2/25/297.

To fix the loop detection path check algorithms, I simply keep track of
the epoll nodes that have been already visited.  Thus, the loop detection
becomes proportional to the number of epoll file descriptor and links.
This dramatically decreases the run-time of the loop check algorithm.  In
one diabolical case I tried it reduced the run-time from 15 mintues (all
in kernel time) to .3 seconds.

Fixing the wakeup paths could be done at wakeup time in a similar manner
by keeping track of nodes that have already been visited, but the
complexity is harder, since there can be multiple wakeups on different
cpus...Thus, I've opted to limit the number of possible wakeup paths when
the paths are created.

This is accomplished, by noting that the end file descriptor points that
are found during the loop detection pass (from the newly added link), are
actually the sources for wakeup events.  I keep a list of these file
descriptors and limit the number and length of these paths that emanate
from these 'source file descriptors'.  In the current implemetation I
allow 1000 paths of length 1, 500 of length 2, 100 of length 3, 50 of
length 4 and 10 of length 5.  Note that it is sufficient to check the
'source file descriptors' reachable from the newly added link, since no
other 'source file descriptors' will have newly added links.  This allows
us to check only the wakeup paths that may have gotten too long, and not
re-check all possible wakeup paths on the system.

In terms of the path limit selection, I think its first worth noting that
the most common case for epoll, is probably the model where you have 1
epoll file descriptor that is monitoring n number of 'source file
descriptors'.  In this case, each 'source file descriptor' has a 1 path of
length 1.  Thus, I believe that the limits I'm proposing are quite
reasonable and in fact may be too generous.  Thus, I'm hoping that the
proposed limits will not prevent any workloads that currently work to
fail.

In terms of locking, I have extended the use of the 'epmutex' to all
epoll_ctl add and remove operations.  Currently its only used in a subset
of the add paths.  I need to hold the epmutex, so that we can correctly
traverse a coherent graph, to check the number of paths.  I believe that
this additional locking is probably ok, since its in the setup/teardown
paths, and doesn't affect the running paths, but it certainly is going to
add some extra overhead.  Also, worth noting is that the epmuex was
recently added to the ep_ctl add operations in the initial path loop
detection code using the argument that it was not on a critical path.

Another thing to note here, is the length of epoll chains that is allowed.
Currently, eventpoll.c defines:

/* Maximum number of nesting allowed inside epoll sets */
#define EP_MAX_NESTS 4

This basically means that I am limited to a graph depth of 5 (EP_MAX_NESTS
+ 1).  However, this limit is currently only enforced during the loop
check detection code, and only when the epoll file descriptors are added
in a certain order.  Thus, this limit is currently easily bypassed.  The
newly added check for wakeup paths, stricly limits the wakeup paths to a
length of 5, regardless of the order in which ep's are linked together.
Thus, a side-effect of the new code is a more consistent enforcement of
the graph depth.

Thus far, I've tested this, using the sample programs previously
mentioned, which now either return quickly or return -EINVAL.  I've also
testing using the piptest.c epoll tester, which showed no difference in
performance.  I've also created a number of different epoll networks and
tested that they behave as expectded.

I believe this solves the original diabolical test cases, while still
preserving the sane epoll nesting.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Nelson Elhage <nelhage@ksplice.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agolib-crc-add-slice-by-8-algorithm-to-crc32c-fix
Andrew Morton [Mon, 24 Oct 2011 14:59:01 +0000 (01:59 +1100)]
lib-crc-add-slice-by-8-algorithm-to-crc32c-fix

don't include asm/msr.h

Cc: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: frank zago <fzago@systemfabricworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agolib/crc: add slice by 8 algorithm to crc32.c
frank zago [Mon, 24 Oct 2011 14:59:01 +0000 (01:59 +1100)]
lib/crc: add slice by 8 algorithm to crc32.c

Add support for slice by 8 to existing crc32 algorithm.  Also modify
gen_crc32table.c to only produce table entries that are actually used.
The parameters CRC_LE_BITS and CRC_BE_BITS determine the number of bits in
the input array that are processed during each step.  Generally the more
bits the faster the algorithm is but the more table data required.

Using an x86_64 Opteron machine running at 2100MHz the following table was
collected with a pre-warmed cache by computing the crc 1000 times on a
buffer of 4096 bytes.

BITS Size LE Cycles/byte BE Cycles/byte
----------------------------------------------
1 873 41.65 34.60
2 1097 25.43 29.61
4 1057 13.29 15.28
8 2913 7.13 8.19
32 9684 2.80 2.82
64 18178 1.53 1.53

BITS is the value of CRC_LE_BITS or CRC_BE_BITS. The old
default was 8 which actually selected the 32 bit algorithm. In
this version the value 8 is used to select the standard
8 bit algorithm and two new values: 32 and 64 are introduced
to select the slice by 4 and slice by 8 algorithms respectively.

Where Size is the size of crc32.o's text segment which includes
code and table data when both LE and BE versions are set to BITS.

The current version of crc32.c by default uses the slice by 4 algorithm
which requires about 2.8 cycles per byte.  The slice by 8 algorithm is
roughly 2X faster and enables packet processing at over 1GB/sec on a
typical 2-3GHz system.

Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agopoll: add poll_requested_events() function
Hans Verkuil [Mon, 24 Oct 2011 14:58:47 +0000 (01:58 +1100)]
poll: add poll_requested_events() function

In some cases the poll() implementation in a driver has to do different
things depending on the events the caller wants to poll for.  An example
is when a driver needs to start a DMA engine if the caller polls for
POLLIN, but doesn't want to do that if POLLIN is not requested but instead
only POLLOUT or POLLPRI is requested.  This is something that can happen
in the video4linux subsystem.

Unfortunately, the current epoll/poll/select implementation doesn't
provide that information reliably.  The poll_table_struct does have it: it
has a key field with the event mask.  But once a poll() call matches one
or more bits of that mask any following poll() calls are passed a NULL
poll_table_struct pointer.

The solution is to set the qproc field to NULL in poll_table_struct once
poll() matches the events, not the poll_table_struct pointer itself.  That
way drivers can obtain the mask through a new poll_requested_events
inline.

The poll_table_struct can still be NULL since some kernel code calls it
internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h).  In
that case poll_requested_events() returns ~0 (i.e.  all events).

Since eventpoll always leaves the key field at ~0 instead of using the
requested events mask, that source was changed as well to properly fill in
the key field.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Jonathan Corbet <corbet@lwn.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agointel_idle: disable auto_demotion for hotplugged CPUs
Shaohua Li [Mon, 24 Oct 2011 14:58:34 +0000 (01:58 +1100)]
intel_idle: disable auto_demotion for hotplugged CPUs

auto_demotion_disable is called only for online CPUs.  For hotplugged
CPUs, we should disable it too.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agointel_idle: fix API misuse
Shaohua Li [Mon, 24 Oct 2011 14:58:33 +0000 (01:58 +1100)]
intel_idle: fix API misuse

smp_call_function() only lets all other CPUs execute a specific function,
while we expect all CPUs do in intel_idle.  Without the fix, we could have
one cpu which has auto_demotion enabled or has no boradcast timer setup.
Usually we don't see impact because auto demotion just harms power and the
intel_idle init is called in CPU 0, where boradcast timer delivers
interrupt, but this still could be a problem.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agohpet: factor timer allocate from open
Magnus Lynch [Mon, 24 Oct 2011 14:58:32 +0000 (01:58 +1100)]
hpet: factor timer allocate from open

The current implementation of the /dev/hpet driver couples opening the
device with allocating one of the (scarce) timers (aka comparators).  This
is a limitation in that the main counter may be valuable to applications
seeking a high-resolution timer who have no use for the interrupt
generating functionality of the comparators.

