Commit Graph

5620 Commits

Author SHA1 Message Date
Konstantin Khlebnikov
b413d48aa7 mm-tracepoint: rename page-free events
Rename mm_page_free_direct into mm_page_free and mm_pagevec_free into
mm_page_free_batched

Since v2.6.33-5426-gc475dab the kernel triggers mm_page_free_direct for
all freed pages, not only for directly freed.  So, let's name it properly.
 For pages freed via page-list we also trigger mm_page_free_batched event.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
Konstantin Khlebnikov
da066ad357 mm: remove unused pagevec_free
It not exported and now nobody uses it.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
Konstantin Khlebnikov
cc59850ef9 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>
Acked-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
Konstantin Khlebnikov
c909e99364 vmscan: activate executable pages after first usage
Logic added in commit 8cab4754d2 ("vmscan: make mapped executable pages
the first class citizen") was noticeably weakened in commit
6457474624 ("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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
Konstantin Khlebnikov
34dbc67a64 vmscan: promote shared file mapped pages
Commit 6457474624 ("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 bf3f3bc5e7 ("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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
Johannes Weiner
1edf223485 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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:41 -08:00
David Rientjes
74ee4ef1f9 slub: disallow changing cpu_partial from userspace for debug caches
For caches with debugging enabled, "slub: Switch per cpu partial page
support off for debugging" changes cpu_partial to 0.  It shouldn't be
tunable from userspace for such caches, otherwise the same accounting
issues arise during validation.

This patch disallows tuning /sys/kernel/slab/cache/cpu_partial to be non-
zero for caches with debugging enabled.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2012-01-10 21:31:09 +02:00
Linus Torvalds
38e5781bbf Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  igmp: Avoid zero delay when receiving odd mixture of IGMP queries
  netdev: make net_device_ops const
  bcm63xx: make ethtool_ops const
  usbnet: make ethtool_ops const
  net: Fix build with INET disabled.
  net: introduce netif_addr_lock_nested() and call if when appropriate
  net: correct lock name in dev_[uc/mc]_sync documentations.
  net: sk_update_clone is only used in net/core/sock.c
  8139cp: fix missing napi_gro_flush.
  pktgen: set correct max and min in pktgen_setup_inject()
  smsc911x: Unconditionally include linux/smscphy.h in smsc911x.h
  asix: fix infinite loop in rx_fixup()
  net: Default UDP and UNIX diag to 'n'.
  r6040: fix typo in use of MCR0 register bits
  net: fix sock_clone reference mismatch with tcp memcontrol
2012-01-09 14:46:52 -08:00
Steven Rostedt
4dee6b64ee tracing/mm: Move include of trace/events/kmem.h out of header into slab.c
Including trace/events/*.h TRACE_EVENT() macro headers in other headers
can cause strange side effects if another trace/event/*.h header
includes that header.  Having trace/events/kmem.h inside slab_def.h
caused a compile error in sparc64 when changes were done to some header
files.  Moving the kmem.h trace header out of slab.h and into slab.c
fixes the problem.

Note, both slub.c and slob.c already include the trace/events/kmem.h
file. Only slab.c had it missing.

Link: http://lkml.kernel.org/r/20120105190405.1e3191fb5a43b2a0f1655e1f@canb.auug.org.au

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-09 14:19:33 -08:00
Linus Torvalds
6b3da11b3c Merge branch 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: Remove irqsafe_cpu_xxx variants

Fix up conflict in arch/x86/include/asm/percpu.h due to clash with
cebef5beed ("x86: Fix and improve percpu_cmpxchg{8,16}b_double()")
which edited the (now removed) irqsafe_cpu_cmpxchg*_double code.
2012-01-09 13:08:28 -08:00
Linus Torvalds
db0c2bf69a Merge branch 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
* 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
  cgroup: fix to allow mounting a hierarchy by name
  cgroup: move assignement out of condition in cgroup_attach_proc()
  cgroup: Remove task_lock() from cgroup_post_fork()
  cgroup: add sparse annotation to cgroup_iter_start() and cgroup_iter_end()
  cgroup: mark cgroup_rmdir_waitq and cgroup_attach_proc() as static
  cgroup: only need to check oldcgrp==newgrp once
  cgroup: remove redundant get/put of task struct
  cgroup: remove redundant get/put of old css_set from migrate
  cgroup: Remove unnecessary task_lock before fetching css_set on migration
  cgroup: Drop task_lock(parent) on cgroup_fork()
  cgroups: remove redundant get/put of css_set from css_set_check_fetched()
  resource cgroups: remove bogus cast
  cgroup: kill subsys->can_attach_task(), pre_attach() and attach_task()
  cgroup, cpuset: don't use ss->pre_attach()
  cgroup: don't use subsys->can_attach_task() or ->attach_task()
  cgroup: introduce cgroup_taskset and use it in subsys->can_attach(), cancel_attach() and attach()
  cgroup: improve old cgroup handling in cgroup_attach_proc()
  cgroup: always lock threadgroup during migration
  threadgroup: extend threadgroup_lock() to cover exit and exec
  threadgroup: rename signal->threadgroup_fork_lock to ->group_rwsem
  ...

Fix up conflict in kernel/cgroup.c due to commit e0197aae59: "cgroups:
fix a css_set not found bug in cgroup_attach_proc" that already
mentioned that the bug is fixed (differently) in Tejun's cgroup
patchset. This one, in other words.
2012-01-09 12:59:24 -08:00
Linus Torvalds
98793265b4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (53 commits)
  Kconfig: acpi: Fix typo in comment.
  misc latin1 to utf8 conversions
  devres: Fix a typo in devm_kfree comment
  btrfs: free-space-cache.c: remove extra semicolon.
  fat: Spelling s/obsolate/obsolete/g
  SCSI, pmcraid: Fix spelling error in a pmcraid_err() call
  tools/power turbostat: update fields in manpage
  mac80211: drop spelling fix
  types.h: fix comment spelling for 'architectures'
  typo fixes: aera -> area, exntension -> extension
  devices.txt: Fix typo of 'VMware'.
  sis900: Fix enum typo 'sis900_rx_bufer_status'
  decompress_bunzip2: remove invalid vi modeline
  treewide: Fix comment and string typo 'bufer'
  hyper-v: Update MAINTAINERS
  treewide: Fix typos in various parts of the kernel, and fix some comments.
  clockevents: drop unknown Kconfig symbol GENERIC_CLOCKEVENTS_MIGR
  gpio: Kconfig: drop unknown symbol 'CS5535_GPIO'
  leds: Kconfig: Fix typo 'D2NET_V2'
  sound: Kconfig: drop unknown symbol ARCH_CLPS7500
  ...

Fix up trivial conflicts in arch/powerpc/platforms/40x/Kconfig (some new
kconfig additions, close to removed commented-out old ones)
2012-01-08 13:21:22 -08:00
Linus Torvalds
eb59c505f8 Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
  PM / Hibernate: Implement compat_ioctl for /dev/snapshot
  PM / Freezer: fix return value of freezable_schedule_timeout_killable()
  PM / shmobile: Allow the A4R domain to be turned off at run time
  PM / input / touchscreen: Make st1232 use device PM QoS constraints
  PM / QoS: Introduce dev_pm_qos_add_ancestor_request()
  PM / shmobile: Remove the stay_on flag from SH7372's PM domains
  PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume
  PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
  PM: Drop generic_subsys_pm_ops
  PM / Sleep: Remove forward-only callbacks from AMBA bus type
  PM / Sleep: Remove forward-only callbacks from platform bus type
  PM: Run the driver callback directly if the subsystem one is not there
  PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
  PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.
  PM / Sleep: Merge internal functions in generic_ops.c
  PM / Sleep: Simplify generic system suspend callbacks
  PM / Hibernate: Remove deprecated hibernation snapshot ioctls
  PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
  ARM: S3C64XX: Implement basic power domain support
  PM / shmobile: Use common always on power domain governor
  ...

Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused
XBT_FORCE_SLEEP bit
2012-01-08 13:10:57 -08:00
Linus Torvalds
972b2c7199 Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits)
  reiserfs: Properly display mount options in /proc/mounts
  vfs: prevent remount read-only if pending removes
  vfs: count unlinked inodes
  vfs: protect remounting superblock read-only
  vfs: keep list of mounts for each superblock
  vfs: switch ->show_options() to struct dentry *
  vfs: switch ->show_path() to struct dentry *
  vfs: switch ->show_devname() to struct dentry *
  vfs: switch ->show_stats to struct dentry *
  switch security_path_chmod() to struct path *
  vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
  vfs: trim includes a bit
  switch mnt_namespace ->root to struct mount
  vfs: take /proc/*/mounts and friends to fs/proc_namespace.c
  vfs: opencode mntget() mnt_set_mountpoint()
  vfs: spread struct mount - remaining argument of next_mnt()
  vfs: move fsnotify junk to struct mount
  vfs: move mnt_devname
  vfs: move mnt_list to struct mount
  vfs: switch pnode.h macros to struct mount *
  ...
2012-01-08 12:19:57 -08:00
Linus Torvalds
7affca3537 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
  arm: fix up some samsung merge sysdev conversion problems
  firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
  Drivers:hv: Fix a bug in vmbus_driver_unregister()
  driver core: remove __must_check from device_create_file
  debugfs: add missing #ifdef HAS_IOMEM
  arm: time.h: remove device.h #include
  driver-core: remove sysdev.h usage.
  clockevents: remove sysdev.h
  arm: convert sysdev_class to a regular subsystem
  arm: leds: convert sysdev_class to a regular subsystem
  kobject: remove kset_find_obj_hinted()
  m86k: gpio - convert sysdev_class to a regular subsystem
  mips: txx9_sram - convert sysdev_class to a regular subsystem
  mips: 7segled - convert sysdev_class to a regular subsystem
  sh: dma - convert sysdev_class to a regular subsystem
  sh: intc - convert sysdev_class to a regular subsystem
  power: suspend - convert sysdev_class to a regular subsystem
  power: qe_ic - convert sysdev_class to a regular subsystem
  power: cmm - convert sysdev_class to a regular subsystem
  s390: time - convert sysdev_class to a regular subsystem
  ...

Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
 - arch/arm/mach-exynos/cpu.c
 - arch/arm/mach-exynos/irq-eint.c
 - arch/arm/mach-s3c64xx/common.c
 - arch/arm/mach-s3c64xx/cpu.c
 - arch/arm/mach-s5p64x0/cpu.c
 - arch/arm/mach-s5pv210/common.c
 - arch/arm/plat-samsung/include/plat/cpu.h
 - arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
2012-01-07 12:03:30 -08:00
Glauber Costa
f3f511e1ce net: fix sock_clone reference mismatch with tcp memcontrol
Sockets can also be created through sock_clone. Because it copies
all data in the sock structure, it also copies the memcg-related pointer,
and all should be fine. However, since we now use reference counts in
socket creation, we are left with some sockets that have no reference
counts. It matters when we destroy them, since it leads to a mismatch.

Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: David S. Miller <davem@davemloft.net>
CC: Greg Thelen <gthelen@google.com>
CC: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: Laurent Chavey <chavey@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-07 10:16:34 -08:00
Al Viro
34c80b1d93 vfs: switch ->show_options() to struct dentry *
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06 23:19:54 -05:00
Al Viro
ece2ccb668 Merge branches 'vfsmount-guts', 'umode_t' and 'partitions' into Z 2012-01-06 23:15:54 -05:00
Linus Torvalds
770e1b035d Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm
* 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (207 commits)
  ARM: 7267/1: Remove BUILD_BUG_ON from asm/bug.h
  ARM: 7269/1: mach-sa1100: fix sched_clock breakage
  ARM: 7198/1: arm/imx6: add restart support for imx6q
  ARM: restart: remove the now empty arch_reset()
  ARM: restart: remove comments about adding code to arch_reset()
  ARM: restart: lpc32xx & u300: remove unnecessary printk
  ARM: restart: plat-samsung: remove plat/reset.h and s5p_reset_hook
  ARM: restart: w90x900: use new restart hook
  ARM: restart: Versatile Express: use new restart hook
  ARM: restart: versatile: use new restart hook
  ARM: restart: u300: use new restart hook
  ARM: restart: tegra: use new restart hook
  ARM: restart: spear: use new restart hook
  ARM: restart: shark: use new restart hook
  ARM: restart: sa1100: use new restart hook
  ARM: 7252/1: restart: S5PV210: use new restart hook
  ARM: 7251/1: restart: S5PC100: use new restart hook
  ARM: 7250/1: restart: S5P64X0: use new restart hook
  ARM: 7266/1: restart: S3C64XX: use new restart hook
  ARM: 7265/1: restart: S3C24XX: use new restart hook
  ...

Fix up trivial conflict in arch/arm/mm/init.c due to removal of
memblock_init() clashing with the movement of the sorting of the meminfo
array.
2012-01-06 18:15:25 -08:00
Linus Torvalds
9753dfe19a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1958 commits)
  net: pack skb_shared_info more efficiently
  net_sched: red: split red_parms into parms and vars
  net_sched: sfq: extend limits
  cnic: Improve error recovery on bnx2x devices
  cnic: Re-init dev->stats_addr after chip reset
  net_sched: Bug in netem reordering
  bna: fix sparse warnings/errors
  bna: make ethtool_ops and strings const
  xgmac: cleanups
  net: make ethtool_ops const
  vmxnet3" make ethtool ops const
  xen-netback: make ops structs const
  virtio_net: Pass gfp flags when allocating rx buffers.
  ixgbe: FCoE: Add support for ndo_get_fcoe_hbainfo() call
  netdev: FCoE: Add new ndo_get_fcoe_hbainfo() call
  igb: reset PHY after recovering from PHY power down
  igb: add basic runtime PM support
  igb: Add support for byte queue limits.
  e1000: cleanup CE4100 MDIO registers access
  e1000: unmap ce4100_gbe_mdio_base_virt in e1000_remove
  ...
2012-01-06 17:22:09 -08:00
Linus Torvalds
69734b644b Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86: Fix atomic64_xxx_cx8() functions
  x86: Fix and improve cmpxchg_double{,_local}()
  x86_64, asm: Optimise fls(), ffs() and fls64()
  x86, bitops: Move fls64.h inside __KERNEL__
  x86: Fix and improve percpu_cmpxchg{8,16}b_double()
  x86: Report cpb and eff_freq_ro flags correctly
  x86/i386: Use less assembly in strlen(), speed things up a bit
  x86: Use the same node_distance for 32 and 64-bit
  x86: Fix rflags in FAKE_STACK_FRAME
  x86: Clean up and extend do_int3()
  x86: Call do_notify_resume() with interrupts enabled
  x86/div64: Add a micro-optimization shortcut if base is power of two
  x86-64: Cleanup some assembly entry points
  x86-64: Slightly shorten line system call entry and exit paths
  x86-64: Reduce amount of redundant code generated for invalidate_interruptNN
  x86-64: Slightly shorten int_ret_from_sys_call
  x86, efi: Convert efi_phys_get_time() args to physical addresses
  x86: Default to vsyscall=emulate
  x86-64: Set siginfo and context on vsyscall emulation faults
  x86: consolidate xchg and xadd macros
  ...
2012-01-06 13:59:14 -08:00
Greg Kroah-Hartman
ff4b8a57f0 Merge branch 'driver-core-next' into Linux 3.2
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file,
and it fixes the build error in the arch/x86/kernel/microcode_core.c
file, that the merge did not catch.

The microcode_core.c patch was provided by Stephen Rothwell
<sfr@canb.auug.org.au> who was invaluable in the merge issues involved
with the large sysdev removal process in the driver-core tree.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-06 11:42:52 -08:00
Linus Torvalds
4a2164a7db Merge branch 'core-memblock-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-memblock-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  memblock: Reimplement memblock allocation using reverse free area iterator
  memblock: Kill early_node_map[]
  score: Use HAVE_MEMBLOCK_NODE_MAP
  s390: Use HAVE_MEMBLOCK_NODE_MAP
  mips: Use HAVE_MEMBLOCK_NODE_MAP
  ia64: Use HAVE_MEMBLOCK_NODE_MAP
  SuperH: Use HAVE_MEMBLOCK_NODE_MAP
  sparc: Use HAVE_MEMBLOCK_NODE_MAP
  powerpc: Use HAVE_MEMBLOCK_NODE_MAP
  memblock: Implement memblock_add_node()
  memblock: s/memblock_analyze()/memblock_allow_resize()/ and update users
  memblock: Track total size of regions automatically
  powerpc: Cleanup memblock usage
  memblock: Reimplement memblock_enforce_memory_limit() using __memblock_remove()
  memblock: Make memblock functions handle overflowing range @size
  memblock: Reimplement __memblock_remove() using memblock_isolate_range()
  memblock: Separate out memblock_isolate_range() from memblock_set_node()
  memblock: Kill memblock_init()
  memblock: Kill sentinel entries at the end of static region arrays
  memblock: Add __memblock_dump_all()
  ...
2012-01-06 07:54:53 -08:00
Russell King
2e0e943436 Merge branch 'devel-stable' into for-linus
Conflicts:
	arch/arm/kernel/setup.c
	arch/arm/mach-shmobile/board-kota2.c
2012-01-05 13:24:33 +00:00
Jan Beulich
cdcd629869 x86: Fix and improve cmpxchg_double{,_local}()
Just like the per-CPU ones they had several
problems/shortcomings:

Only the first memory operand was mentioned in the asm()
operands, and the 2x64-bit version didn't have a memory clobber
while the 2x32-bit one did. The former allowed the compiler to
not recognize the need to re-load the data in case it had it
cached in some register, while the latter was overly
destructive.

