Commit Graph

1279 Commits

Author SHA1 Message Date
Linus Torvalds 39cf275a1a Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler changes from Ingo Molnar:
 "The main changes in this cycle are:

   - (much) improved CONFIG_NUMA_BALANCING support from Mel Gorman, Rik
     van Riel, Peter Zijlstra et al.  Yay!

   - optimize preemption counter handling: merge the NEED_RESCHED flag
     into the preempt_count variable, by Peter Zijlstra.

   - wait.h fixes and code reorganization from Peter Zijlstra

   - cfs_bandwidth fixes from Ben Segall

   - SMP load-balancer cleanups from Peter Zijstra

   - idle balancer improvements from Jason Low

   - other fixes and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
  ftrace, sched: Add TRACE_FLAG_PREEMPT_RESCHED
  stop_machine: Fix race between stop_two_cpus() and stop_cpus()
  sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus
  sched: Fix asymmetric scheduling for POWER7
  sched: Move completion code from core.c to completion.c
  sched: Move wait code from core.c to wait.c
  sched: Move wait.c into kernel/sched/
  sched/wait: Fix __wait_event_interruptible_lock_irq_timeout()
  sched: Avoid throttle_cfs_rq() racing with period_timer stopping
  sched: Guarantee new group-entities always have weight
  sched: Fix hrtimer_cancel()/rq->lock deadlock
  sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining
  sched: Fix race on toggling cfs_bandwidth_used
  sched: Remove extra put_online_cpus() inside sched_setaffinity()
  sched/rt: Fix task_tick_rt() comment
  sched/wait: Fix build breakage
  sched/wait: Introduce prepare_to_wait_event()
  sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too
  sched: Remove get_online_cpus() usage
  sched: Fix race in migrate_swap_stop()
  ...
2013-11-12 10:20:12 +09:00
Helge Deller 527973c840 parisc: add kernel audit feature
Implement missing functions for parisc to provide kernel audit feature.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-11-07 22:27:20 +01:00
Eric Paris 83fa6bbe4c audit: remove CONFIG_AUDIT_LOGINUID_IMMUTABLE
After trying to use this feature in Fedora we found the hard coding
policy like this into the kernel was a bad idea.  Surprise surprise.
We ran into these problems because it was impossible to launch a
container as a logged in user and run a login daemon inside that container.
This reverts back to the old behavior before this option was added.  The
option will be re-added in a userspace selectable manor such that
userspace can choose when it is and when it is not appropriate.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2013-11-05 11:08:01 -05:00
Krzysztof Mazur 08746a65c2 init: fix in-place parameter modification regression
Before commit 026cee0086
("params: <level>_initcall-like kernel parameters") the __setup
parameter parsing code could modify parameter in the
static_command_line buffer and such modifications were kept. After
that commit such modifications are destroyed during per-initcall level
parameter parsing because the same static_command_line buffer is used
and only parameters for appropriate initcall level are parsed.

That change broke at least parsing "ubd" parameter in the ubd driver
when the COW file is used.

Now the separate buffer is used for per-initcall parameter parsing.

Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-10-31 13:49:13 +10:30
David S. Miller c3fa32b976 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/qmi_wwan.c
	include/net/dst.h

Trivial merge conflicts, both were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23 16:49:34 -04:00
Hannes Frederic Sowa c4b2c0c5f6 static_key: WARN on usage before jump_label_init was called
Usage of the static key primitives to toggle a branch must not be used
before jump_label_init() is called from init/main.c. jump_label_init
reorganizes and wires up the jump_entries so usage before that could
have unforeseen consequences.

Following primitives are now checked for correct use:
* static_key_slow_inc
* static_key_slow_dec
* static_key_slow_dec_deferred
* jump_label_rate_limit

The x86 architecture already checks this by testing if the default_nop
was already replaced with an optimal nop or with a branch instruction. It
will panic then. Other architectures don't check for this.

Because we need to relax this check for the x86 arch to allow code to
transition from default_nop to the enabled state and other architectures
did not check for this at all this patch introduces checking on the
static_key primitives in a non-arch dependent manner.

All checked functions are considered slow-path so the additional check
does no harm to performance.

The warnings are best observed with earlyprintk.