This patch alters the open semantics so that when the device is opened, no
timer is allocated.  Operations that depend on a timer being in context
implicitly attempt allocating a timer, to maintain backward compatibility.
 There is also an IOCTL (HPET_ALLOC_TIMER _IO) added so that the
allocation may be done explicitly.  (I prefer the explicit open then
allocate pattern but don't know how practical it would be to require all
existing code to be changed.)

/dev/hpet is accessed via mmap().  This is the only interface of /dev/hpet
that is actually used in practice.

[akpm@linux-foundation.org: coding-style tweaks]
[arnd@arndb.de: fix build]
Signed-off-by: Magnus Lynch <maglyx@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoinclude/linux/security.h: fix security_inode_init_security() arg
Andrew Morton [Mon, 24 Oct 2011 14:58:32 +0000 (01:58 +1100)]
include/linux/security.h: fix security_inode_init_security() arg

Make the security_inode_init_security() initxattrs arg const, to match the
non-stubbed version of that function.

Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoselinuxfs: remove custom hex_to_bin()
Andy Shevchenko [Mon, 24 Oct 2011 14:58:31 +0000 (01:58 +1100)]
selinuxfs: remove custom hex_to_bin()

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm: add vm_area_add_early()
Nicolas Pitre [Mon, 24 Oct 2011 14:54:32 +0000 (01:54 +1100)]
mm: add vm_area_add_early()

The existing vm_area_register_early() allows for early vmalloc space
allocation.  However upcoming cleanups in the ARM architecture require
that some fixed locations in the vmalloc area be reserved also very early.

The name "vm_area_register_early" would have been a good name for the
reservation part without the allocation.  Since it is already in use with

Both vm_area_register_early() and vm_area_add_early() can be used together
meaning that the former is now implemented using the later where it is
ensured that no conflicting areas are added, but no attempt is made to
make the allocation scheme in vm_area_register_early() more sophisticated.
After all, you must know what you're doing when using those functions.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agothp: share get_huge_page_tail()
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:24 +0000 (01:54 +1100)]
thp: share get_huge_page_tail()

This avoids duplicating the function in every arch gup_fast.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agosparc: gup_pte_range() support THP based tail recounting
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:24 +0000 (01:54 +1100)]
sparc: gup_pte_range() support THP based tail recounting

Up to this point the code assumed old refcounting for hugepages (pre-thp).
 This updates the code directly to the thp mapcount tail page refcounting.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agos390: gup_huge_pmd() return 0 if pte changes
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:23 +0000 (01:54 +1100)]
s390: gup_huge_pmd() return 0 if pte changes

s390 didn't return 0 in that case, if it's rolling back the *nr pointer it
should also return zero to avoid adding pages to the array at the wrong
offset.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agos390: gup_huge_pmd() support THP tail recounting
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:23 +0000 (01:54 +1100)]
s390: gup_huge_pmd() support THP tail recounting

Up to this point the code assumed old refcounting for hugepages (pre-thp).
This updates the code directly to the thp mapcount tail page refcounting.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agopowerpc: gup_huge_pmd() return 0 if pte changes
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:23 +0000 (01:54 +1100)]
powerpc: gup_huge_pmd() return 0 if pte changes

powerpc didn't return 0 in that case, if it's rolling back the *nr pointer
it should also return zero to avoid adding pages to the array at the wrong
offset.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agopowerpc: gup_hugepte() support THP based tail recounting
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:22 +0000 (01:54 +1100)]
powerpc: gup_hugepte() support THP based tail recounting

Up to this point the code assumed old refcounting for hugepages (pre-thp).
This updates the code directly to the thp mapcount tail page refcounting.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agopowerpc: gup_hugepte() avoid to free the head page too many times
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:22 +0000 (01:54 +1100)]
powerpc: gup_hugepte() avoid to free the head page too many times

We only taken "refs" pins on the head page not "*nr" pins.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agopowerpc: get_hugepte() don't put_page() the wrong page
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:22 +0000 (01:54 +1100)]
powerpc: get_hugepte() don't put_page() the wrong page

"page" may have changed to point to the next hugepage after the loop
completed, The references have been taken on the head page, so the
put_page must happen there too.

This is a longstanding issue pre-thp inclusion.

It's totally unclear how these page_cache_add_speculative and pte_val(pte)
!= pte_val(*ptep) checks are necessary across all the powerpc gup_fast
code, when x86 doesn't need any of that: there's no way the page can be
freed with irq disabled so we're guaranteed the atomic_inc will happen on
a page with page_count > 0 (so not needing the speculative check).  The
pte check is also meaningless on x86: no need to rollback on x86 if the
pte changed, because the pte can still change a CPU tick after the check
succeeded and it won't be rolled back in that case.  The important thing
is we got a reference on a valid page that was mapped there a CPU tick
ago.  So not knowing the soft tlb refill code of ppc64 in great detail I'm
not removing the "speculative" page_count increase and the pte checks
across all the code, but unless there's a strong reason for it they should
be later cleaned up too.

If a pte can change from huge to non-huge (like it could happen with THP)
passing a pte_t *ptep to gup_hugepte() would also require to repeat the
is_hugepd in gup_hugepte(), but that shouldn't happen with hugetlbfs only
so I'm not altering that.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agopowerpc: remove superfluous PageTail checks on the pte gup_fast
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:21 +0000 (01:54 +1100)]
powerpc: remove superfluous PageTail checks on the pte gup_fast

This part of gup_fast doesn't seem capable of handling hugetlbfs ptes,
those should be handled by gup_hugepd only, so these checks are
superfluous.

Plus if this wasn't a noop, it would have oopsed because, the insistence
of using the speculative refcounting would trigger a VM_BUG_ON if a tail
page was encountered in the page_cache_get_speculative().

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm: thp: tail page refcounting fix
Andrea Arcangeli [Mon, 24 Oct 2011 14:54:21 +0000 (01:54 +1100)]
mm: thp: tail page refcounting fix

Michel while working on the working set estimation code, noticed that
calling get_page_unless_zero() on a random pfn_to_page(random_pfn) wasn't
safe, if the pfn ended up being a tail page of a transparent hugepage
under splitting by __split_huge_page_refcount().  He then found the
problem could also theoretically materialize with
page_cache_get_speculative() during the speculative radix tree lookups
that uses get_page_unless_zero() in SMP if the radix tree page is freed
and reallocated and get_user_pages is called on it before
page_cache_get_speculative has a chance to call get_page_unless_zero().

So the best way to fix the problem is to keep page_tail->_count zero at
all times.  This will guarantee that get_page_unless_zero() can never
succeed on any tail page.  page_tail->_mapcount is guaranteed zero and is
unused for all tail pages of a compound page, so we can simply account the
tail page references there and transfer them to tail_page->_count in
__split_huge_page_refcount() (in addition to the head_page->_mapcount).