The types of the local copies of the old and new values were
incorrect (the types of the pointed-to variables should be used
here, to make sure the respective old/new variable types are
compatible).

The __dummy/__junk variables were pointless, given that local
copies of the inputs already existed (and can hence be used for
discarded outputs).

The 32-bit variant of cmpxchg_double_local() referenced
cmpxchg16b_local().

At once also:

 - change the return value type to what it really is: 'bool'
 - unify 32- and 64-bit variants
 - abstract out the common part of the 'normal' and 'local' variants

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/4F01F12A020000780006A19B@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-04 15:01:54 +01:00
Al Viro
649fc7b1b0 should_remove_suid(): inode->i_mode is umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:14 -05:00
Al Viro
09208d150b shmem, ramfs: propagate umode_t, open-coded S_ISREG
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:07 -05:00
Al Viro
f4ae40a6a5 switch debugfs to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:56 -05:00
Al Viro
1a67aafb5f switch ->mknod() to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:54 -05:00
Al Viro
4acdaf27eb switch ->create() to umode_t
vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro
18bb1db3e7 switch vfs_mkdir() and ->mkdir() to umode_t
vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro
ff01bb4832 fs: move code out of buffer.c
Move invalidate_bdev, block_sync_page into fs/block_dev.c.  Export
kill_bdev as well, so brd doesn't have to open code it.  Reduce
buffer_head.h requirement accordingly.

Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving.  The small comment replacing it says enough.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:07 -05:00
Al Viro
6b520e0565 vfs: fix the stupidity with i_dentry in inode destructors
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:52:40 -05:00
David S. Miller
7f8e3234c5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2011-12-30 13:04:14 -05:00
Hillf Danton
b0365c8d0c mm: hugetlb: fix non-atomic enqueue of huge page
If a huge page is enqueued under the protection of hugetlb_lock, then the
operation is atomic and safe.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>		[2.6.37+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-29 16:31:57 -08:00
KOSAKI Motohiro
e26a51148f mm/mempolicy.c: refix mbind_range() vma issue
commit 8aacc9f550 ("mm/mempolicy.c: fix pgoff in mbind vma merge") is the
slightly incorrect fix.

Why? Think following case.

1. map 4 pages of a file at offset 0

   [0123]

2. map 2 pages just after the first mapping of the same file but with
   page offset 2

   [0123][23]

3. mbind() 2 pages from the first mapping at offset 2.
   mbind_range() should treat new vma is,

   [0123][23]
     |23|
     mbind vma

   but it does

   [0123][23]
     |01|
     mbind vma

   Oops. then, it makes wrong vma merge and splitting ([01][0123] or similar).

This patch fixes it.

[testcase]
  test result - before the patch

	case4: 126: test failed. expect '2,4', actual '2,2,2'
       	case5: passed
	case6: passed
	case7: passed
	case8: passed
	case_n: 246: test failed. expect '4,2', actual '1,4'

	------------[ cut here ]------------
	kernel BUG at mm/filemap.c:135!
	invalid opcode: 0000 [#4] SMP DEBUG_PAGEALLOC

	(snip long bug on messages)

  test result - after the patch

	case4: passed
       	case5: passed
	case6: passed
	case7: passed
	case8: passed
	case_n: passed

  source:  mbind_vma_test.c
============================================================
 #include <numaif.h>
 #include <numa.h>
 #include <sys/mman.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>

static unsigned long pagesize;
void* mmap_addr;
struct bitmask *nmask;
char buf[1024];
FILE *file;
char retbuf[10240] = "";
int mapped_fd;

char *rubysrc = "ruby -e '\
  pid = %d; \
  vstart = 0x%llx; \
  vend = 0x%llx; \
  s = `pmap -q #{pid}`; \
  rary = []; \
  s.each_line {|line|; \
    ary=line.split(\" \"); \
    addr = ary[0].to_i(16); \
    if(vstart <= addr && addr < vend) then \
      rary.push(ary[1].to_i()/4); \
    end; \
  }; \
  print rary.join(\",\"); \
'";

void init(void)
{
	void* addr;
	char buf[128];

	nmask = numa_allocate_nodemask();
	numa_bitmask_setbit(nmask, 0);

	pagesize = getpagesize();

	sprintf(buf, "%s", "mbind_vma_XXXXXX");
	mapped_fd = mkstemp(buf);
	if (mapped_fd == -1)
		perror("mkstemp "), exit(1);
	unlink(buf);

	if (lseek(mapped_fd, pagesize*8, SEEK_SET) < 0)
		perror("lseek "), exit(1);
	if (write(mapped_fd, "\0", 1) < 0)
		perror("write "), exit(1);

	addr = mmap(NULL, pagesize*8, PROT_NONE,
		    MAP_SHARED, mapped_fd, 0);
	if (addr == MAP_FAILED)
		perror("mmap "), exit(1);

	if (mprotect(addr+pagesize, pagesize*6, PROT_READ|PROT_WRITE) < 0)
		perror("mprotect "), exit(1);

	mmap_addr = addr + pagesize;

	/* make page populate */
	memset(mmap_addr, 0, pagesize*6);
}

void fin(void)
{
	void* addr = mmap_addr - pagesize;
	munmap(addr, pagesize*8);

	memset(buf, 0, sizeof(buf));
	memset(retbuf, 0, sizeof(retbuf));
}

void mem_bind(int index, int len)
{
	int err;

	err = mbind(mmap_addr+pagesize*index, pagesize*len,
		    MPOL_BIND, nmask->maskp, nmask->size, 0);
	if (err)
		perror("mbind "), exit(err);
}

void mem_interleave(int index, int len)
{
	int err;

	err = mbind(mmap_addr+pagesize*index, pagesize*len,
		    MPOL_INTERLEAVE, nmask->maskp, nmask->size, 0);
	if (err)
		perror("mbind "), exit(err);
}

void mem_unbind(int index, int len)
{
	int err;

	err = mbind(mmap_addr+pagesize*index, pagesize*len,
		    MPOL_DEFAULT, NULL, 0, 0);
	if (err)
		perror("mbind "), exit(err);
}

void Assert(char *expected, char *value, char *name, int line)
{
	if (strcmp(expected, value) == 0) {
		fprintf(stderr, "%s: passed\n", name);
		return;
	}
	else {
		fprintf(stderr, "%s: %d: test failed. expect '%s', actual '%s'\n",
			name, line,
			expected, value);
//		exit(1);
	}
}

/*
      AAAA
    PPPPPPNNNNNN
    might become
    PPNNNNNNNNNN
    case 4 below
*/
void case4(void)
{
	init();
	sprintf(buf, rubysrc, getpid(), mmap_addr, mmap_addr+pagesize*6);

	mem_bind(0, 4);
	mem_unbind(2, 2);

	file = popen(buf, "r");
	fread(retbuf, sizeof(retbuf), 1, file);
	Assert("2,4", retbuf, "case4", __LINE__);

	fin();
}

/*
       AAAA
 PPPPPPNNNNNN
 might become
 PPPPPPPPPPNN
 case 5 below
*/
void case5(void)
{
	init();
	sprintf(buf, rubysrc, getpid(), mmap_addr, mmap_addr+pagesize*6);

	mem_bind(0, 2);
	mem_bind(2, 2);

	file = popen(buf, "r");
	fread(retbuf, sizeof(retbuf), 1, file);
	Assert("4,2", retbuf, "case5", __LINE__);

	fin();
}

/*
	    AAAA
	PPPPNNNNXXXX
	might become
	PPPPPPPPPPPP 6
*/
void case6(void)
{
	init();
	sprintf(buf, rubysrc, getpid(), mmap_addr, mmap_addr+pagesize*6);

	mem_bind(0, 2);
	mem_bind(4, 2);
	mem_bind(2, 2);

	file = popen(buf, "r");
	fread(retbuf, sizeof(retbuf), 1, file);
	Assert("6", retbuf, "case6", __LINE__);

	fin();
}

/*
    AAAA
PPPPNNNNXXXX
might become
PPPPPPPPXXXX 7
*/
void case7(void)
{
	init();
	sprintf(buf, rubysrc, getpid(), mmap_addr, mmap_addr+pagesize*6);

	mem_bind(0, 2);
	mem_interleave(4, 2);
	mem_bind(2, 2);

	file = popen(buf, "r");
	fread(retbuf, sizeof(retbuf), 1, file);
	Assert("4,2", retbuf, "case7", __LINE__);

	fin();
}

/*
    AAAA
PPPPNNNNXXXX
might become
PPPPNNNNNNNN 8
*/
void case8(void)
{
	init();
	sprintf(buf, rubysrc, getpid(), mmap_addr, mmap_addr+pagesize*6);

	mem_bind(0, 2);
	mem_interleave(4, 2);
	mem_interleave(2, 2);

	file = popen(buf, "r");
	fread(retbuf, sizeof(retbuf), 1, file);
	Assert("2,4", retbuf, "case8", __LINE__);

	fin();
}

void case_n(void)
{
	init();
	sprintf(buf, rubysrc, getpid(), mmap_addr, mmap_addr+pagesize*6);

