Recently, Robert Mueller reported (http://lkml.org/lkml/2010/9/12/236)
that zone_reclaim_mode doesn't work properly on his new NUMA server (Dual
Xeon E5520 + Intel S5520UR MB).  He is using Cyrus IMAPd and it's built on
a very traditional single-process model.

  * a master process which reads config files and manages the other
    process
  * multiple imapd processes, one per connection
  * multiple pop3d processes, one per connection
  * multiple lmtpd processes, one per connection
  * periodical "cleanup" processes.

There are thousands of independent processes.  The problem is, recent
Intel motherboard turn on zone_reclaim_mode by default and traditional
prefork model software don't work well on it.  Unfortunatelly, such models
are still typical even in the 21st century.  We can't ignore them.

This patch raises the zone_reclaim_mode threshold to 30.  30 doesn't have
any specific meaning.  but 20 means that one-hop QPI/Hypertransport and
such relatively cheap 2-4 socket machine are often used for traditional
servers as above.  The intention is that these machines don't use
zone_reclaim_mode.

Note: ia64 and Power have arch specific RECLAIM_DISTANCE definitions.
This patch doesn't change such high-end NUMA machine behavior.

Dave Hansen said:

: I know specifically of pieces of x86 hardware that set the information
: in the BIOS to '21' *specifically* so they'll get the zone_reclaim_mode
: behavior which that implies.
:
: They've done performance testing and run very large and scary benchmarks
: to make sure that they _want_ this turned on.  What this means for them
: is that they'll probably be de-optimized, at least on newer versions of
: the kernel.
:
: If you want to do this for particular systems, maybe _that_'s what we
: should do.  Have a list of specific configurations that need the
: defaults overridden either because they're buggy, or they have an
: unusual hardware configuration not really reflected in the distance
: table.

And later said:

: The original change in the hardware tables was for the benefit of a
: benchmark.  Said benchmark isn't going to get run on mainline until the
: next batch of enterprise distros drops, at which point the hardware where
: this was done will be irrelevant for the benchmark.  I'm sure any new
: hardware will just set this distance to another yet arbitrary value to
: make the kernel do what it wants.  :)
:
: Also, when the hardware got _set_ to this initially, I complained.  So, I
: guess I'm getting my way now, with this patch.  I'm cool with it.
Reported-by: Robert Mueller <robm@fastmail.fm>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Warn about uses of printk_ratelimit() because it uses a global state and
can hide subsequent useful messages.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix <linux/kmsg_dump.h> when CONFIG_PRINTK is not enabled:

  include/linux/kmsg_dump.h:56: error: 'EINVAL' undeclared (first use in this function)
  include/linux/kmsg_dump.h:61: error: 'EINVAL' undeclared (first use in this function)

Looks like commit 595dd3d8 ("kmsg_dump: fix build for
CONFIG_PRINTK=n") uses EINVAL without having the needed header file(s),
but I'm sure that I build tested that patch also.  oh well.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[akpm@linux-foundation.org: rework text, fit it into 80-cols]
Signed-off-by: Ying Han <yinghan@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

While testing for memcg aware swap token, I observed a swap token was
often grabbed an intermittent running process (eg init, auditd) and they
never release a token.

Why?

Some processes (eg init, auditd, audispd) wake up when a process exiting.
And swap token can be get first page-in process when a process exiting
makes no swap token owner.  Thus such above intermittent running process
often get a token.

And currently, swap token priority is only decreased at page fault path.
Then, if the process sleep immediately after to grab swap token, the swap
token priority never be decreased.  That's obviously undesirable.

This patch implement very poor (and lightweight) priority aging.  It only
be affect to the above corner case and doesn't change swap tendency
workload performance (eg multi process qsbench load)
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is useful for observing swap token activity.

example output:

             zsh-1845  [000]   598.962716: update_swap_token_priority:
mm=ffff88015eaf7700 old_prio=1 new_prio=0
          memtoy-1830  [001]   602.033900: update_swap_token_priority:
mm=ffff880037a45880 old_prio=947 new_prio=949
          memtoy-1830  [000]   602.041509: update_swap_token_priority:
mm=ffff880037a45880 old_prio=949 new_prio=951
          memtoy-1830  [000]   602.051959: update_swap_token_priority:
mm=ffff880037a45880 old_prio=951 new_prio=953
          memtoy-1830  [000]   602.052188: update_swap_token_priority:
mm=ffff880037a45880 old_prio=953 new_prio=955
          memtoy-1830  [001]   602.427184: put_swap_token:
token_mm=ffff880037a45880
             zsh-1789  [000]   602.427281: replace_swap_token:
old_token_mm=          (null) old_prio=0 new_token_mm=ffff88015eaf7018
new_prio=2
             zsh-1789  [001]   602.433456: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=2 new_prio=4
             zsh-1789  [000]   602.437613: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=4 new_prio=6
             zsh-1789  [000]   602.443924: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=6 new_prio=8
             zsh-1789  [000]   602.451873: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=8 new_prio=10
             zsh-1789  [001]   602.462639: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=10 new_prio=12
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Rik van Riel<riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently, memcg reclaim can disable swap token even if the swap token mm
doesn't belong in its memory cgroup.  It's slightly risky.  If an admin
creates very small mem-cgroup and silly guy runs contentious heavy memory
pressure workload, every tasks are going to lose swap token and then
system may become unresponsive.  That's bad.