While debugging this s/_count/_mapcount/ change I also noticed get_page is
called by direct-io.c on pages returned by get_user_pages.  That wasn't
entirely safe because the two atomic_inc in get_page weren't atomic.  As
opposed other get_user_page users like secondary-MMU page fault to
establish the shadow pagetables would never call any superflous get_page
after get_user_page returns.  It's safer to make get_page universally safe
for tail pages and to use get_page_foll() within follow_page (inside
get_user_pages()).  get_page_foll() is safe to do the refcounting for tail
pages without taking any locks because it is run within PT lock protected
critical sections (PT lock for pte and page_table_lock for
pmd_trans_huge).  The standard get_page() as invoked by direct-io instead
will now take the compound_lock but still only for tail pages.  The
direct-io paths are usually I/O bound and the compound_lock is per THP so
very finegrined, so there's no risk of scalability issues with it.  A
simple direct-io benchmarks with all lockdep prove locking and spinlock
debugging infrastructure enabled shows identical performance and no
overhead.  So it's worth it.  Ideally direct-io should stop calling
get_page() on pages returned by get_user_pages().  The spinlock in
get_page() is already optimized away for no-THP builds but doing
get_page() on tail pages returned by GUP is generally a rare operation and
usually only run in I/O paths.

This new refcounting on page_tail->_mapcount in addition to avoiding new
RCU critical sections will also allow the working set estimation code to
work without any further complexity associated to the tail page
refcounting with THP.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm-add-extra-free-kbytes-tunable-update-checkpatch-fixes
Andrew Morton [Mon, 24 Oct 2011 14:54:20 +0000 (01:54 +1100)]
mm-add-extra-free-kbytes-tunable-update-checkpatch-fixes

ERROR: trailing whitespace
#98: FILE: mm/page_alloc.c:5303:
+ * free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so $

ERROR: trailing whitespace
#103: FILE: mm/page_alloc.c:5307:
+int free_kbytes_sysctl_handler(ctl_table *table, int write, $

ERROR: need consistent spacing around '*' (ctx:WxV)
#103: FILE: mm/page_alloc.c:5307:
+int free_kbytes_sysctl_handler(ctl_table *table, int write,
                                          ^

total: 3 errors, 0 warnings, 69 lines checked

NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or
      scripts/cleanfile

./patches/mm-add-extra-free-kbytes-tunable-update.patch has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm-add-extra-free-kbytes-tunable-update
Rik van Riel [Mon, 24 Oct 2011 14:54:20 +0000 (01:54 +1100)]
mm-add-extra-free-kbytes-tunable-update

All the fixes suggested by Andrew Morton.   Not much of a changelog
since the patch should probably be folded into
mm-add-extra-free-kbytes-tunable.patch

Thank you for pointing these out, Andrew.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm: add extra free kbytes tunable
Rik van Riel [Mon, 24 Oct 2011 14:54:20 +0000 (01:54 +1100)]
mm: add extra free kbytes tunable

Add a userspace visible knob to tell the VM to keep an extra amount of
memory free, by increasing the gap between each zone's min and low
watermarks.

This is useful for realtime applications that call system calls and have a
bound on the number of allocations that happen in any short time period.
In this application, extra_free_kbytes would be left at an amount equal to
or larger than than the maximum number of allocations that happen in any
burst.

It may also be useful to reduce the memory use of virtual machines
(temporarily?), in a way that does not cause memory fragmentation like
ballooning does.

Testing results from Satoru Moriya:

: I ran some sample workloads and measure memory allocation latency
: (latency of __alloc_page_nodemask()).
: The test is like following:
:
:  - CPU: 1 socket, 4 core
:  - Memory: 4GB
:
:  - Background load:
:    $ dd if=3D/dev/zero of=3D/tmp/tmp1
:    $ dd if=3D/dev/zero of=3D/tmp/tmp2
:    $ dd if=3D/dev/zero of=3D/tmp/tmp3
:
:  - Main load:
:    $ mapped-file-stream 1 $((1024 * 1024 * 640))  --(*)
:
:  (*) This is made by Johannes Weiner
:      https://lkml.org/lkml/2010/8/30/226
:
:      It allocates/access 640MByte memory at a burst.
:
: The result is follwoing:
:
:                                |         |  extra   |
:                                | default |  kbytes  |
: --------------------------------------------------------------
: min_free_kbytes                |    8113 |   8113   |
: extra_free_kbytes              |       0 | 640*1024 | (KB)
: --------------------------------------------------------------
: worst latency                  | 517.762 |  20.775  | (usec)
: --------------------------------------------------------------
: vmstat result                  |         |          |
:  nr_vmscan_write               |       0 |      0   |
:  pgsteal_dma                   |       0 |      0   |
:  pgsteal_dma32                 |  143667 | 144882   |
:  pgsteal_normal                |   31486 |  27001   |
:  pgsteal_movable               |       0 |      0   |
:  pgscan_kswapd_dma             |       0 |      0   |
:  pgscan_kswapd_dma32           |  138617 | 156351   |
:  pgscan_kswapd_normal          |   30593 |  27955   |
:  pgscan_kswapd_movable         |       0 |      0   |
:  pgscan_direct_dma             |       0 |      0   |
:  pgscan_direct_dma32           |    5050 |      0   |
:  pgscan_direct_normal          |     896 |      0   |
:  pgscan_direct_movable         |       0 |      0   |
:  kswapd_steal                  |  169207 | 171883   |
:  kswapd_inodesteal             |       0 |      0   |
:  kswapd_low_wmark_hit_quickly  |      43 |     45   |
:  kswapd_high_wmark_hit_quickly |       1 |      0   |
:  allocstall                    |      32 |      0   |
:
:
: As you can see, in the default case there were 32 direct reclaim
: (allocstal= l) and its worst latency was 517.762 usecs.  This value may be
: larger if a process would sleep or issue I/O in the direct reclaim path.
: OTOH, ii the other case where I add extra free bytes, there were no direct
: reclaim and its worst latency was 20.775 usecs.
:
: In this test case, we can avoid direct reclaim and keep a latency low.

Signed-off-by: Rik van Riel<riel@redhat.com>
Acked-by: Johannes Weiner <jweiner@redhat.com>
Tested-by: Satoru Moriya <satoru.moriya@hds.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm: fix page-faults detection in swap-token logic
Konstantin Khlebnikov [Mon, 24 Oct 2011 14:54:19 +0000 (01:54 +1100)]
mm: fix page-faults detection in swap-token logic

After commit v2.6.36-5896-gd065bd8 "mm: retry page fault when blocking on
disk transfer" we usually wait in page-faults without mmap_sem held, so
all swap-token logic was broken, because it based on using
rwsem_is_locked(&mm->mmap_sem) as sign of in progress page-faults.

Add an atomic counter of in progress page-faults for mm to the mm_struct
with swap-token.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm: add free_hot_cold_page_list() helper
Konstantin Khlebnikov [Mon, 24 Oct 2011 14:54:18 +0000 (01:54 +1100)]
mm: add free_hot_cold_page_list() helper

This patch adds helper free_hot_cold_page_list() to free list of 0-order
pages.  It frees pages directly from list without temporary page-vector.
It also calls trace_mm_pagevec_free() to simulate pagevec_free()
behaviour.

bloat-o-meter:

add/remove: 1/1 grow/shrink: 1/3 up/down: 267/-295 (-28)
function                                     old     new   delta
free_hot_cold_page_list                        -     264    +264
get_page_from_freelist                      2129    2132      +3
__pagevec_free                               243     239      -4
split_free_page                              380     373      -7
release_pages                                606     510     -96
free_page_list                               188       -    -188

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agovmscan: activate executable pages after first usage
Konstantin Khlebnikov [Mon, 24 Oct 2011 14:54:12 +0000 (01:54 +1100)]
vmscan: activate executable pages after first usage

Logic added in commit 8cab4754d24a0 ("vmscan: make mapped executable pages
the first class citizen") was noticeably weakened in commit
645747462435d84 ("vmscan: detect mapped file pages used only once").