	/* make redundunt mappings [0][1234][34][7] */
	mmap(mmap_addr + pagesize*4, pagesize*2, PROT_READ|PROT_WRITE,
	     MAP_FIXED|MAP_SHARED, mapped_fd, pagesize*3);

	/* Expect to do nothing. */
	mem_unbind(2, 2);

	file = popen(buf, "r");
	fread(retbuf, sizeof(retbuf), 1, file);
	Assert("4,2", retbuf, "case_n", __LINE__);

	fin();
}

int main(int argc, char** argv)
{
	case4();
	case5();
	case6();
	case7();
	case8();
	case_n();

	return 0;
}
=============================================================

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Caspar Zhang <caspar@casparzhang.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: <stable@vger.kernel.org>		[3.1.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-29 16:31:57 -08:00
Rafael J. Wysocki
b7ba68c4a0 Merge branch 'pm-sleep' into pm-for-linus
* pm-sleep: (51 commits)
  PM: Drop generic_subsys_pm_ops
  PM / Sleep: Remove forward-only callbacks from AMBA bus type
  PM / Sleep: Remove forward-only callbacks from platform bus type
  PM: Run the driver callback directly if the subsystem one is not there
  PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
  PM / Sleep: Merge internal functions in generic_ops.c
  PM / Sleep: Simplify generic system suspend callbacks
  PM / Hibernate: Remove deprecated hibernation snapshot ioctls
  PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
  PM / Sleep: Recommend [un]lock_system_sleep() over using pm_mutex directly
  PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep()
  PM / Sleep: Make [un]lock_system_sleep() generic
  PM / Sleep: Use the freezer_count() functions in [un]lock_system_sleep() APIs
  PM / Freezer: Remove the "userspace only" constraint from freezer[_do_not]_count()
  PM / Hibernate: Replace unintuitive 'if' condition in kernel/power/user.c with 'else'
  Freezer / sunrpc / NFS: don't allow TASK_KILLABLE sleeps to block the freezer
  PM / Sleep: Unify diagnostic messages from device suspend/resume
  ACPI / PM: Do not save/restore NVS on Asus K54C/K54HR
  PM / Hibernate: Remove deprecated hibernation test modes
  PM / Hibernate: Thaw processes in SNAPSHOT_CREATE_IMAGE ioctl test path
  ...

Conflicts:
	kernel/kmod.c
2011-12-25 23:42:20 +01:00
David S. Miller
abb434cb05 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/bluetooth/l2cap_core.c

Just two overlapping changes, one added an initialization of
a local variable, and another change added a new local variable.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-23 17:13:56 -05:00
Glauber Costa
65c64ce8ee Partial revert "Basic kernel memory functionality for the Memory Controller"
This reverts commit e5671dfae5.

After a follow up discussion with Michal, it was agreed it would
be better to leave the kmem controller with just the tcp files,
deferring the behavior of the other general memory.kmem.* files
for a later time, when more caches are controlled. This is because
generic kmem files are not used by tcp accounting and it is
not clear how other slab caches would fit into the scheme.

We are reverting the original commit so we can track the reference.
Part of the patch is kept, because it was used by the later tcp
code. Conflicts are shown in the bottom. init/Kconfig is removed from
the revert entirely.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
CC: Kirill A. Shutemov <kirill@shutemov.name>
CC: Paul Menage <paul@paulmenage.org>
CC: Greg Thelen <gthelen@google.com>
CC: Johannes Weiner <jweiner@redhat.com>
CC: David S. Miller <davem@davemloft.net>

Conflicts:

	Documentation/cgroups/memory.txt
	mm/memcontrol.c
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-22 22:37:18 -05:00
Christoph Lameter
933393f58f percpu: Remove irqsafe_cpu_xxx variants
We simply say that regular this_cpu use must be safe regardless of
preemption and interrupt state.  That has no material change for x86
and s390 implementations of this_cpu operations.  However, arches that
do not provide their own implementation for this_cpu operations will
now get code generated that disables interrupts instead of preemption.

-tj: This is part of on-going percpu API cleanup.  For detailed
     discussion of the subject, please refer to the following thread.

     http://thread.gmane.org/gmane.linux.kernel/1222078

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <alpine.DEB.2.00.1112221154380.11787@router.home>
2011-12-22 10:40:20 -08:00
Dave Kleikamp
e6f67b8c05 vfs: __read_cache_page should use gfp argument rather than GFP_KERNEL
lockdep reports a deadlock in jfs because a special inode's rw semaphore
is taken recursively.  The mapping's gfp mask is GFP_NOFS, but is not
used when __read_cache_page() calls add_to_page_cache_lru().

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-21 17:02:46 -08:00
Kay Sievers
10fbcf4c6c convert 'memory' sysdev_class to a regular subsystem
This moves the 'memory sysdev_class' over to a regular 'memory' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.

After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-21 14:48:43 -08:00
Rafael J. Wysocki
b00f4dc5ff Merge branch 'master' into pm-sleep
* master: (848 commits)
  SELinux: Fix RCU deref check warning in sel_netport_insert()
  binary_sysctl(): fix memory leak
  mm/vmalloc.c: remove static declaration of va from __get_vm_area_node
  ipmi_watchdog: restore settings when BMC reset
  oom: fix integer overflow of points in oom_badness
  memcg: keep root group unchanged if creation fails
  nilfs2: potential integer overflow in nilfs_ioctl_clean_segments()
  nilfs2: unbreak compat ioctl
  cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask
  evm: prevent racing during tfm allocation
  evm: key must be set once during initialization
  mmc: vub300: fix type of firmware_rom_wait_states module parameter
  Revert "mmc: enable runtime PM by default"
  mmc: sdhci: remove "state" argument from sdhci_suspend_host
  x86, dumpstack: Fix code bytes breakage due to missing KERN_CONT
  IB/qib: Correct sense on freectxts increment and decrement
  RDMA/cma: Verify private data length
  cgroups: fix a css_set not found bug in cgroup_attach_proc
  oprofile: Fix uninitialized memory access when writing to writing to oprofilefs
  Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel"
  ...

Conflicts:
	kernel/cgroup_freezer.c
2011-12-21 21:59:45 +01:00
Kautuk Consul
0006526d78 mm/vmalloc.c: remove static declaration of va from __get_vm_area_node
Static storage is not required for the struct vmap_area in
__get_vm_area_node.

Removing "static" to store this variable on the stack instead.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-20 10:25:04 -08:00
Frantisek Hrbata
ff05b6f7ae oom: fix integer overflow of points in oom_badness
An integer overflow will happen on 64bit archs if task's sum of rss,
swapents and nr_ptes exceeds (2^31)/1000 value.  This was introduced by
commit

f755a04 oom: use pte pages in OOM score

where the oom score computation was divided into several steps and it's no
longer computed as one expression in unsigned long(rss, swapents, nr_pte
are unsigned long), where the result value assigned to points(int) is in
range(1..1000).  So there could be an int overflow while computing

176          points *= 1000;

and points may have negative value. Meaning the oom score for a mem hog task
will be one.

196          if (points <= 0)
197                  return 1;

For example:
[ 3366]     0  3366 35390480 24303939   5       0             0 oom01
Out of memory: Kill process 3366 (oom01) score 1 or sacrifice child

Here the oom1 process consumes more than 24303939(rss)*4096~=92GB physical
memory, but it's oom score is one.

In this situation the mem hog task is skipped and oom killer kills another and
most probably innocent task with oom score greater than one.

The points variable should be of type long instead of int to prevent the
int overflow.

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>		[2.6.36+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-20 10:25:04 -08:00
Hillf Danton
a41c58a666 memcg: keep root group unchanged if creation fails
If the request is to create non-root group and we fail to meet it, we
should leave the root unchanged.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-20 10:25:04 -08:00
Ingo Molnar
45aa0663cc Merge branch 'memblock-kill-early_node_map' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/memblock 2011-12-20 12:14:26 +01:00
Wu Fengguang
bdaac4902a writeback: balanced_rate cannot exceed write bandwidth
Add an upper limit to balanced_rate according to the below inequality.
This filters out some rare but huge singular points, which at least
enables more readable gnuplot figures.