Based on a patch from Andi Kleen.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-19 19:45:35 -04:00
Paul Gortmaker 6d56a410ae NUMA: fix typos in Kconfig help text
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-10-14 15:58:56 +02:00
Ingo Molnar ec0ad3d01f Merge branch 'core/urgent' into sched/core
Merge in asm goto fix, to be able to apply the asm/rmwcc.h fix.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-11 07:39:37 +02:00
Linus Torvalds f715729ee4 These patches are designed to enable improvements to /dev/random for
non-x86 platforms, in particular MIPS and ARM.
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Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

Pull /dev/random changes from Ted Ts'o:
 "These patches are designed to enable improvements to /dev/random for
  non-x86 platforms, in particular MIPS and ARM"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: allow architectures to optionally define random_get_entropy()
  random: run random_int_secret_init() run after all late_initcalls
2013-10-10 12:31:43 -07:00
Kevin Hilman ff3fb25412 nohz: Drop generic vtime obsolete dependency on CONFIG_64BIT
The CONFIG_64BIT requirement on vtime can finally be removed
since we now depend on HAVE_VIRT_CPU_ACCOUNTING_GEN which
already takes care of the arch ability to handle nsecs based
cputime_t safely.

Signed-off-by: Kevin Hilman <khilman@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Arm Linux <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-09-30 15:37:01 +02:00
Kevin Hilman 554b0004d0 vtime: Add HAVE_VIRT_CPU_ACCOUNTING_GEN Kconfig
With VIRT_CPU_ACCOUNTING_GEN, cputime_t becomes 64-bit. In order
to use that feature, arch code should be audited to ensure there are no
races in concurrent read/write of cputime_t. For example,
reading/writing 64-bit cputime_t on some 32-bit arches may require
multiple accesses for low and high value parts, so proper locking
is needed to protect against concurrent accesses.

Therefore, add CONFIG_HAVE_VIRT_CPU_ACCOUNTING_GEN which arches can
enable after they've been audited for potential races.

This option is automatically enabled on 64-bit platforms.

Feature requested by Frederic Weisbecker.

Signed-off-by: Kevin Hilman <khilman@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Arm Linux <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-09-30 15:35:53 +02:00
David Howells b56e5a17b6 KEYS: Separate the kernel signature checking keyring from module signing
Separate the kernel signature checking keyring from module signing so that it
can be used by code other than the module-signing code.

Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
Peter Zijlstra 4a2b4b2227 sched: Introduce preempt_count accessor functions
Replace the single preempt_count() 'function' that's an lvalue with
two proper functions:

 preempt_count() - returns the preempt_count value as rvalue
 preempt_count_set() - Allows setting the preempt-count value

Also provide preempt_count_ptr() as a convenience wrapper to implement
all modifying operations.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-orxrbycjozopqfhb4dxdkdvb@git.kernel.org
[ Fixed build failure. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25 14:07:32 +02:00
Theodore Ts'o 47d06e532e random: run random_int_secret_init() run after all late_initcalls
The some platforms (e.g., ARM) initializes their clocks as
late_initcalls for some unknown reason.  So make sure
random_int_secret_init() is run after all of the late_initcalls are
run.

Cc: stable@vger.kernel.org
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-09-23 06:35:06 -04:00
Linus Torvalds bff157b3ad Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
Pull SLAB update from Pekka Enberg:
 "Nothing terribly exciting here apart from Christoph's kmalloc
  unification patches that brings sl[aou]b implementations closer to
  each other"

* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  slab: Use correct GFP_DMA constant
  slub: remove verify_mem_not_deleted()
  mm/sl[aou]b: Move kmallocXXX functions to common code
  mm, slab_common: add 'unlikely' to size check of kmalloc_slab()
  mm/slub.c: beautify code for removing redundancy 'break' statement.
  slub: Remove unnecessary page NULL check
  slub: don't use cpu partial pages on UP
  mm/slub: beautify code for 80 column limitation and tab alignment
  mm/slub: remove 'per_cpu' which is useless variable
2013-09-15 07:15:06 -04:00
Rob Landley 6e19eded36 initmpfs: use initramfs if rootfstype= or root= specified
Command line option rootfstype=ramfs to obtain old initramfs behavior, and
use ramfs instead of tmpfs for stub when root= defined (for cosmetic
reasons).

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Rob Landley <rob@landley.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:59:38 -07:00
Rob Landley 16203a7a94 initmpfs: make rootfs use tmpfs when CONFIG_TMPFS enabled
Conditionally call the appropriate fs_init function and fill_super
functions.  Add a use once guard to shmem_init() to simply succeed on a
second call.