Currently these pages can become "first class citizens" only after second
usage.  After this patch page_check_references() will activate they after
first usage, and executable code gets yet better chance to stay in memory.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agovmscan: promote shared file mapped pages
Konstantin Khlebnikov [Mon, 24 Oct 2011 14:54:11 +0000 (01:54 +1100)]
vmscan: promote shared file mapped pages

Commit 645747462435 ("vmscan: detect mapped file pages used only once")
greatly decreases lifetime of single-used mapped file pages.
Unfortunately it also decreases life time of all shared mapped file pages.
Because after commit bf3f3bc5e7347 ("mm: don't mark_page_accessed
in fault path") page-fault handler does not mark page active or even
referenced.

Thus page_check_references() activates file page only if it was used twice
while it stays in inactive list, meanwhile it activates anon pages after
first access.  Inactive list can be small enough, this way reclaimer can
accidentally throw away any widely used page if it wasn't used twice in
short period.

After this patch page_check_references() also activate file mapped page at
first inactive list scan if this page is already used multiple times via
several ptes.

I found this while trying to fix degragation in rhel6 (~2.6.32) from rhel5
(~2.6.18).  There a complete mess with >100 web/mail/spam/ftp containers,
they share all their files but there a lot of anonymous pages: ~500mb
shared file mapped memory and 15-20Gb non-shared anonymous memory.  In
this situation major-pagefaults are very costly, because all containers
share the same page.  In my load kernel created a disproportionate
pressure on the file memory, compared with the anonymous, they equaled
only if I raise swappiness up to 150 =)

These patches actually wasn't helped a lot in my problem, but I saw
noticable (10-20 times) reduce in count and average time of
major-pagefault in file-mapped areas.

Actually both patches are fixes for commit v2.6.33-5448-g6457474, because
it was aimed at one scenario (singly used pages), but it breaks the logic
in other scenarios (shared and/or executable pages)

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agovmscan-use-atomic-long-for-shrinker-batching-fix
Andrew Morton [Mon, 24 Oct 2011 14:54:11 +0000 (01:54 +1100)]
vmscan-use-atomic-long-for-shrinker-batching-fix

massage atomic.h inclusions

Cc: Dave Chinner <david@fromorbit.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agovmscan: use atomic-long for shrinker batching
Konstantin Khlebnikov [Mon, 24 Oct 2011 14:54:10 +0000 (01:54 +1100)]
vmscan: use atomic-long for shrinker batching

Use atomic-long operations instead of looping around cmpxchg().

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agovmscan: fix initial shrinker size handling
Konstantin Khlebnikov [Mon, 24 Oct 2011 14:54:10 +0000 (01:54 +1100)]
vmscan: fix initial shrinker size handling

A shrinker function can return -1, means that it cannot do anything
without a risk of deadlock.  For example prune_super() does this if it
cannot grab a superblock refrence, even if nr_to_scan=0.  Currently we
interpret this -1 as a ULONG_MAX size shrinker and evaluate `total_scan'
according to this.  So the next time around this shrinker can cause really
big pressure.  Let's skip such shrinkers instead.

Also make total_scan signed, otherwise the check (total_scan < 0) below
never works.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agomm/page-writeback.c: make determine_dirtyable_memory static again
Johannes Weiner [Mon, 24 Oct 2011 14:54:01 +0000 (01:54 +1100)]
mm/page-writeback.c: make determine_dirtyable_memory static again

The tracing ring-buffer used this function briefly, but not anymore.
Make it local to the writeback code again.

Also, move the function so that no forward declaration needs to be
reintroduced.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/tty/serial/pch_uart.c: add console support
Alexander Stein [Mon, 24 Oct 2011 14:53:55 +0000 (01:53 +1100)]
drivers/tty/serial/pch_uart.c: add console support

Add console support to pch_uart.  To enable append e.g.
console=ttyPCH0,115200 to your kernel command line.

This is not expected work on CM-iTC boards due to their having a different
clock.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoslub: add taint flag outputting to debug paths
Dave Jones [Mon, 24 Oct 2011 14:53:55 +0000 (01:53 +1100)]
slub: add taint flag outputting to debug paths

When we get corruption reports, it's useful to see if the kernel was
tainted, to rule out problems we can't do anything about.

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoslab: add taint flag outputting to debug paths.
Dave Jones [Mon, 24 Oct 2011 14:53:55 +0000 (01:53 +1100)]
slab: add taint flag outputting to debug paths.

When we get corruption reports, it's useful to see if the kernel was
tainted, to rule out problems we can't do anything about.

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/watchdog/w83627hf_wdt.c: implement WDIOC_GETTIMELEFT ioctl support
Greg Lee [Mon, 24 Oct 2011 14:53:54 +0000 (01:53 +1100)]
drivers/watchdog/w83627hf_wdt.c: implement WDIOC_GETTIMELEFT ioctl support

Implement the WDIOC_GETTIMELEFT ioctl, allowing you to check how much time
is left on the watchdog counter before a reset occurs.  A few additional
naming clean-ups requested by Padraig Brady as well.

Signed-off-by: Greg Lee <glee@swspec.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Padraig Brady <P@draigbrady.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoparide: fix potential information leak in pg_read()
Dan Carpenter [Mon, 24 Oct 2011 14:53:54 +0000 (01:53 +1100)]
paride: fix potential information leak in pg_read()

Smatch has a new check for Rosenberg type information leaks where structs
are copied to the user with uninitialized stack data in them.  i In this
case, the pg_write_hdr struct has a hole in it.

struct pg_write_hdr {
        char                       magic;                /*     0     1 */
        char                       func;                 /*     1     1 */
        /* XXX 2 bytes hole, try to pack */
        int                        dlen;                 /*     4     4 */

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agobio: change some signed vars to unsigned
Dan Carpenter [Mon, 24 Oct 2011 14:53:54 +0000 (01:53 +1100)]
bio: change some signed vars to unsigned

This is just a cleanup patch to silence a static checker warning.

The problem is that we cap "nr_iovecs" so it can't be larger than
"UIO_MAXIOV" but we don't check for negative values.  It turns out this is
prevented at other layers, but logically it doesn't make sense to have
negative nr_iovecs so making it unsigned is nicer.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoinclude/linux/bio.h: use a static inline function for bio_integrity_clone()
Stephen Rothwell [Mon, 24 Oct 2011 14:53:53 +0000 (01:53 +1100)]
include/linux/bio.h: use a static inline function for bio_integrity_clone()

When CONFIG_BLK_DEV_INTEGRITY is not set, we get these warnings:

drivers/md/dm.c: In function 'split_bvec':
drivers/md/dm.c:1061:3: warning: statement with no effect
drivers/md/dm.c: In function 'clone_bio':
drivers/md/dm.c:1088:3: warning: statement with no effect

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoblock: add missed trace_block_plug
Shaohua Li [Mon, 24 Oct 2011 14:53:52 +0000 (01:53 +1100)]
block: add missed trace_block_plug

After flush plug list, the list has no request, so we need to add a
trace_block_plug().