When there are N dd dirtiers,

	balanced_dirty_ratelimit = write_bw / N

So it holds that

	balanced_dirty_ratelimit <= write_bw

The singular points originate from dirty_rate in the below formular:

        balanced_dirty_ratelimit = task_ratelimit * write_bw / dirty_rate
where
	dirty_rate = (number of page dirties in the past 200ms) / 200ms

In the extreme case, if all dd tasks suddenly get blocked on something
else and hence no pages are dirtied at all, dirty_rate will be 0 and
balanced_dirty_ratelimit will be inf. This could happen in reality.

Note that these huge singular points are not a real threat, since they
are _guaranteed_ to be filtered out by the
	min(balanced_dirty_ratelimit, task_ratelimit)
line in bdi_update_dirty_ratelimit(). task_ratelimit is based on the
number of dirty pages, which will never _suddenly_ fly away like
balanced_dirty_ratelimit. So any weirdly large balanced_dirty_ratelimit
will be cut down to the level of task_ratelimit.

There won't be tiny singular points though, as long as the dirty pages
lie inside the dirty throttling region (above the freerun region).
Because there the dd tasks will be throttled by balanced_dirty_pages()
and won't be able to suddenly dirty much more pages than average.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:33 +08:00
Wu Fengguang
8279194054 writeback: do strict bdi dirty_exceeded
This helps to reduce dirty throttling polls and hence CPU overheads.

bdi->dirty_exceeded typically only helps when suddenly starting 100+
dd's on a disk, in which case the dd's may need to poll
balance_dirty_pages() earlier than tsk->nr_dirtied_pause.

CC: Jan Kara <jack@suse.cz>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:31 +08:00
Wu Fengguang
5b9b357435 writeback: avoid tiny dirty poll intervals
The LKP tests see big 56% regression for the case fio_mmap_randwrite_64k.
Shaohua manages to root cause it to be the much smaller dirty pause times
and hence much more frequent invocations to the IO-less balance_dirty_pages().
Since fio_mmap_randwrite_64k effectively contains both reads and writes,
the more frequent pauses triggered more idling in the cfq IO scheduler.

The solution is to increase pause time all the way up to the max 200ms
in this case, which is found to restore most performance. This will help
reduce CPU overheads in other cases, too.

Note that I don't expect many performance critical workloads to run this
access pattern: the mmap read-on-write is rather inefficient and could
be avoided by doing normal writes syscalls.

CC: Jan Kara <jack@suse.cz>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Li Shaohua <shaohua.li@intel.com>
Tested-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:30 +08:00
Wu Fengguang
7ccb9ad536 writeback: max, min and target dirty pause time
Control the pause time and the call intervals to balance_dirty_pages()
with three parameters:

1) max_pause, limited by bdi_dirty and MAX_PAUSE

2) the target pause time, grows with the number of dd tasks
   and is normally limited by max_pause/2

3) the minimal pause, set to half the target pause
   and is used to skip short sleeps and accumulate them into bigger ones

The typical behaviors after patch:

- if ever task_ratelimit is far below dirty_ratelimit, the pause time
  will remain constant at max_pause and nr_dirtied_pause will be
  fluctuating with task_ratelimit

- in the normal cases, nr_dirtied_pause will remain stable (keep in the
  same pace with dirty_ratelimit) and the pause time will be fluctuating
  with task_ratelimit

In summary, someone has to fluctuate with task_ratelimit, because

	task_ratelimit = nr_dirtied_pause / pause

We normally prefer a stable nr_dirtied_pause, until reaching max_pause.

The notable behavior changes are:

- in stable workloads, there will no longer be sudden big trajectory
  switching of nr_dirtied_pause as concerned by Peter. It will be as
  smooth as dirty_ratelimit and changing proportionally with it (as
  always, assuming bdi bandwidth does not fluctuate across 2^N lines,
  otherwise nr_dirtied_pause will show up in 2+ parallel trajectories)

- in the rare cases when something keeps task_ratelimit far below
  dirty_ratelimit, the smoothness can no longer be retained and
  nr_dirtied_pause will be "dancing" with task_ratelimit. This fixes a
  (not that destructive but still not good) bug that
	  dirty_ratelimit gets brought down undesirably
	  <= balanced_dirty_ratelimit is under estimated
	  <= weakly executed task_ratelimit
	  <= pause goes too large and gets trimmed down to max_pause
	  <= nr_dirtied_pause (based on dirty_ratelimit) is set too large
	  <= dirty_ratelimit being much larger than task_ratelimit

- introduce min_pause to avoid small pause sleeps

- when pause is trimmed down to max_pause, try to compensate it at the
  next pause time

The "refactor" type of changes are:

The max_pause equation is slightly transformed to make it slightly more
efficient.

We now scale target_pause by (N * 10ms) on 2^N concurrent tasks, which
is effectively equal to the original scaling max_pause by (N * 20ms)
because the original code does implicit target_pause ~= max_pause / 2.
Based on the same implicit ratio, target_pause starts with 10ms on 1 dd.

CC: Jan Kara <jack@suse.cz>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:28 +08:00
Wu Fengguang
83712358ba writeback: dirty ratelimit - think time compensation
Compensate the task's think time when computing the final pause time,
so that ->dirty_ratelimit can be executed accurately.

        think time := time spend outside of balance_dirty_pages()

In the rare case that the task slept longer than the 200ms period time
(result in negative pause time), the sleep time will be compensated in
the following periods, too, if it's less than 1 second.

Accumulated errors are carefully avoided as long as the max pause area
is not hitted.

Pseudo code:

        period = pages_dirtied / task_ratelimit;
        think = jiffies - dirty_paused_when;
        pause = period - think;

1) normal case: period > think

        pause = period - think
        dirty_paused_when = jiffies + pause
        nr_dirtied = 0

                             period time
              |===============================>|
                  think time      pause time
              |===============>|==============>|
        ------|----------------|---------------|------------------------
        dirty_paused_when   jiffies

2) no pause case: period <= think

        don't pause; reduce future pause time by:
        dirty_paused_when += period
        nr_dirtied = 0

                           period time
              |===============================>|
                                  think time
              |===================================================>|
        ------|--------------------------------+-------------------|----
        dirty_paused_when                                       jiffies

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:27 +08:00
Wu Fengguang
2f800fbd77 writeback: fix dirtied pages accounting on redirty
De-account the accumulative dirty counters on page redirty.

Page redirties (very common in ext4) will introduce mismatch between
counters (a) and (b)

a) NR_DIRTIED, BDI_DIRTIED, tsk->nr_dirtied
b) NR_WRITTEN, BDI_WRITTEN

This will introduce systematic errors in balanced_rate and result in
dirty page position errors (ie. the dirty pages are no longer balanced
around the global/bdi setpoints).

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:23 +08:00
Wu Fengguang
d3bc1fef93 writeback: fix dirtied pages accounting on sub-page writes
When dd in 512bytes, generic_perform_write() calls
balance_dirty_pages_ratelimited() 8 times for the same page, but
obviously the page is only dirtied once.

Fix it by accounting tsk->nr_dirtied and bdp_ratelimits at page dirty time.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:22 +08:00
Wu Fengguang
54848d73f9 writeback: charge leaked page dirties to active tasks
It's a years long problem that a large number of short-lived dirtiers
(eg. gcc instances in a fast kernel build) may starve long-run dirtiers
(eg. dd) as well as pushing the dirty pages to the global hard limit.

The solution is to charge the pages dirtied by the exited gcc to the
other random dirtying tasks. It sounds not perfect, however should
behave good enough in practice, seeing as that throttled tasks aren't
actually running so those that are running are more likely to pick it up
and get throttled, therefore promoting an equal spread.

Randy: fix compile error: 'dirty_throttle_leaks' undeclared in exit.c

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:20 +08:00
Eugene Surovegin
9f57bd4d6d percpu: fix per_cpu_ptr_to_phys() handling of non-page-aligned addresses
per_cpu_ptr_to_phys() incorrectly rounds up its result for non-kmalloc
case to the page boundary, which is bogus for any non-page-aligned
address.

This affects the only in-tree user of this function - sysfs handler
for per-cpu 'crash_notes' physical address.  The trouble is that the
crash_notes per-cpu variable is not page-aligned:

crash_notes = 0xc08e8ed4
PER-CPU OFFSET VALUES:
 CPU 0: 3711f000
 CPU 1: 37129000
 CPU 2: 37133000
 CPU 3: 3713d000

So, the per-cpu addresses are:
 crash_notes on CPU 0: f7a07ed4 => phys 36b57ed4
 crash_notes on CPU 1: f7a11ed4 => phys 36b4ded4
 crash_notes on CPU 2: f7a1bed4 => phys 36b43ed4
 crash_notes on CPU 3: f7a25ed4 => phys 36b39ed4

However, /sys/devices/system/cpu/cpu*/crash_notes says:
 /sys/devices/system/cpu/cpu0/crash_notes: 36b57000
 /sys/devices/system/cpu/cpu1/crash_notes: 36b4d000
 /sys/devices/system/cpu/cpu2/crash_notes: 36b43000
 /sys/devices/system/cpu/cpu3/crash_notes: 36b39000

As you can see, all values are rounded down to a page
boundary. Consequently, this is where kexec sets up the NOTE segments,
and thus where the secondary kernel is looking for them. However, when
the first kernel crashes, it saves the notes to the unaligned
addresses, where they are not found.