(Note that IS_ENABLED() is a compile time constant so dead code
elimination removes unused function calls when CONFIG_TMPFS is disabled.)

Signed-off-by: Rob Landley <rob@landley.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:59:37 -07:00
Rob Landley 57f150a58c initmpfs: move rootfs code from fs/ramfs/ to init/
When the rootfs code was a wrapper around ramfs, having them in the same
file made sense.  Now that it can wrap another filesystem type, move it in
with the init code instead.

This also allows a subsequent patch to access rootfstype= command line
arg.

Signed-off-by: Rob Landley <rob@landley.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:59:37 -07:00
Linus Torvalds 5b4197845a Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kconfig updates from Michal Marek:
 "This is the kconfig part of kbuild for v3.12-rc1:
   - post-3.11 search code fixes and micro-optimizations
   - CONFIG_MODULES is no longer a special case; this is needed to
     eventually fix the bug that using KCONFIG_ALLCONFIG breaks
     allmodconfig
   - long long is used to store hex and int values
   - make silentoldconfig no longer warns when a symbol changes from
     tristate to bool (it's a job for make oldconfig)
   - scripts/diffconfig updated to work with newer Pythons
   - scripts/config does not rely on GNU sed extensions"

* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kconfig: do not allow more than one symbol to have 'option modules'
  kconfig: regenerate bison parser
  kconfig: do not special-case 'MODULES' symbol
  diffconfig: Update script to support python versions 2.5 through 3.3
  diffconfig: Gracefully exit if the default config files are not present
  modules: do not depend on kconfig to set 'modules' option to symbol MODULES
  kconfig: silence warning when parsing auto.conf when a symbol has changed type
  scripts/config: use sed's POSIX interface
  kconfig: switch to "long long" for sanity
  kconfig: simplify symbol-search code
  kconfig: don't allocate n+1 elements in temporary array
  kconfig: minor style fixes in symbol-search code
  kconfig/[mn]conf: shorten title in search-box
  kconfig: avoid multiple calls to strlen
  Documentation/kconfig: more concise and straightforward search explanation
2013-09-11 08:34:25 -07:00
Linus Torvalds 300893b08f xfs: update for v3.12-rc1
For 3.12-rc1 there are a number of bugfixes in addition to work to ease usage
 of shared code between libxfs and the kernel, the rest of the work to enable
 project and group quotas to be used simultaneously, performance optimisations
 in the log and the CIL, directory entry file type support, fixes for log space
 reservations, some spelling/grammar cleanups, and the addition of user
 namespace support.
 
 - introduce readahead to log recovery
 - add directory entry file type support
 - fix a number of spelling errors in comments
 - introduce new Q_XGETQSTATV quotactl for project quotas
 - add USER_NS support
 - log space reservation rework
 - CIL optimisations
 - kernel/userspace libxfs rework
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Merge tag 'xfs-for-linus-v3.12-rc1' of git://oss.sgi.com/xfs/xfs

Pull xfs updates from Ben Myers:
 "For 3.12-rc1 there are a number of bugfixes in addition to work to
  ease usage of shared code between libxfs and the kernel, the rest of
  the work to enable project and group quotas to be used simultaneously,
  performance optimisations in the log and the CIL, directory entry file
  type support, fixes for log space reservations, some spelling/grammar
  cleanups, and the addition of user namespace support.

   - introduce readahead to log recovery
   - add directory entry file type support
   - fix a number of spelling errors in comments
   - introduce new Q_XGETQSTATV quotactl for project quotas
   - add USER_NS support
   - log space reservation rework
   - CIL optimisations
  - kernel/userspace libxfs rework"