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoblock: avoid unnecessary plug list flush
Shaohua Li [Mon, 24 Oct 2011 14:53:52 +0000 (01:53 +1100)]
block: avoid unnecessary plug list flush

get_request_wait() could sleep and flush the plug list.  If the list is
already flushed, don't flush again.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agocciss: auto engage SCSI mid layer at driver load time
Stephen M. Cameron [Mon, 24 Oct 2011 14:53:52 +0000 (01:53 +1100)]
cciss: auto engage SCSI mid layer at driver load time

A long time ago, probably in 2002, one of the distros, or maybe more than
one, loaded block drivers prior to loading the SCSI mid layer.  This meant
that the cciss driver, being a block driver, could not engage the SCSI mid
layer at init time without panicking, and relied on being poked by a
userland program after the system was up (and the SCSI mid layer was
therefore present) to engage the SCSI mid layer.

This is no longer the case, and cciss can safely rely on the SCSI mid
layer being present at init time and engage the SCSI mid layer straight
away.  This means that users will see their tape drives and medium
changers at driver load time without need for a script in /etc/rc.d that
does this:

for x in /proc/driver/cciss/cciss*
do
echo "engage scsi" > $x
done

However, if no tape drives or medium changers are detected, the SCSI mid
layer will not be engaged.  If a tape drive or medium change is later
hot-added to the system it will then be necessary to use the above script
or similar for the device(s) to be acceesible.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoloop-cleanup-set_status-interface-checkpatch-fixes
Andrew Morton [Mon, 24 Oct 2011 14:53:51 +0000 (01:53 +1100)]
loop-cleanup-set_status-interface-checkpatch-fixes

WARNING: line over 80 characters
#120: FILE: drivers/block/loop.c:1388:
+ (struct loop_info __user *) arg);

total: 0 errors, 1 warnings, 92 lines checked

./patches/loop-cleanup-set_status-interface.patch has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoloop: cleanup set_status interface
Dmitry Monakhov [Mon, 24 Oct 2011 14:53:51 +0000 (01:53 +1100)]
loop: cleanup set_status interface

1) Anyone who has read access to loopdev has permission to call set_status
   and may change important parameters such as lo_offset, lo_sizelimit and
   so on, which contradicts to read access pattern and definitely equals
   to write access pattern.
2) Add lo_offset over i_size check to prevent blkdev_size overflow.
   ##Testcase_bagin
   #dd if=/dev/zero of=./file bs=1k count=1
   #losetup /dev/loop0 ./file
   /* userspace_application */
   struct loop_info64 loinf;
   fd = open("/dev/loop0", O_RDONLY);
   ioctl(fd, LOOP_GET_STATUS64, &loinf);
   /* Set offset to any value which is bigger than i_size, and sizelimit
    * to nonzero value*/
   loinf.lo_offset = 4096*1024;
   loinf.lo_sizelimit = 1024;
   ioctl(fd, LOOP_SET_STATUS64, &loinf);
   /* After this loop device will have size similar to 0x7fffffffffxxxx */
   #blockdev --getsz /dev/loop0
   ##OUTPUT: 36028797018955968
   ##Testcase_end

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoloop: prevent information leak after failed read
Dmitry Monakhov [Mon, 24 Oct 2011 14:53:50 +0000 (01:53 +1100)]
loop: prevent information leak after failed read

If read was not fully successful we have to fail whole bio to prevent
information leak of old pages

##Testcase_begin
dd if=/dev/zero of=./file bs=1M count=1
losetup /dev/loop0 ./file -o 4096
truncate -s 0 ./file
# OOps loop offset is now beyond i_size, so read will silently fail.
# So bio's pages would not be cleared, may which result in information leak.
hexdump -C /dev/loop0
##testcase_end

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/message/fusion/mptbase.c: ensure NUL-termination of MptCallbacksName elements
Ferenc Wagner [Mon, 24 Oct 2011 14:53:50 +0000 (01:53 +1100)]
drivers/message/fusion/mptbase.c: ensure NUL-termination of MptCallbacksName elements

I just stumbled upon this while pondering over
https://bugzilla.kernel.org/show_bug.cgi?id=26692 and thought this could
be made better.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Ferenc Wagner <wferi@niif.hu>
Cc: Desai <kashyap.desai@lsi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/scsi/mpt2sas/mpt2sas_base.c: fix mismatch in mpt2sas_base_hard_reset_handler...
Alexey Khoroshilov [Mon, 24 Oct 2011 14:53:49 +0000 (01:53 +1100)]
drivers/scsi/mpt2sas/mpt2sas_base.c: fix mismatch in mpt2sas_base_hard_reset_handler() mutex lock-unlock

If ioc->pci_error_recovery is set, goto out in
mpt2sas_base_hard_reset_handler() leads to unlock unheld
ioc->reset_in_progress_mutex.

Fix the issue by jumping afer mutex_unlock() call.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/scsi/sg.c: convert to kstrtoul_from_user()
Stephen Boyd [Mon, 24 Oct 2011 14:53:49 +0000 (01:53 +1100)]
drivers/scsi/sg.c: convert to kstrtoul_from_user()

Instead of open coding this function use kstrtoul_from_user() directly.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/scsi/osd/osd_uld.c: use ida_simple_get() to handle id
Jonathan Cameron [Mon, 24 Oct 2011 14:53:49 +0000 (01:53 +1100)]
drivers/scsi/osd/osd_uld.c: use ida_simple_get() to handle id

This does involve additional use of the spin lock in idr.c.  Is this an
issue?

Also, some error mangling was needed to keep the interface the same.  Does
this matter or can we return -ENOSPC instead of -EBUSY?

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/scsi/aacraid/commctrl.c: fix mem leak in aac_send_raw_srb()
Jesper Juhl [Mon, 24 Oct 2011 14:53:48 +0000 (01:53 +1100)]
drivers/scsi/aacraid/commctrl.c: fix mem leak in aac_send_raw_srb()

We leak in drivers/scsi/aacraid/commctrl.c::aac_send_raw_srb() :

We allocate memory:
        ...
                        struct user_sgmap* usg;
                        usg = kmalloc(actual_fibsize - sizeof(struct aac_srb)
                          + sizeof(struct sgmap), GFP_KERNEL);
and then neglect to free it:
        ...
                        for (i = 0; i < usg->count; i++) {
                                u64 addr;
                                void* p;
                                if (usg->sg[i].count >
                                    ((dev->adapter_info.options &
                                     AAC_OPT_NEW_COMM) ?
                                      (dev->scsi_host_ptr->max_sectors << 9) :
                                      65536)) {
                                        rcode = -EINVAL;
                                        goto cleanup;
        ... this 'goto' makes 'usg' go out of scope and leak the memory we
            allocated.
            Other exits properly kfree(usg), it's just here it is neglected.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/scsi/megaraid.c: fix sparse warnings
Randy Dunlap [Mon, 24 Oct 2011 14:53:48 +0000 (01:53 +1100)]
drivers/scsi/megaraid.c: fix sparse warnings

Fix sparse warnings of right shift bigger than source value size:

drivers/scsi/megaraid.c:311:65: warning: right shift by bigger than source value
drivers/scsi/megaraid.c:313:65: warning: right shift by bigger than source value
drivers/scsi/megaraid.c:317:67: warning: right shift by bigger than source value
drivers/scsi/megaraid.c:319:67: warning: right shift by bigger than source value

Patch suggestion from email by Al Viro:

"Since both are claimed to be strings, I really suspect that this >> 8 is
misspelled >> 4 and they have a character followed by pair of two-digit
packed decimals in there..."