Fix it by adding offset_in_page() to the translated page address.

-tj: Combined Eugene's and Petr's commit messages.

Signed-off-by: Eugene Surovegin <ebs@ebshome.net>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Petr Tesarik <ptesarik@suse.cz>
Cc: stable@kernel.org
2011-12-15 11:41:40 -08:00
Linus Torvalds
4dde6dedad Merge branch 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
* 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: set max_pause to lowest value on zero bdi_dirty
  writeback: permit through good bdi even when global dirty exceeded
  writeback: comment on the bdi dirty threshold
  fs: Make write(2) interruptible by a fatal signal
  writeback: Fix issue on make htmldocs
2011-12-13 14:58:56 -08:00
Shaohua Li
b13683d1cc slub: add missed accounting
With per-cpu partial list, slab is added to partial list first and then moved
to node list. The __slab_free() code path for add/remove_partial is almost
deprecated(except for slub debug). But we forget to account add/remove_partial
when move per-cpu partial pages to node list, so the statistics for such events
are always 0. Add corresponding accounting.

This is against the patch "slub: use correct parameter to add a page to
partial list tail"

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-12-13 22:27:09 +02:00
Christoph Lameter
213eeb9fd9 slub: Extract get_freelist from __slab_alloc
get_freelist retrieves free objects from the page freelist (put there by remote
frees) or deactivates a slab page if no more objects are available.

Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-12-13 22:17:10 +02:00
Christoph Lameter
8f1e33daed slub: Switch per cpu partial page support off for debugging
Eric saw an issue with accounting of slabs during validation. Its not
possible to determine accurately how many per cpu partial slabs exist at
any time so this switches off per cpu partial pages during debug.

Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-12-13 22:14:02 +02:00
Eric Dumazet
73736e0387 slub: fix a possible memleak in __slab_alloc()
Zhihua Che reported a possible memleak in slub allocator on
CONFIG_PREEMPT=y builds.

It is possible current thread migrates right before disabling irqs in
__slab_alloc(). We must check again c->freelist, and perform a normal
allocation instead of scratching c->freelist.

Many thanks to Zhihua Che for spotting this bug, introduced in 2.6.39

V2: Its also possible an IRQ freed one (or several) object(s) and
populated c->freelist, so its not a CONFIG_PREEMPT only problem.

Cc: <stable@vger.kernel.org>        [2.6.39+]
Reported-by: Zhihua Che <zhihua.che@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-12-13 22:11:21 +02:00
Tejun Heo
2f7ee5691e cgroup: introduce cgroup_taskset and use it in subsys->can_attach(), cancel_attach() and attach()
Currently, there's no way to pass multiple tasks to cgroup_subsys
methods necessitating the need for separate per-process and per-task
methods.  This patch introduces cgroup_taskset which can be used to
pass multiple tasks and their associated cgroups to cgroup_subsys
methods.

Three methods - can_attach(), cancel_attach() and attach() - are
converted to use cgroup_taskset.  This unifies passed parameters so
that all methods have access to all information.  Conversions in this
patchset are identical and don't introduce any behavior change.

-v2: documentation updated as per Paul Menage's suggestion.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul Menage <paul@paulmenage.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: James Morris <jmorris@namei.org>
2011-12-12 18:12:21 -08:00
Glauber Costa
d1a4c0b37c tcp memory pressure controls
This patch introduces memory pressure controls for the tcp
protocol. It uses the generic socket memory pressure code
introduced in earlier patches, and fills in the
necessary data in cg_proto struct.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtisu.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12 19:04:10 -05:00
Glauber Costa
e1aab161e0 socket: initial cgroup code.
The goal of this work is to move the memory pressure tcp
controls to a cgroup, instead of just relying on global
conditions.

To avoid excessive overhead in the network fast paths,
the code that accounts allocated memory to a cgroup is
hidden inside a static_branch(). This branch is patched out
until the first non-root cgroup is created. So when nobody
is using cgroups, even if it is mounted, no significant performance
penalty should be seen.

This patch handles the generic part of the code, and has nothing
tcp-specific.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtsu.com>
CC: Kirill A. Shutemov <kirill@shutemov.name>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12 19:04:10 -05:00
Glauber Costa
e5671dfae5 Basic kernel memory functionality for the Memory Controller
This patch lays down the foundation for the kernel memory component
of the Memory Controller.

As of today, I am only laying down the following files:

 * memory.independent_kmem_limit
 * memory.kmem.limit_in_bytes (currently ignored)
 * memory.kmem.usage_in_bytes (always zero)

Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: Kirill A. Shutemov <kirill@shutemov.name>
CC: Paul Menage <paul@paulmenage.org>
CC: Greg Thelen <gthelen@google.com>
CC: Johannes Weiner <jweiner@redhat.com>
CC: Michal Hocko <mhocko@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-12 19:03:55 -05:00
Mel Gorman
1368edf064 mm: vmalloc: check for page allocation failure before vmlist insertion
Commit f5252e00 ("mm: avoid null pointer access in vm_struct via
/proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after
it is fully initialised.  Unfortunately, it did not check that
__vmalloc_area_node() successfully populated the area.  In the event of
allocation failure, the vmalloc area is freed but the pointer to freed
memory is inserted into the vmlist leading to a a crash later in
get_vmalloc_info().

This patch adds a check for ____vmalloc_area_node() failure within
__vmalloc_node_range.  It does not use "goto fail" as in the previous
error path as a warning was already displayed by __vmalloc_area_node()
before it called vfree in its failure path.

Credit goes to Luciano Chavez for doing all the real work of identifying
exactly where the problem was.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com>
Tested-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>		[3.1.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:29 -08:00
Michal Hocko
d021563888 mm: Ensure that pfn_valid() is called once per pageblock when reserving pageblocks
setup_zone_migrate_reserve() expects that zone->start_pfn starts at
pageblock_nr_pages aligned pfn otherwise we could access beyond an
existing memblock resulting in the following panic if
CONFIG_HOLES_IN_ZONE is not configured and we do not check pfn_valid:

  IP: [<c02d331d>] setup_zone_migrate_reserve+0xcd/0x180
  *pdpt = 0000000000000000 *pde = f000ff53f000ff53
  Oops: 0000 [#1] SMP
  Pid: 1, comm: swapper Not tainted 3.0.7-0.7-pae #1 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform
  EIP: 0060:[<c02d331d>] EFLAGS: 00010006 CPU: 0
  EIP is at setup_zone_migrate_reserve+0xcd/0x180
  EAX: 000c0000 EBX: f5801fc0 ECX: 000c0000 EDX: 00000000
  ESI: 000c01fe EDI: 000c01fe EBP: 00140000 ESP: f2475f58
  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
  Process swapper (pid: 1, ti=f2474000 task=f2472cd0 task.ti=f2474000)
  Call Trace:
  [<c02d389c>] __setup_per_zone_wmarks+0xec/0x160
  [<c02d3a1f>] setup_per_zone_wmarks+0xf/0x20
  [<c08a771c>] init_per_zone_wmark_min+0x27/0x86
  [<c020111b>] do_one_initcall+0x2b/0x160
  [<c086639d>] kernel_init+0xbe/0x157
  [<c05cae26>] kernel_thread_helper+0x6/0xd
  Code: a5 39 f5 89 f7 0f 46 fd 39 cf 76 40 8b 03 f6 c4 08 74 32 eb 91 90 89 c8 c1 e8 0e 0f be 80 80 2f 86 c0 8b 14 85 60 2f 86 c0 89 c8 <2b> 82 b4 12 00 00 c1 e0 05 03 82 ac 12 00 00 8b 00 f6 c4 08 0f
  EIP: [<c02d331d>] setup_zone_migrate_reserve+0xcd/0x180 SS:ESP 0068:f2475f58
  CR2: 00000000000012b4

We crashed in pageblock_is_reserved() when accessing pfn 0xc0000 because
highstart_pfn = 0x36ffe.

The issue was introduced in 3.0-rc1 by 6d3163ce ("mm: check if any page
in a pageblock is reserved before marking it MIGRATE_RESERVE").