* tag 'xfs-for-linus-v3.12-rc1' of git://oss.sgi.com/xfs/xfs: (112 commits)
  xfs: XFS_MOUNT_QUOTA_ALL needed by userspace
  xfs: dtype changed xfs_dir2_sfe_put_ino to xfs_dir3_sfe_put_ino
  Fix wrong flag ASSERT in xfs_attr_shortform_getvalue
  xfs: finish removing IOP_* macros.
  xfs: inode log reservations are too small
  xfs: check correct status variable for xfs_inobt_get_rec() call
  xfs: inode buffers may not be valid during recovery readahead
  xfs: check LSN ordering for v5 superblocks during recovery
  xfs: btree block LSN escaping to disk uninitialised
  XFS: Assertion failed: first <= last && last < BBTOB(bp->b_length), file: fs/xfs/xfs_trans_buf.c, line: 568
  xfs: fix bad dquot buffer size in log recovery readahead
  xfs: don't account buffer cancellation during log recovery readahead
  xfs: check for underflow in xfs_iformat_fork()
  xfs: xfs_dir3_sfe_put_ino can be static
  xfs: introduce object readahead to log recovery
  xfs: Simplify xfs_ail_min() with list_first_entry_or_null()
  xfs: Register hotcpu notifier after initialization
  xfs: add xfs sb v4 support for dirent filetype field
  xfs: Add write support for dirent filetype field
  xfs: Add read-only support for dirent filetype field
  ...
2013-09-09 11:19:09 -07:00
Linus Torvalds 6832d9652f Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers/nohz changes from Ingo Molnar:
 "It mostly contains fixes and full dynticks off-case optimizations, by
  Frederic Weisbecker"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  nohz: Include local CPU in full dynticks global kick
  nohz: Optimize full dynticks's sched hooks with static keys
  nohz: Optimize full dynticks state checks with static keys
  nohz: Rename a few state variables
  vtime: Always debug check snapshot source _before_ updating it
  vtime: Always scale generic vtime accounting results
  vtime: Optimize full dynticks accounting off case with static keys
  vtime: Describe overriden functions in dedicated arch headers
  m68k: hardirq_count() only need preempt_mask.h
  hardirq: Split preempt count mask definitions
  context_tracking: Split low level state headers
  vtime: Fix racy cputime delta update
  vtime: Remove a few unneeded generic vtime state checks
  context_tracking: User/kernel broundary cross trace events
  context_tracking: Optimize context switch off case with static keys
  context_tracking: Optimize guest APIs off case with static key
  context_tracking: Optimize main APIs off case with static key
  context_tracking: Ground setup for static key use
  context_tracking: Remove full dynticks' hacky dependency on wide context tracking
  nohz: Only enable context tracking on full dynticks CPUs
  ...
2013-09-04 09:36:54 -07:00
Ingo Molnar 7d992feb76 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

"
 * Update RCU documentation.  These were posted to LKML at
   https://lkml.org/lkml/2013/8/19/611.

 * Miscellaneous fixes.  These were posted to LKML at
   https://lkml.org/lkml/2013/8/19/619.

 * Full-system idle detection.  This is for use by Frederic
   Weisbecker's adaptive-ticks mechanism.  Its purpose is
   to allow the timekeeping CPU to shut off its tick when
   all other CPUs are idle.  These were posted to LKML at
   https://lkml.org/lkml/2013/8/19/648.

 * Improve rcutorture test coverage.  These were posted to LKML at
   https://lkml.org/lkml/2013/8/19/675.
"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-03 07:41:11 +02:00
Michal Hocko 07555ac144 memcg: get rid of swapaccount leftovers
The swapaccount kernel parameter without any values has been removed by
commit a2c8990aed ("memsw: remove noswapaccount kernel parameter") but
it seems that we didn't get rid of all the left overs.

Make sure that menuconfig help text and kernel-parameters.txt are clear
about value for the paramter and remove the stalled comment which is not
very much useful on its own.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reported-by: Gergely Risko <gergely@risko.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-23 09:51:22 -07:00
James Hogan 5361471437 rcu: Select IRQ_WORK from TREE_PREEMPT_RCU
TREE_RCU and TREE_PREEMPT_RCU both cause kernel/rcutree.c to be built,
but only TREE_RCU selects IRQ_WORK, which can result in an undefined
reference to irq_work_queue for some (random) configs:

kernel/built-in.o In function `rcu_start_gp_advanced':
kernel/rcutree.c:1564: undefined reference to `irq_work_queue'

Select IRQ_WORK from TREE_PREEMPT_RCU too to fix this.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-08-18 17:40:25 -07:00
Yann E. MORIN 11097a0367 modules: do not depend on kconfig to set 'modules' option to symbol MODULES
Currently, the MODULES symbol is special-cased in different places in the
kconfig language. For example, if no symbol is defined to enable tristates,
then kconfig looks up for a symbol named 'MODULES', and forces the 'modules'
option onto that symbol.