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Neela Syam Kolli <megaraidlinux@lsi.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoscsi: fix a header to include linux/types.h
Alexander Shishkin [Mon, 24 Oct 2011 14:53:47 +0000 (01:53 +1100)]
scsi: fix a header to include linux/types.h

For headers that get exported to userland and make use of u32 style
type names, it is advised to include linux/types.h.

This fixes a headers_check warning.

Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/firmware/dmi_scan.c: make dmi_name_in_vendors more focused
Jean Delvare [Mon, 24 Oct 2011 14:53:47 +0000 (01:53 +1100)]
drivers/firmware/dmi_scan.c: make dmi_name_in_vendors more focused

The current implementation of dmi_name_in_vendors() is an invitation to
lazy coding and false positives [1].  Searching for a string in 8 know
what you're looking for, so you should know where to look.  strstr isn't
fast, especially when it fails, so we should avoid calling it when it just
can't succeed.

Looking at the current users of the function, it seems clear to me that
they are looking for a system or board vendor name, so let's limit
dmi_name_in_vendors to these two DMI fields.  This much better matches the
function name, BTW.

[1] We currently have code looking for short names in DMI data, such
as "IBM", "ASUS" or "Acer". I let you guess what will happen the day
other vendors ship products named, for example, "SCHREIBMEISTER",
"PEGASUS" or "Acerola".

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoparisc, exec: remove redundant set_fs(USER_DS)
Mathias Krause [Mon, 24 Oct 2011 14:53:46 +0000 (01:53 +1100)]
parisc, exec: remove redundant set_fs(USER_DS)

The address limit is already set in flush_old_exec() so those calls to
set_fs(USER_DS) are redundant.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoocfs2: avoid unaligned access to dqc_bitmap
Akinobu Mita [Mon, 24 Oct 2011 14:53:46 +0000 (01:53 +1100)]
ocfs2: avoid unaligned access to dqc_bitmap

The dqc_bitmap field of struct ocfs2_local_disk_chunk is 32-bit aligned,
but not 64-bit aligned.  The dqc_bitmap is accessed by ocfs2_set_bit(),
ocfs2_clear_bit(), ocfs2_test_bit(), or ocfs2_find_next_zero_bit().  These
are wrapper macros for ext2_*_bit() which need to take an unsigned long
aligned address (though some architectures are able to handle unaligned
address correctly)

So some 64bit architectures may not be able to access the dqc_bitmap
correctly.

This avoids such unaligned access by using another wrapper functions for
ext2_*_bit().  The code is taken from fs/ext4/mballoc.c which also need to
handle unaligned bitmap access.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoext4: use proper little-endian bitops
Akinobu Mita [Mon, 24 Oct 2011 14:53:46 +0000 (01:53 +1100)]
ext4: use proper little-endian bitops

ext4_{set,clear}_bit() is defined as __test_and_{set,clear}_bit_le() for
ext4.  Only two ext4_{set,clear}_bit() calls check the return value.  The
rest of calls ignore the return value and they can be replaced with
__{set,clear}_bit_le().

This changes ext4_{set,clear}_bit() from __test_and_{set,clear}_bit_le()
to __{set,clear}_bit_le() and introduces ext4_test_and_{set,clear}_bit()
for the two places where old bit needs to be returned.

This ext4_{set,clear}_bit() change is considered safe, because if someone
uses these macros without noticing the change, new ext4_{set,clear}_bit
don't have return value and causes compiler errors where the return value
is used.

This also removes unused ext4_find_first_zero_bit().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agokernel/timer.c: use debugobjects to catch deletion of uninitialized timers
Christine Chan [Mon, 24 Oct 2011 14:53:45 +0000 (01:53 +1100)]
kernel/timer.c: use debugobjects to catch deletion of uninitialized timers

del_timer_sync() calls debug_object_assert_init() to assert that a timer
has been initialized before calling lock_timer_base().  lock_timer_base()
would spin forever on a NULL(uninit-ed) base.  The check is added to
del_timer() to prevent silent failure, even though it would not get stuck
in an infinite loop.

Signed-off-by: Christine Chan <cschan@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodebugobjects: extend debugobjects to assert that an object is initialized
Christine Chan [Mon, 24 Oct 2011 14:53:45 +0000 (01:53 +1100)]
debugobjects: extend debugobjects to assert that an object is initialized

Add new check (assert_init) to make sure objects are initialized and
tracked by debugobjects.

Signed-off-by: Christine Chan <cschan@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h: remove unused macro pr_fmt()
Andrew Morton [Mon, 24 Oct 2011 14:53:45 +0000 (01:53 +1100)]
drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h: remove unused macro pr_fmt()

In file included from drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c:22:
drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h:24:1: warning: "pr_fmt" redefined
In file included from include/linux/kernel.h:20,
                 from include/linux/cache.h:4,
                 from include/linux/time.h:7,
                 from include/linux/stat.h:60,
                 from include/linux/module.h:10,
                 from drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c:21:
include/linux/printk.h:152:1: warning: this is the location of the previous definition

Cc: Tomoya <tomoya-linux@dsn.okisemi.com>
Cc: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agounicore32, exec: remove redundant set_fs(USER_DS)
Mathias Krause [Mon, 24 Oct 2011 14:53:44 +0000 (01:53 +1100)]
unicore32, exec: remove redundant set_fs(USER_DS)

The address limit is already set in flush_old_exec() so this
set_fs(USER_DS) is redundant.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoipc-mqueue-update-maximums-for-the-mqueue-subsystem-checkpatch-fixes
Andrew Morton [Mon, 24 Oct 2011 14:53:44 +0000 (01:53 +1100)]
ipc-mqueue-update-maximums-for-the-mqueue-subsystem-checkpatch-fixes

Cc: Amerigo Wang <amwang@redhat.com>
ERROR: Macros with complex values should be enclosed in parenthesis
#87: FILE: include/linux/ipc_namespace.h:126:
+#define DFLT_MSGSIZEMAX 1024*1024

ERROR: Macros with complex values should be enclosed in parenthesis
#88: FILE: include/linux/ipc_namespace.h:127:
+#define HARD_MSGSIZEMAX      16*1024*1024

total: 2 errors, 0 warnings, 75 lines checked

./patches/ipc-mqueue-update-maximums-for-the-mqueue-subsystem.patch has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Doug Ledford <dledford@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoipc-mqueue-update-maximums-for-the-mqueue-subsystem-fix
Stephen Rothwell [Mon, 24 Oct 2011 14:53:44 +0000 (01:53 +1100)]
ipc-mqueue-update-maximums-for-the-mqueue-subsystem-fix

ipc/mqueue.c: In function 'mqueue_get_inode':
ipc/mqueue.c:154:4: error: implicit declaration of function 'vmalloc'
ipc/mqueue.c:154:19: warning: assignment makes pointer from integer without=
 a cast
ipc/mqueue.c: In function 'mqueue_evict_inode':
ipc/mqueue.c:278:3: error: implicit declaration of function 'vfree'

Caused by commit 8a53f9442429 ("ipc/mqueue: update maximums for the
mqueue subsystem").  See Rule 1 in Documentation/SubmitChecklist.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Doug Ledford <dledford@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoipc/mqueue: update maximums for the mqueue subsystem
Doug Ledford [Mon, 24 Oct 2011 14:53:43 +0000 (01:53 +1100)]
ipc/mqueue: update maximums for the mqueue subsystem

Commit b231cca4381ee ("message queues: increase range limits") changed the
maximum size of a message in a message queue from INT_MAX to 8192*128.
Unfortunately, we had customers that relied on a size much larger than
8192*128 on their production systems.  After reviewing POSIX, we found
that it is silent on the maximum message size.  We did find a couple other
areas in which it was not silent.  Fix up the mqueue maximums so that the
customer's system can continue to work, and document both the POSIX and
real world requirements in ipc_namespace.h so that we don't have this
issue crop back up.