This patch adds 'memcg' parameter into disable_swap_token().  and if the
parameter doesn't match swap token, VM doesn't disable it.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit a8bef8ff ("mm: migration: avoid race between shift_arg_pages()
and rmap_walk() during migration by not migrating temporary stacks")
introduced a BUG_ON() to ensure that VM_STACK_FLAGS and
VM_STACK_INCOMPLETE_SETUP do not overlap.  The check is a compile time
one, so BUILD_BUG_ON is more appropriate.
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new kernel-doc warnings in lib/bitmap.c:

  Warning(lib/bitmap.c:596): No description found for parameter 'buf'
  Warning(lib/bitmap.c:596): Excess function parameter 'bp' description in '__bitmap_parselist'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new kernel-doc warnings in mm/memory.c:

  Warning(mm/memory.c:1327): No description found for parameter 'tlb'
  Warning(mm/memory.c:1327): Excess function parameter 'tlbp' description in 'unmap_vmas'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Johannes noticed the vmstat update is already taken care of by
khugepaged_alloc_hugepage() internally.  The only places that are required
to update the vmstat are the callers of alloc_hugepage (callers of
khugepaged_alloc_hugepage aren't).
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Johannes Weiner <jweiner@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc warnings in signal.c:

  Warning(kernel/signal.c:2374): No description found for parameter 'nset'
  Warning(kernel/signal.c:2374): Excess function parameter 'set' description in 'sys_rt_sigprocmask'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[ Also from Ben Hutchings <ben@decadent.org.uk> and Vitaliy Ivanov
  <vitalivanov@gmail.com> ]

Commit 06ae40ce ("x86 idle: EXPORT_SYMBOL(default_idle, pm_idle)
only when APM demands it") removed the export for pm_idle/default_idle
unless the apm module was modularised and CONFIG_APM_CPU_IDLE was set.

But the apm module uses pm_idle/default_idle unconditionally,
CONFIG_APM_CPU_IDLE only affects the bios idle threshold.  Adjust the
export accordingly.

[ Used #ifdef instead of #if defined() as it's shorter, and what both
  Ben and Vitaliy used.. Andy, you're out-voted ;)    - Linus ]
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: use kernel processor defines for conditional optimizations
  m68knommu: create config options for CPU classes
  m68knommu: fix linker script exported name sections

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  TOMOYO: Fix oops in tomoyo_mount_acl().

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/avr32-2.6:
  avr32, exec: remove redundant set_fs(USER_DS)
  avr32: make intc_resume() return void to conform to syscore_ops
  avr32: add some more at91 to cpu.h definition
  avr32: set CONFIG_CC_OPTIMIZE_FOR_SIZE=y for all defconfigs
  avr32/at32ap: fix mapping of platform device id for USART
  avr32: fix use of non-existing portnr variable in at32_map_usart()

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm: Compare only lower 32 bits of framebuffer map offsets
  drm/i915: Don't leak in i915_gem_shmem_pread_slow()
  drm/radeon/kms: do bounds checking for 3D_LOAD_VBPNTR and bump array limit
  drm/radeon/kms: fix mac g5 quirk
  x86/uv/x2apic: update for change in pci bridge handling.
  alpha, drm: Remove obsolete Alpha support in MGA DRM code
  alpha/drm: Cleanup Alpha support in DRM generic code
  savage: remove unnecessary if statement
  drm/radeon: fix GUI idle IH debug statements
  drm/radeon/kms: check modes against max pixel clock
  drm: fix fbs in DRM_IOCTL_MODE_GETRESOURCES ioctl

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  [CIFS] update cifs version to 1.73
  [CIFS] trivial cleanup fscache cFYI and cERROR messages
  cifs: correctly handle NULL tcon pointer in CIFSTCon
  cifs: show sec= option in /proc/mounts
  cifs: don't allow cifs_reconnect to exit with NULL socket pointer
  CIFS: Fix sparse error

* 'for-linus' of git://neil.brown.name/md:
  md/raid5: remove unusual use of bio_iovec_idx()
  md/raid5: fix FUA request handling in ops_run_io()
  md/raid5: fix raid5_set_bi_hw_segments
  md:Documentation/md.txt - fix typo
  md/bitmap: remove unused fields from struct bitmap
  md/bitmap: use proper accessor macro
  md: check ->hot_remove_disk when removing disk
  md: Using poll  /proc/mdstat can monitor the events of adding a spare disks
  MD: use is_power_of_2 macro
  MD: raid5 do not set fullsync
  MD: support initial bitmap creation in-kernel
  MD: add sync_super to mddev_t struct
  MD: raid1 changes to allow use by device mapper
  MD: move thread wakeups into resume
  MD: possible typo
  MD: no sync IO while suspended
  MD: no integrity register if no gendisk