This causes problems as such:
  - since MODULES is special-cased, reading the configuration with
    KCONFIG_ALLCONFIG set will forcibly set MODULES to be 'valid' (ie.
    it has a valid value), when no such value was previously set. So
    MODULES defaults to 'n' unless it is present in KCONFIG_ALLCONFIG
  - other third-party projects may decide that 'MODULES' plays a different
    role for them

This has been exposed by cset #cfa98f2e:
    kconfig: do not override symbols already set
and reported by Stephen in:
    http://marc.info/?l=linux-next&m=137592137915234&w=2

As suggested by Sam, we explicitly define the MODULES symbol to be the
tristate-enabler. This will allow us to drop special-casing of MODULES
in the kconfig language, later.

(Note: this patch is not a fix to Stephen's issue, just a first step).

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: yann.morin.1998@free.fr
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: sedat.dilek@gmail.com
Cc: Theodore Ts'o <tytso@mit.edu>
2013-08-15 22:56:08 +02:00
Dwight Engen d6970d4b72 enable building user namespace with xfs
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-08-15 14:27:22 -05:00
Frederic Weisbecker 65f382fd0c context_tracking: Ground setup for static key use
Prepare for using a static key in the context tracking subsystem.
This will help optimizing the off case on its many users:

* user_enter, user_exit, exception_enter, exception_exit, guest_enter,
  guest_exit, vtime_*()

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14 17:12:46 +02:00
Uwe Kleine-König b39ffbf8b1 slub: don't use cpu partial pages on UP
cpu partial pages are used to avoid contention which does not exist in
the UP case. So let SLUB_CPU_PARTIAL depend on SMP.

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2013-08-13 09:21:45 +03:00
Frederic Weisbecker d84d27a491 context_tracking: Remove full dynticks' hacky dependency on wide context tracking
Now that the full dynticks subsystem only enables the context tracking
on full dynticks CPUs, lets remove the dependency on CONTEXT_TRACKING_FORCE

This dependency was a hack to enable the context tracking widely for the
full dynticks susbsystem until the latter becomes able to enable it in a
more CPU-finegrained fashion.

Now CONTEXT_TRACKING_FORCE only stands for testing on archs that
work on support for the context tracking while full dynticks can't be
used yet due to unmet dependencies. It simulates a system where all CPUs
are full dynticks so that RCU user extended quiescent states and dynticks
cputime accounting can be tested on the given arch.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13 00:54:34 +02:00
Paul Gortmaker 0db0628d90 kernel: delete __cpuinit usage from all core kernel files
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the uses of the __cpuinit macros from C files in
the core kernel directories (kernel, init, lib, mm, and include)
that don't really have a specific maintainer.

[1] https://lkml.org/lkml/2013/5/20/589

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:59 -04:00
Linus Torvalds 54be820019 Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
Pull slab update from Pekka Enberg:
 "Highlights:

  - Fix for boot-time problems on some architectures due to
    init_lock_keys() not respecting kmalloc_caches boundaries
    (Christoph Lameter)

  - CONFIG_SLUB_CPU_PARTIAL requested by RT folks (Joonsoo Kim)

  - Fix for excessive slab freelist draining (Wanpeng Li)

  - SLUB and SLOB cleanups and fixes (various people)"

I ended up editing the branch, and this avoids two commits at the end
that were immediately reverted, and I instead just applied the oneliner
fix in between myself.

* 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
  slub: Check for page NULL before doing the node_match check
  mm/slab: Give s_next and s_stop slab-specific names
  slob: Check for NULL pointer before calling ctor()
  slub: Make cpu partial slab support configurable
  slab: add kmalloc() to kernel API documentation
  slab: fix init_lock_keys
  slob: use DIV_ROUND_UP where possible
  slub: do not put a slab to cpu partial list when cpu_partial is 0
  mm/slub: Use node_nr_slabs and node_nr_objs in get_slabinfo
  mm/slub: Drop unnecessary nr_partials
  mm/slab: Fix /proc/slabinfo unwriteable for slab
  mm/slab: Sharing s_next and s_stop between slab and slub
  mm/slab: Fix drain freelist excessively
  slob: Rework #ifdeffery in slab.h
  mm, slab: moved kmem_cache_alloc_node comment to correct place
2013-07-14 15:14:29 -07:00
Kyungsik Lee e76e1fdfa8 lib: add support for LZ4-compressed kernel
Add support for extracting LZ4-compressed kernel images, as well as
LZ4-compressed ramdisk images in the kernel boot process.