Make sure that start_pfn is always aligned to pageblock_nr_pages to
ensure that pfn_valid s always called at the start of each pageblock.
Architectures with holes in pageblocks will be correctly handled by
pfn_valid_within in pageblock_is_reserved.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Tested-by: Dang Bo <bdang@vmware.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Arve Hjnnevg <arve@android.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>	[3.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:28 -08:00
Hillf Danton
09761333ed mm/migrate.c: pair unlock_page() and lock_page() when migrating huge pages
Avoid unlocking and unlocked page if we failed to lock it.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:28 -08:00
Youquan Song
58a84aa927 thp: set compound tail page _count to zero
Commit 70b50f94f1 ("mm: thp: tail page refcounting fix") keeps all
page_tail->_count zero at all times.  But the current kernel does not
set page_tail->_count to zero if a 1GB page is utilized.  So when an
IOMMU 1GB page is used by KVM, it wil result in a kernel oops because a
tail page's _count does not equal zero.

  kernel BUG at include/linux/mm.h:386!
  invalid opcode: 0000 [#1] SMP
  Call Trace:
    gup_pud_range+0xb8/0x19d
    get_user_pages_fast+0xcb/0x192
    ? trace_hardirqs_off+0xd/0xf
    hva_to_pfn+0x119/0x2f2
    gfn_to_pfn_memslot+0x2c/0x2e
    kvm_iommu_map_pages+0xfd/0x1c1
    kvm_iommu_map_memslots+0x7c/0xbd
    kvm_iommu_map_guest+0xaa/0xbf
    kvm_vm_ioctl_assigned_device+0x2ef/0xa47
    kvm_vm_ioctl+0x36c/0x3a2
    do_vfs_ioctl+0x49e/0x4e4
    sys_ioctl+0x5a/0x7c
    system_call_fastpath+0x16/0x1b
  RIP  gup_huge_pud+0xf2/0x159

Signed-off-by: Youquan Song <youquan.song@intel.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:28 -08:00
Andrea Arcangeli
1dfb059b94 thp: reduce khugepaged freezing latency
khugepaged can sometimes cause suspend to fail, requiring that the user
retry the suspend operation.

Use wait_event_freezable_timeout() instead of
schedule_timeout_interruptible() to avoid missing freezer wakeups.  A
try_to_freeze() would have been needed in the khugepaged_alloc_hugepage
tight loop too in case of the allocation failing repeatedly, and
wait_event_freezable_timeout will provide it too.

khugepaged would still freeze just fine by trying again the next minute
but it's better if it freezes immediately.

Reported-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Jiri Slaby <jslaby@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:28 -08:00
Konstantin Khlebnikov
83aeeada7c vmscan: use atomic-long for shrinker batching
Use atomic-long operations instead of looping around cmpxchg().

[akpm@linux-foundation.org: massage atomic.h inclusions]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:27 -08:00
Konstantin Khlebnikov
635697c663 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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:27 -08:00
Tejun Heo
7bd0b0f0da memblock: Reimplement memblock allocation using reverse free area iterator
Now that all early memory information is in memblock when enabled, we
can implement reverse free area iterator and use it to implement NUMA
aware allocator which is then wrapped for simpler variants instead of
the confusing and inefficient mending of information in separate NUMA
aware allocator.

Implement for_each_free_mem_range_reverse(), use it to reimplement
memblock_find_in_range_node() which in turn is used by all allocators.

The visible allocator interface is inconsistent and can probably use
some cleanup too.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:09 -08:00
Tejun Heo
0ee332c145 memblock: Kill early_node_map[]
Now all ARCH_POPULATES_NODE_MAP archs select HAVE_MEBLOCK_NODE_MAP -
there's no user of early_node_map[] left.  Kill early_node_map[] and
replace ARCH_POPULATES_NODE_MAP with HAVE_MEMBLOCK_NODE_MAP.  Also,
relocate for_each_mem_pfn_range() and helper from mm.h to memblock.h
as page_alloc.c would no longer host an alternative implementation.

This change is ultimately one to one mapping and shouldn't cause any
observable difference; however, after the recent changes, there are
some functions which now would fit memblock.c better than page_alloc.c
and dependency on HAVE_MEMBLOCK_NODE_MAP instead of HAVE_MEMBLOCK
doesn't make much sense on some of them.  Further cleanups for
functions inside HAVE_MEMBLOCK_NODE_MAP in mm.h would be nice.

-v2: Fix compile bug introduced by mis-spelling
 CONFIG_HAVE_MEMBLOCK_NODE_MAP to CONFIG_MEMBLOCK_HAVE_NODE_MAP in
 mmzone.h.  Reported by Stephen Rothwell.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2011-12-08 10:22:09 -08:00
Tejun Heo
7fb0bc3f06 memblock: Implement memblock_add_node()
Implement memblock_add_node() which can add a new memblock memory
region with specific node ID.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:08 -08:00
Tejun Heo
1aadc0560f memblock: s/memblock_analyze()/memblock_allow_resize()/ and update users
The only function of memblock_analyze() is now allowing resize of
memblock region arrays.  Rename it to memblock_allow_resize() and
update its users.

* The following users remain the same other than renaming.

  arm/mm/init.c::arm_memblock_init()
  microblaze/kernel/prom.c::early_init_devtree()
  powerpc/kernel/prom.c::early_init_devtree()
  openrisc/kernel/prom.c::early_init_devtree()
  sh/mm/init.c::paging_init()
  sparc/mm/init_64.c::paging_init()
  unicore32/mm/init.c::uc32_memblock_init()

* In the following users, analyze was used to update total size which
  is no longer necessary.

  powerpc/kernel/machine_kexec.c::reserve_crashkernel()
  powerpc/kernel/prom.c::early_init_devtree()
  powerpc/mm/init_32.c::MMU_init()
  powerpc/mm/tlb_nohash.c::__early_init_mmu()  
  powerpc/platforms/ps3/mm.c::ps3_mm_add_memory()
  powerpc/platforms/embedded6xx/wii.c::wii_memory_fixups()
  sh/kernel/machine_kexec.c::reserve_crashkernel()

* x86/kernel/e820.c::memblock_x86_fill() was directly setting
  memblock_can_resize before populating memblock and calling analyze
  afterwards.  Call memblock_allow_resize() before start populating.

memblock_can_resize is now static inside memblock.c.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2011-12-08 10:22:08 -08:00
Tejun Heo
1440c4e2c9 memblock: Track total size of regions automatically
Total size of memory regions was calculated by memblock_analyze()
requiring explicitly calling the function between operations which can
change memory regions and possible users of total size, which is
cumbersome and fragile.

This patch makes each memblock_type track total size automatically
with minor modifications to memblock manipulation functions and remove
requirements on calling memblock_analyze().  [__]memblock_dump_all()
now also dumps the total size of reserved regions.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:08 -08:00
Tejun Heo
c0ce8fef55 memblock: Reimplement memblock_enforce_memory_limit() using __memblock_remove()
With recent updates, the basic memblock operations are robust enough
that there's no reason for memblock_enfore_memory_limit() to directly
manipulate memblock region arrays.  Reimplement it using
__memblock_remove().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:07 -08:00
Tejun Heo
eb18f1b5bf memblock: Make memblock functions handle overflowing range @size
Allow memblock users to specify range where @base + @size overflows
and automatically cap it at maximum.  This makes the interface more
robust and specifying till-the-end-of-memory easier.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:07 -08:00
Tejun Heo
719361809f memblock: Reimplement __memblock_remove() using memblock_isolate_range()
__memblock_remove()'s open coded region manipulation can be trivially
replaced with memblock_islate_range().  This increases code sharing
and eases improving region tracking.

This pulls memblock_isolate_range() out of HAVE_MEMBLOCK_NODE_MAP.
Make it use memblock_get_region_node() instead of assuming rgn->nid is
available.

-v2: Fixed build failure on !HAVE_MEMBLOCK_NODE_MAP caused by direct
     rgn->nid access.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:07 -08:00
Tejun Heo
6a9ceb31c0 memblock: Separate out memblock_isolate_range() from memblock_set_node()
memblock_set_node() operates in three steps - break regions crossing
boundaries, set nid and merge back regions.  This patch separates the
first part into a separate function - memblock_isolate_range(), which
breaks regions crossing range boundaries and returns range index range
for regions properly contained in the specified memory range.

This doesn't introduce any behavior change and will be used to further
unify region handling.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:07 -08:00
Tejun Heo
fe091c208a memblock: Kill memblock_init()
memblock_init() initializes arrays for regions and memblock itself;
however, all these can be done with struct initializers and
memblock_init() can be removed.  This patch kills memblock_init() and
initializes memblock with struct initializer.