Also, commit 9cf18e1dd74c ("ipc: HARD_MSGMAX should be higher not lower on
64bit") fiddled with HARD_MSGMAX without realizing that the number was
intentionally in place to limit the msg queue depth to one that was small
enough to kmalloc an array of pointers (hence why we divided 128k by
sizeof(long)).  If we wish to meet POSIX requirements, we have no choice
but to change our allocation to a vmalloc instead (at least for the large
queue size case).  With that, it's possible to increase our allowed
maximum to the POSIX requirements (or more if we choose).

Signed-off-by: Doug Ledford <dledford@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Joe Korty <joe.korty@ccur.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoipc/mqueue: enforce hard limits
Doug Ledford [Mon, 24 Oct 2011 14:53:43 +0000 (01:53 +1100)]
ipc/mqueue: enforce hard limits

In two places we don't enforce the hard limits for CAP_SYS_RESOURCE apps.
In preparation for making more reasonable hard limits, start enforcing
them even on CAP_SYS_RESOURCE.

Signed-off-by: Doug Ledford <dledford@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Joe Korty <joe.korty@ccur.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoipc/mqueue: switch back to using non-max values on create
Doug Ledford [Mon, 24 Oct 2011 14:53:42 +0000 (01:53 +1100)]
ipc/mqueue: switch back to using non-max values on create

Commit b231cca4381ee15e ("message queues: increase range limits") changed
how we create a queue that does not include an attr struct passed to open
so that it creates the queue with whatever the maximum values are.
However, if the admin has set the maximums to allow flexibility in
creating a queue (aka, both a large size and large queue are allowed, but
combined they create a queue too large for the RLIMIT_MSGQUEUE of the
user), then attempts to create a queue without an attr struct will fail.
Switch back to using acceptable defaults regardless of what the maximums
are.

Signed-off-by: Doug Ledford <dledford@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Joe Korty <joe.korty@ccur.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoipc/mqueue: cleanup definition names and locations
Doug Ledford [Mon, 24 Oct 2011 14:53:42 +0000 (01:53 +1100)]
ipc/mqueue: cleanup definition names and locations

We had a customer come up with a problem while trying to upgrade from our
2.6.18 kernel to our 2.6.32 kernel.  In diagnosing their problem, it was
determined that when commit b231cca4 ("message queues: increase range
limits") changed the msg size max from INT_MAX to 8192*128, that's what
broke their setup.

While fixing this problem, testing showed that if you increase the max
values of a msg queue, then attempt to create one without an attr struct
passed in to the open call, it could fail because it sets the queue size
to the max of both the msg size and queue size.  If these are large
enough, they over run the default RLIMIT_MSGQUEUE.  This change was also
introduced in the b231cca4 ("message queues: increase range limits")
commit.

We then found that the msg queue limits were not all being enforced on
CAP_SYS_RESOURCE apps.

Finally, we found that commit 9cf18e1d ("ipc: HARD_MSGMAX should be higher
not lower on 64bit") fiddled with HARD_MSGMAX without realizing that the
reason it was set to what it was, was to avoid trying to kmalloc a chunk
larger than 128K.

So this series of patches cleans up the various defines, takes us back to
having a larger HARD_MSGSIZEMAX, goes back to using a separate define for
the case where a user doesn't pass in an attr struct in case the maxes
have been raised too large for RLIMIT_MSGQUEUE, enforces the maximums on
CAP_SYS_RESOURCE apps, uses vmalloc instead of kmalloc when the msg
pointer array is too large, and documents all of this so it shouldn't
happen again.

This patch:

The various defines for minimums and maximums of the sysctl controllable
mqueue values are scattered amongst different files and named
inconsistently.  Move them all into ipc_namespace.h and make them have
consistent names.  Additionally, make the number of queues per namespace
also have a minimum and maximum and use the same sysctl function as the
other two settable variables.

Signed-off-by: Doug Ledford <dledford@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Joe Korty <joe.korty@ccur.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agobrlocks-lglocks-clean-up-code-checkpatch-fixes
Andrew Morton [Mon, 24 Oct 2011 14:53:41 +0000 (01:53 +1100)]
brlocks-lglocks-clean-up-code-checkpatch-fixes

Cc: Al Viro <viro@zeniv.linux.org.uk>
ERROR: trailing whitespace
#768: FILE: include/linux/lglock.h:54:
+#endif $

WARNING: line over 80 characters
#772: FILE: include/linux/lglock.h:58:
+ DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) = __ARCH_SPIN_LOCK_UNLOCKED; \

ERROR: trailing whitespace
#917: FILE: kernel/lglock.c:5:
+void lg_lock_init(struct lglock *lg, char *name) $

ERROR: trailing whitespace
#923: FILE: kernel/lglock.c:11:
+void lg_local_lock(struct lglock *lg) $

ERROR: trailing whitespace
#933: FILE: kernel/lglock.c:21:
+void lg_local_unlock(struct lglock *lg) $

ERROR: trailing whitespace
#943: FILE: kernel/lglock.c:31:
+void lg_local_lock_cpu(struct lglock *lg, int cpu) $

ERROR: trailing whitespace
#953: FILE: kernel/lglock.c:41:
+void lg_local_unlock_cpu(struct lglock *lg, int cpu) $

ERROR: trailing whitespace
#963: FILE: kernel/lglock.c:51:
+void lg_global_lock_online(struct lglock *lg) $

total: 7 errors, 1 warnings, 893 lines checked

NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or
      scripts/cleanfile

./patches/brlocks-lglocks-clean-up-code.patch has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agobrlocks/lglocks: clean up code
Andi Kleen [Mon, 24 Oct 2011 14:53:41 +0000 (01:53 +1100)]
brlocks/lglocks: clean up code

lglocks and brlocks are currently generated with some complicated macros
in lglock.h.  But there's no reason I can see to not just use common
utility functions that get pointers to the lglock.

Since there are at least two users it makes sense to share this code in a
library.

This will also make it later possible to dynamically allocate lglocks.

In general the users now look more like normal function calls with
pointers, not magic macros.

The patch is rather large because I move over all users in one go to keep
it bisectable.  This impacts the VFS somewhat in terms of lines changed.
But no actual behaviour change.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoia64, exec: remove redundant set_fs(USER_DS)
Mathias Krause [Mon, 24 Oct 2011 14:53:41 +0000 (01:53 +1100)]
ia64, exec: remove redundant set_fs(USER_DS)

The address limit is already set in flush_old_exec() so this
set_fs(USER_DS) is redundant.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agohrtimers: Special-case zero length sleeps
Matthew Garrett [Mon, 24 Oct 2011 14:53:40 +0000 (01:53 +1100)]
hrtimers: Special-case zero length sleeps

sleep(0) is a common construct used by applications that want to trigger
the scheduler.  sched_yield() might make more sense, but only appeared in
POSIX.1-2001 and so plenty of example code still uses the sleep(0) form.