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Joonsoo Kim 345c905d13 slub: Make cpu partial slab support configurable
CPU partial support can introduce level of indeterminism that is not
wanted in certain context (like a realtime kernel). Make it
configurable.

This patch is based on Christoph Lameter's "slub: Make cpu partial slab
support configurable V2".

Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2013-07-07 19:09:56 +03:00
Linus Torvalds 21884a83b2 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer core updates from Thomas Gleixner:
 "The timer changes contain:

   - posix timer code consolidation and fixes for odd corner cases

   - sched_clock implementation moved from ARM to core code to avoid
     duplication by other architectures

   - alarm timer updates

   - clocksource and clockevents unregistration facilities

   - clocksource/events support for new hardware

   - precise nanoseconds RTC readout (Xen feature)

   - generic support for Xen suspend/resume oddities

   - the usual lot of fixes and cleanups all over the place

  The parts which touch other areas (ARM/XEN) have been coordinated with
  the relevant maintainers.  Though this results in an handful of
  trivial to solve merge conflicts, which we preferred over nasty cross
  tree merge dependencies.

  The patches which have been committed in the last few days are bug
  fixes plus the posix timer lot.  The latter was in akpms queue and
  next for quite some time; they just got forgotten and Frederic
  collected them last minute."

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits)
  hrtimer: Remove unused variable
  hrtimers: Move SMP function call to thread context
  clocksource: Reselect clocksource when watchdog validated high-res capability
  posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting
  posix_timers: fix racy timer delta caching on task exit
  posix-timers: correctly get dying task time sample in posix_cpu_timer_schedule()
  selftests: add basic posix timers selftests
  posix_cpu_timers: consolidate expired timers check
  posix_cpu_timers: consolidate timer list cleanups
  posix_cpu_timer: consolidate expiry time type
  tick: Sanitize broadcast control logic
  tick: Prevent uncontrolled switch to oneshot mode
  tick: Make oneshot broadcast robust vs. CPU offlining
  x86: xen: Sync the CMOS RTC as well as the Xen wallclock
  x86: xen: Sync the wallclock when the system time is set
  timekeeping: Indicate that clock was set in the pvclock gtod notifier
  timekeeping: Pass flags instead of multiple bools to timekeeping_update()
  xen: Remove clock_was_set() call in the resume path
  hrtimers: Support resuming with two or more CPUs online (but stopped)
  timer: Fix jiffies wrap behavior of round_jiffies_common()
  ...
2013-07-06 14:09:38 -07:00
Thomas Gleixner 2b0f89317e Merge branch 'timers/posix-cpu-timers-for-tglx' of
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/core

Frederic sayed: "Most of these patches have been hanging around for
several month now, in -mmotm for a significant chunk. They already
missed a few releases."

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-07-04 23:11:22 +02:00
Toralf Förster ca75b4d879 insert missing space in printk line of root_delay
Trivial, but it really looks better.

Signed-off-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:45 -07:00
Steven Rostedt ff1c8fac88 init: remove permanent string buffer from do_one_initcall()
do_one_initcall() uses a 64 byte string buffer to save a message. This
buffer is declared static and is only used at boot up and when a module
is loaded. As 64 bytes is very small, and this function has very limited
scope, there's no reason to waste permanent memory with this string and
not just simply put it on the stack.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:45 -07:00
Sergey Dyasly f60e2a968e memcg: Kconfig info update
Now there are only 2 members in struct page_cgroup.  Update config MEMCG
description accordingly.

Signed-off-by: Sergey Dyasly <dserrg@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:34 -07:00
Linus Torvalds f0bb4c0ab0 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Kernel improvements:

   - watchdog driver improvements by Li Zefan
   - Power7 CPI stack events related improvements by Sukadev Bhattiprolu
   - event multiplexing via hrtimers and other improvements by Stephane
     Eranian
   - kernel stack use optimization by Andrew Hunter
   - AMD IOMMU uncore PMU support by Suravee Suthikulpanit
   - NMI handling rate-limits by Dave Hansen
   - various hw_breakpoint fixes by Oleg Nesterov
   - hw_breakpoint overflow period sampling and related signal handling
     fixes by Jiri Olsa
   - Intel Haswell PMU support by Andi Kleen

  Tooling improvements:

   - Reset SIGTERM handler in workload child process, fix from David
     Ahern.
   - Makefile reorganization, prep work for Kconfig patches, from Jiri
     Olsa.
   - Add automated make test suite, from Jiri Olsa.
   - Add --percent-limit option to 'top' and 'report', from Namhyung
     Kim.
   - Sorting improvements, from Namhyung Kim.
   - Expand definition of sysfs format attribute, from Michael Ellerman.