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Remove cpufreq_stats sysfs entries on module unload.
  MAINTAINERS: Update CPU FREQUENCY patterns

Signed-off-by: Steve French <sfrench@us.ibm.com>

... for uniformity and cleaner debug logs.
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>

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>
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

This patch removes the unneeded, and now wrong, return 0 from intc_resume() and
lets the function return void instead. This matches the resume callback in
struct syscore_ops.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

Somme common drivers will need those at91 cpu_is_xxx() definitions.
Those definitions are already in Linus' tree so if we want to use them
in common drivers, we will need them in AVR32 cpu.h file.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

This patch makes sure the kconfig option CC_OPTIMIZE_FOR_SIZE is set to yes for
all default configuration files. This ensures the kernel is optimized for size,
and avoids potential relocation truncated to fit problems.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

This patch will fix the mapping of the platform device id when mapping USART
peripheral ID to UART platform device id. Not setting the platform device id
will in most cases (when you map USART > 0 to UART 0) make the console not
available.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

This patch fixes the use of the non-existing portnr variable in
at32_map_usart() to use the provided line number instead. Typo was introduced
in commit 2b348e2f.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>

In tomoyo_mount_acl() since 2.6.36, kern_path() was called without checking
dev_name != NULL. As a result, an unprivileged user can trigger oops by issuing
mount(NULL, "/", "ext3", 0, NULL) request.
Fix this by checking dev_name != NULL before calling kern_path(dev_name).
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>

In the bio_for_each_segment loop, bvl always points current
bio_vec, so the same as bio_iovec_idx(, i). Let's get rid of
it.

Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

Commit e9c7469b ("md: implment REQ_FLUSH/FUA support")
introduced R5_WantFUA flag and set rw to WRITE_FUA in that case.
However remaining code still checks whether rw is exactly same
as WRITE or not, so FUAed-write ends up with being treated as
READ. Fix it.

This bug has been present since 2.6.37 and the fix is suitable for any
-stable kernel since then.  It is not clear why this has not caused
more problems.

Cc: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

The @bio->bi_phys_segments consists of active stripes count in the
lower 16 bits and processed stripes count in the upper 16 bits. So
logical-OR operator should be bitwise one.

This bug has been present since 2.6.27 and the fix is suitable for any
-stable kernel since then.  Fortunately the bad code is only used on
error paths and is relatively unlikely to be hit.

Cc: stable@kernel.org
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

Older m68k-linux compilers will include pre-defined symbols that
confuse what processor it is being targeted for. For example gcc-4.1.2
will pre-define __mc68020__ even if you specify the target processor
as -m68000 on the gcc command line. Newer versions of gcc have this
corrected.

In a few places the m68k code uses defined(__mc68020__) for optimizations
that include instructions that are specific to the CPU 68020 and above.
When compiling with older compilers this will be true even when we have
selected to compile for the older 68000 processors.

Switch to using the kernel processor defines, CONFIG_M68020 and friends.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>

There are 3 families of CPU core types that we support in the m68knommu
architecture branch. They are

. traditional 68000
. CPU32 (a 68020 core derivative without MMU or bitfield instructions)
. ColdFire

It will be useful going forward to have a CONFIG_ option defined for
each type. We already have one for ColdFire (CONFIG_COLDFIRE), so add
for the other 2 families, CONFIG_M68000 and CONFIG_MCPU32.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>

The recent commit titled "module: Sort exported symbols" (f02e8a65)
changed the exported symbol name sections. Bring the m68knommu linker
script into line with those changes - including the sorting of the
symbol names.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>

Drivers using multiple framebuffers got broken by commit
41c2e75e which ignored the framebuffer
(or register) map offset when looking for existing maps. The rationale
was that the kernel-userspace ABI is fixed at a 32-bit offset, so the
real offsets could not always be handed over for comparison.

Instead of ignoring the offset we will compare the lower 32 bit. Drivers
using multiple framebuffers should just make sure that the lower 32 bit
are different. The existing drivers in question are practically limited
to 32-bit systems so that should be fine for them.

It is assumed that current drivers always specify a correct framebuffer
map offset, even if this offset was ignored since above commit. So this
patch should not change anything for drivers using only one framebuffer.

Drivers needing multiple framebuffers with 64-bit map offsets will need
to cook up something, for instance keeping an ID in the lower bit which
is to be aligned away when it comes to using the offset.

All of above applies to _DRM_REGISTERS as well.
Signed-off-by: Tormod Volden <debian.tormod@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

It seems to me that we are leaking 'user_pages' in
drivers/gpu/drm/i915/i915_gem.c::i915_gem_shmem_pread_slow() if
read_cache_page_gfp() fails.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>

To my knowledge, the limit is 16 on r300.
(the docs don't say what the limit is)

The lack of bounds checking can be abused to do all sorts of things
(from bypassing parts of the CS checker to crashing the kernel).

Bugzilla:
https://bugs.freedesktop.org/show_bug.cgi?id=36745

Cc: stable@kernel.org
Signed-off-by: Marek Olšák <maraeo@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>