This wouldn't normally be a problem, but it means that event-driven
applications that are merely trying to avoid starving other processes may
actually end up sleeping due to having large timer_slack values.  Special-
casing this seems reasonable.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrm: avoid switching to text console if there is no panic timeout
Hugh Dickins [Mon, 24 Oct 2011 14:53:40 +0000 (01:53 +1100)]
drm: avoid switching to text console if there is no panic timeout

Add a check for panic_timeout in the drm_fb_helper_panic() notifier: if
we're going to reboot immediately, the user will not be able to see the
messages anyway, and messing with the video mode may display artifacts,
and certainly get into several layers of complexity (including mutexes and
memory allocations) which we shall be much safer to avoid.

[msb@chromium.org: edited commit message and modified to short-circuit panic_timeout < 0 instead of testing panic_timeout >= 0]
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Dave Airlie <airlied@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Stéphane Marchesin <marcheu@chromium.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/gpu/vga/vgaarb.c: add missing kfree
Julia Lawall [Mon, 24 Oct 2011 14:53:39 +0000 (01:53 +1100)]
drivers/gpu/vga/vgaarb.c: add missing kfree

kbuf is a buffer that is local to this function, so all of the error paths
leaving the function should release it.

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodevtmpfsd: fix task state handling
Kautuk Consul [Mon, 24 Oct 2011 14:53:39 +0000 (01:53 +1100)]
devtmpfsd: fix task state handling

- Set the state to TASK_INTERRUPTIBLE using __set_current_state()
  instead of set_current_state() as the spin_unlock is an implicit memory
  barrier.

- After return from schedule(), there is no need to set the current
  state to TASK_RUNNING - a call to schedule() always returns in
  TASK_RUNNING state.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/edac/mpc85xx_edac.c: fix memory controller compatible for edac
Shaohui Xie [Mon, 24 Oct 2011 14:53:38 +0000 (01:53 +1100)]
drivers/edac/mpc85xx_edac.c: fix memory controller compatible for edac

compatible in dts has been changed, so the driver needs to be updated
accordingly.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoceph/mds_client.c: quiet sparse noise
H Hartley Sweeten [Mon, 24 Oct 2011 14:53:37 +0000 (01:53 +1100)]
ceph/mds_client.c: quiet sparse noise

warning: symbol 'get_nonsnap_parent' was not declared. Should it be static?
warning: symbol 'done_closing_sessions' was not declared. Should it be static?

Local functions don't need external visability. Make them static.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Sage Weil <sage@newdream.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agobtrfs: don't dereference extent_mapping if NULL
Roel Kluin [Mon, 24 Oct 2011 14:53:36 +0000 (01:53 +1100)]
btrfs: don't dereference extent_mapping if NULL

Don't dereference em if it's NULL or an error pointer.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoaudit: always follow va_copy() with va_end()
Jesper Juhl [Mon, 24 Oct 2011 14:53:36 +0000 (01:53 +1100)]
audit: always follow va_copy() with va_end()

A call to va_copy() should always be followed by a call to va_end() in the
same function.  In kernel/autit.c::audit_log_vformat() this is not always
done.  This patch makes sure va_end() is always called.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoarm, exec: remove redundant set_fs(USER_DS)
Mathias Krause [Mon, 24 Oct 2011 14:53:35 +0000 (01:53 +1100)]
arm, exec: remove redundant set_fs(USER_DS)

The address limit is already set in flush_old_exec() so this
set_fs(USER_DS) is redundant.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoarch/arm/mach-ux500/mbox-db5500.c: world-writable sysfs fifo file
Vasiliy Kulikov [Mon, 24 Oct 2011 14:53:35 +0000 (01:53 +1100)]
arch/arm/mach-ux500/mbox-db5500.c: world-writable sysfs fifo file

Don't allow everybody to use a modem.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agox86-reduce-clock-calibration-time-during-slave-cpu-startup-fix
Andrew Morton [Mon, 24 Oct 2011 14:53:35 +0000 (01:53 +1100)]
x86-reduce-clock-calibration-time-during-slave-cpu-startup-fix

fix CONFIG_SMP=n build

arch/x86/kernel/tsc.c: In function 'calibrate_delay_is_known':
arch/x86/kernel/tsc.c:1012: error: 'struct cpuinfo_x86' has no member named 'phys_proc_id'
arch/x86/kernel/tsc.c:1012: error: 'struct cpuinfo_x86' has no member named 'phys_proc_id'
arch/x86/kernel/tsc.c:1006: warning: unused variable 'cpu'

Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agox86: reduce clock calibration time during slave cpu startup
Jack Steiner [Mon, 24 Oct 2011 14:53:34 +0000 (01:53 +1100)]
x86: reduce clock calibration time during slave cpu startup

Reduce the startup time for slave cpus.

Adds hooks for an arch-specific function for clock calibration.  These
hooks are used on x86.  If a newly started cpu has the same phys_proc_id
as a core already active, uses the TSC for the delay loop and has a
CONSTANT_TSC, use the already-calculated value of loops_per_jiffy.

This patch reduces the time required to start slave cpus on a 4096 cpu
system from: 465 sec OLD 62 sec NEW

This reduces boot time on a 4096p system by almost 7 minutes.  Nice...

Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agox86: tlb flush avoid superflous leave_mm()
Shaohua Li [Mon, 24 Oct 2011 14:53:34 +0000 (01:53 +1100)]
x86: tlb flush avoid superflous leave_mm()

If just one page VA tlb is required to be flushed and current task is in
lazy TLB state, doing leave_mm() is superfluous because it flushes the
whole TLB.  This can reduce some TLB miss.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoarch/x86/mm/pageattr.c: quiet sparse noise; local functions should be static
H Hartley Sweeten [Mon, 24 Oct 2011 14:53:33 +0000 (01:53 +1100)]
arch/x86/mm/pageattr.c: quiet sparse noise; local functions should be static

Local functions should be marked static.  This quiets the following
sparse noise:

warning: symbol '_set_memory_array' was not declared. Should it be static?

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoarch/x86/kernel/ptrace.c: quiet sparse noise
H Hartley Sweeten [Mon, 24 Oct 2011 14:53:33 +0000 (01:53 +1100)]
arch/x86/kernel/ptrace.c: quiet sparse noise

ptrace_set_debugreg() is only used in this file and should be static.
This quiets the following sparse warning:

warning: symbol 'ptrace_set_debugreg' was not declared. Should it be static?

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agoarch/x86/kernel/e820.c: quiet sparse noise about plain integer as NULL pointer
H Hartley Sweeten [Mon, 24 Oct 2011 14:53:33 +0000 (01:53 +1100)]
arch/x86/kernel/e820.c: quiet sparse noise about plain integer as NULL pointer

The last parameter to sort() is a pointer to the function used to swap
items.  This parameter should be NULL, not 0, when not used.  This quiets
the following sparse warning:

warning: Using plain integer as NULL pointer

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agox86,mrst: add mapping for bma023
William Douglas [Mon, 24 Oct 2011 14:53:32 +0000 (01:53 +1100)]
x86,mrst: add mapping for bma023

There is now an upstream bma023 driver so instead of submitting ours we
use that one.  The defaults are just fine so it's a simple mapping entry.

(Thanks go to Erik Andersson for incorporating the changes we needed into his
 version)

Signed-off-by: William Douglas <william.douglas@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
12 years agodrivers/power/intel_mid_battery.c: fix build
Andrew Morton [Mon, 24 Oct 2011 14:53:32 +0000 (01:53 +1100)]
drivers/power/intel_mid_battery.c: fix build

Seems that nobody's even trying any more.

Cc: Nithish Mahalingam <nithish.mahalingam@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Major Lee <major_lee@wistron.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>