  Tooling fixes:

   - 'perf tests' fixes from Jiri Olsa.
   - Make Power7 CPI stack events available in sysfs, from Sukadev
     Bhattiprolu.
   - Handle death by SIGTERM in 'perf record', fix from David Ahern.
   - Fix printing of perf_event_paranoid message, from David Ahern.
   - Handle realloc failures in 'perf kvm', from David Ahern.
   - Fix divide by 0 in variance, from David Ahern.
   - Save parent pid in thread struct, from David Ahern.
   - Handle JITed code in shared memory, from Andi Kleen.
   - Fixes for 'perf diff', from Jiri Olsa.
   - Remove some unused struct members, from Jiri Olsa.
   - Add missing liblk.a dependency for python/perf.so, fix from Jiri
     Olsa.
   - Respect CROSS_COMPILE in liblk.a, from Rabin Vincent.
   - No need to do locking when adding hists in perf report, only 'top'
     needs that, from Namhyung Kim.
   - Fix alignment of symbol column in in the hists browser (top,
     report) when -v is given, from NAmhyung Kim.
   - Fix 'perf top' -E option behavior, from Namhyung Kim.
   - Fix bug in isupper() and islower(), from Sukadev Bhattiprolu.
   - Fix compile errors in bp_signal 'perf test', from Sukadev
     Bhattiprolu.

  ... and more things"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (102 commits)
  perf/x86: Disable PEBS-LL in intel_pmu_pebs_disable()
  perf/x86: Fix shared register mutual exclusion enforcement
  perf/x86/intel: Support full width counting
  x86: Add NMI duration tracepoints
  perf: Drop sample rate when sampling is too slow
  x86: Warn when NMI handlers take large amounts of time
  hw_breakpoint: Introduce "struct bp_cpuinfo"
  hw_breakpoint: Simplify *register_wide_hw_breakpoint()
  hw_breakpoint: Introduce cpumask_of_bp()
  hw_breakpoint: Simplify the "weight" usage in toggle_bp_slot() paths
  hw_breakpoint: Simplify list/idx mess in toggle_bp_slot() paths
  perf/x86/intel: Add mem-loads/stores support for Haswell
  perf/x86/intel: Support Haswell/v4 LBR format
  perf/x86/intel: Move NMI clearing to end of PMI handler
  perf/x86/intel: Add Haswell PEBS support
  perf/x86/intel: Add simple Haswell PMU support
  perf/x86/intel: Add Haswell PEBS record support
  perf/x86/intel: Fix sparse warning
  perf/x86/amd: AMD IOMMU Performance Counter PERF uncore PMU implementation
  perf/x86/amd: Add IOMMU Performance Counter resource management
  ...
2013-07-02 16:15:23 -07:00
Linus Torvalds ab3d681e9d Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The major changes:

  - Simplify RCU's grace-period and callback processing based on the new
    numbering for callbacks.

  - Removal of TINY_PREEMPT_RCU in favor of TREE_PREEMPT_RCU for
    single-CPU low-latency systems.

  - SRCU-related changes and fixes.

  - Miscellaneous fixes, including converting a few remaining printk()
    calls to pr_*().