The only difference is that the first dummy entries don't have .nid
set to MAX_NUMNODES initially.  This doesn't cause any behavior
difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2011-12-08 10:22:07 -08:00
Tejun Heo
c5a1cb284b memblock: Kill sentinel entries at the end of static region arrays
memblock no longer depends on having one more entry at the end during
addition making the sentinel entries at the end of region arrays not
too useful.  Remove the sentinels.  This eases further updates.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:07 -08:00
Tejun Heo
4ff7b82f1e memblock: Add __memblock_dump_all()
Add __memblock_dump_all() which dumps memblock configuration whether
memblock_debug is enabled or not.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:06 -08:00
Tejun Heo
9c8c27e2b8 memblock: Use memblock_reserve() in memblock internal functions
Make memblock_double_array(), __memblock_alloc_base() and
memblock_alloc_nid() use memblock_reserve() instead of calling
memblock_add_region() with reserved array directly.  This eases
debugging and updates to memblock_add_region().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:06 -08:00
Tejun Heo
581adcbe12 memblock: Make memblock_{add|remove|free|reserve}() return int and update prototypes
memblock_{add|remove|free|reserve}() return either 0 or -errno but had
long as return type.  Chage it to int.  Also, drop 'extern' from all
prototypes in memblock.h - they are unnecessary and used
inconsistently (especially if mm.h is included in the picture).

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
2011-12-08 10:22:06 -08:00
Wu Fengguang
82e230a07d writeback: set max_pause to lowest value on zero bdi_dirty
Some trace shows lots of bdi_dirty=0 lines where it's actually some
small value if w/o the accounting errors in the per-cpu bdi stats.

In this case the max pause time should really be set to the smallest
(non-zero) value to avoid IO queue underrun and improve throughput.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-08 10:49:29 +08:00
Wu Fengguang
c5c6343c4d writeback: permit through good bdi even when global dirty exceeded
On a system with 1 local mount and 1 NFS mount, if the NFS server
becomes not responding when dd to the NFS mount, the NFS dirty pages may
exceed the global dirty limit and _every_ task involving writing will be
blocked. The whole system appears unresponsive.

The workaround is to permit through the bdi's that only has a small
number of dirty pages. The number chosen (bdi_stat_error pages) is not
enough to enable the local disk to run in optimal throughput, however is
enough to make the system responsive on a broken NFS mount. The user can
then kill the dirtiers on the NFS mount and increase the global dirty
limit to bring up the local disk's throughput.

It risks allowing dirty pages to grow much larger than the global dirty
limit when there are 1000+ mounts, however that's very unlikely to happen,
especially in low memory profiles.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-08 10:49:27 +08:00
Wu Fengguang
aed21ad28b writeback: comment on the bdi dirty threshold
We do "floating proportions" to let active devices to grow its target
share of dirty pages and stalled/inactive devices to decrease its target
share over time.

It works well except in the case of "an inactive disk suddenly goes
busy", where the initial target share may be too small. To mitigate
this, bdi_position_ratio() has the below line to raise a small
bdi_thresh when it's safe to do so, so that the disk be feed with enough
dirty pages for efficient IO and in turn fast rampup of bdi_thresh:

        bdi_thresh = max(bdi_thresh, (limit - dirty) / 8);

balance_dirty_pages() normally does negative feedback control which
adjusts ratelimit to balance the bdi dirty pages around the target.
In some extreme cases when that is not enough, it will have to block
the tasks completely until the bdi dirty pages drop below bdi_thresh.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-08 10:49:20 +08:00
Stanislaw Gruszka
54c29c635a mm, x86: Remove debug_pagealloc_enabled
When (no)bootmem finish operation, it pass pages to buddy
allocator. Since debug_pagealloc_enabled is not set, we will do
not protect pages, what is not what we want with
CONFIG_DEBUG_PAGEALLOC=y.

To fix remove debug_pagealloc_enabled. That variable was
introduced by commit 12d6f21e "x86: do not PSE on
CONFIG_DEBUG_PAGEALLOC=y" to get more CPA (change page
attribude) code testing. But currently we have CONFIG_CPA_DEBUG,
which test CPA.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1322582711-14571-1-git-send-email-sgruszka@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 09:24:07 +01:00
Russell King
73829af71f Merge branch 'vmalloc' of git://git.linaro.org/people/nico/linux into devel-stable 2011-12-05 23:27:59 +00:00
Peter Zijlstra
52cef18916 slab, lockdep: Fix silly bug
Commit 30765b92 ("slab, lockdep: Annotate the locks before using
them") moves the init_lock_keys() call from after g_cpucache_up =
FULL, to before it. And overlooks the fact that init_node_lock_keys()
tests for it and ignores everything !FULL.

Introduce a LATE stage and change the lockdep test to be <LATE.

Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 09:44:00 +01:00
Jan Kara
a50527b19c fs: Make write(2) interruptible by a fatal signal
Currently write(2) to a file is not interruptible by any signal.
Sometimes this is desirable, e.g. when you want to quickly kill a
process hogging your disk. Also, with commit 499d05ecf9 ("mm: Make
task in balance_dirty_pages() killable"), it's necessary to abort the
current write accordingly to avoid it quickly dirtying lots more pages
at unthrottled rate.

This patch makes write interruptible by SIGKILL. We do not allow write
to be interruptible by any other signal because that has larger
potential of screwing some badly written applications.

Reported-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Tested-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Acked-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-02 09:17:05 +08:00
Linus Torvalds
57db53b074 Merge branch 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
* 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  slub: avoid potential NULL dereference or corruption
  slub: use irqsafe_cpu_cmpxchg for put_cpu_partial
  slub: move discard_slab out of node lock
  slub: use correct parameter to add a page to partial list tail
2011-11-29 11:13:22 -08:00
Linus Torvalds
9b5a4d4f65 Merge branch 'for-3.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-3.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: explain why per_cpu_ptr_to_phys() is more complicated than necessary
  percpu: fix chunk range calculation
  percpu: rename pcpu_mem_alloc to pcpu_mem_zalloc
2011-11-28 13:49:43 -08:00
Tejun Heo
d4bbf7e775 Merge branch 'master' into x86/memblock
Conflicts & resolutions:

* arch/x86/xen/setup.c

	dc91c728fd "xen: allow extra memory to be in multiple regions"
	24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..."

	conflicted on xen_add_extra_mem() updates.  The resolution is
	trivial as the latter just want to replace
	memblock_x86_reserve_range() with memblock_reserve().

* drivers/pci/intel-iommu.c

	166e9278a3 "x86/ia64: intel-iommu: move to drivers/iommu/"
	5dfe8660a3 "bootmem: Replace work_with_active_regions() with..."

	conflicted as the former moved the file under drivers/iommu/.
	Resolved by applying the chnages from the latter on the moved
	file.

* mm/Kconfig

	6661672053 "memblock: add NO_BOOTMEM config symbol"
	c378ddd53f "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option"

	conflicted trivially.  Both added config options.  Just
	letting both add their own options resolves the conflict.

* mm/memblock.c

	d1f0ece6cd "mm/memblock.c: small function definition fixes"
	ed7b56a799 "memblock: Remove memblock_memory_can_coalesce()"

	confliected.  The former updates function removed by the
	latter.  Resolution is trivial.

Signed-off-by: Tejun Heo <tj@kernel.org>
2011-11-28 09:46:22 -08:00
Shaohua Li
4c493a5a5c slub: add missed accounting
With per-cpu partial list, slab is added to partial list first and then moved
to node list. The __slab_free() code path for add/remove_partial is almost
deprecated(except for slub debug). But we forget to account add/remove_partial
when move per-cpu partial pages to node list, so the statistics for such events
are always 0. Add corresponding accounting.

This is against the patch "slub: use correct parameter to add a page to
partial list tail"

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-11-27 22:08:15 +02:00
Pekka Enberg
42616cacf8 Merge branch 'slab/urgent' into slab/next 2011-11-27 22:08:03 +02:00
Eric Dumazet
bc6697d8a5 slub: avoid potential NULL dereference or corruption
show_slab_objects() can trigger NULL dereferences or memory corruption.

Another cpu can change its c->page to NULL or c->node to NUMA_NO_NODE
while we use them.

Use ACCESS_ONCE(c->page) and ACCESS_ONCE(c->node) to make sure this
cannot happen.

Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-11-24 08:44:19 +02:00
Christoph Lameter
42d623a8cd slub: use irqsafe_cpu_cmpxchg for put_cpu_partial
The cmpxchg must be irq safe. The fallback for this_cpu_cmpxchg only
disables preemption which results in per cpu partial page operation
potentially failing on non x86 platforms.

This patch fixes the following problem reported by Christian Kujau:

  I seem to hit it with heavy disk & cpu IO is in progress on this
  PowerBook
  G4. Full dmesg & .config: http://nerdbynature.de/bits/3.2.0-rc1/oops/

  I've enabled some debug options and now it really points to slub.c:2166

    http://nerdbynature.de/bits/3.2.0-rc1/oops/oops4m.jpg

  With debug options enabled I'm currently in the xmon debugger, not sure
  what to make of it yet, I'll try to get something useful out of it :)

Reported-by: Christian Kujau <lists@nerdbynature.de>
Tested-by: Christian Kujau <lists@nerdbynature.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-11-24 08:44:14 +02:00