  - Documentation updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  rcu: Shrink TINY_RCU by reworking CPU-stall ifdefs
  rcu: Shrink TINY_RCU by moving exit_rcu()
  rcu: Remove TINY_PREEMPT_RCU tracing documentation
  rcu: Consolidate rcutiny_plugin.h ifdefs
  rcu: Remove rcu_preempt_note_context_switch()
  rcu: Remove the CONFIG_TINY_RCU ifdefs in rcutiny.h
  rcu: Remove check_cpu_stall_preempt()
  rcu: Simplify RCU_TINY RCU callback invocation
  rcu: Remove rcu_preempt_process_callbacks()
  rcu: Remove rcu_preempt_remove_callbacks()
  rcu: Remove rcu_preempt_check_callbacks()
  rcu: Remove show_tiny_preempt_stats()
  rcu: Remove TINY_PREEMPT_RCU
  powerpc,kvm: fix imbalance srcu_read_[un]lock()
  rcu: Remove srcu_read_lock_raw() and srcu_read_unlock_raw().
  rcu: Apply Dave Jones's NOCB Kconfig help feedback
  rcu: Merge adjacent identical ifdefs
  rcu: Drive quiescent-state-forcing delay from HZ
  rcu: Remove "Experimental" flags
  kthread: Add kworker kthreads to OS-jitter documentation
  ...
2013-07-02 16:13:29 -07:00
Jiri Slaby 4bb1667255 build some drivers only when compile-testing
Some drivers can be built on more platforms than they run on. This is
a burden for users and distributors who package a kernel. They have to
manually deselect some (for them useless) drivers when updating their
configs via oldconfig. And yet, sometimes it is even impossible to
disable the drivers without patching the kernel.

Introduce a new config option COMPILE_TEST and make all those drivers
to depend on the platform they run on, or on the COMPILE_TEST option.
Now, when users/distributors choose COMPILE_TEST=n they will not have
the drivers in their allmodconfig setups, but developers still can
compile-test them with COMPILE_TEST=y.

Now the drivers where we use this new option:
* PTP_1588_CLOCK_PCH: The PCH EG20T is only compatible with Intel Atom
  processors so it should depend on x86.
* FB_GEODE: Geode is 32-bit only so only enable it for X86_32.
* USB_CHIPIDEA_IMX: The OF_DEVICE dependency will be met on powerpc
  systems -- which do not actually support the hardware via that
  method.
* INTEL_MID_PTI: It is specific to the Penwell type of Intel Atom
  device.

[v2]
* remove EXPERT dependency

[gregkh - remove chipidea portion, as it's incorrect, and also doesn't
 apply to my driver-core tree]

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: linux-usb@vger.kernel.org
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: linux-geode@lists.infradead.org
Cc: linux-fbdev@vger.kernel.org
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: netdev@vger.kernel.org
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: "Keller, Jacob E" <jacob.e.keller@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-24 16:41:32 -07:00
Greg Kroah-Hartman bb07b00be7 Merge 3.10-rc6 into driver-core-next
We want these fixes here too.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 16:57:20 -07:00
Stephen Boyd 38ff87f77a sched_clock: Make ARM's sched_clock generic for all architectures
Nothing about the sched_clock implementation in the ARM port is
specific to the architecture. Generalize the code so that other
architectures can use it by selecting GENERIC_SCHED_CLOCK.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[jstultz: Merge minor collisions with other patches in my tree]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-06-12 14:02:13 -07:00
Paul E. McKenney be77f87c00 Merge branches 'cbnum.2013.06.10a', 'doc.2013.06.10a', 'fixes.2013.06.10a', 'srcu.2013.06.10a' and 'tiny.2013.06.10a' into HEAD
cbnum.2013.06.10a: Apply simplifications stemming from the new callback
	numbering.

doc.2013.06.10a: Documentation updates.

fixes.2013.06.10a: Miscellaneous fixes.

srcu.2013.06.10a: Updates to SRCU.

tiny.2013.06.10a: Eliminate TINY_PREEMPT_RCU.
2013-06-10 13:46:44 -07:00
Paul E. McKenney 127781d1ba rcu: Remove TINY_PREEMPT_RCU
TINY_PREEMPT_RCU adds significant code and complexity, but does not
offer commensurate benefits.  People currently using TINY_PREEMPT_RCU
can get much better memory footprint with TINY_RCU, or, if they really
need preemptible RCU, they can use TREE_PREEMPT_RCU with a relatively
minor degradation in memory footprint.  Please note that this move
has been widely publicized on LKML (https://lkml.org/lkml/2012/11/12/545)
and on LWN (http://lwn.net/Articles/541037/).

This commit therefore removes TINY_PREEMPT_RCU.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Updated to eliminate #else in rcutiny.h as suggested by Josh ]
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-06-10 13:45:49 -07:00
Paul E. McKenney 676c3dc203 rcu: Apply Dave Jones's NOCB Kconfig help feedback
The Kconfig help text for the RCU_NOCB_CPU_NONE, RCU_NOCB_CPU_ZERO,
and RCU_NOCB_CPU_ALL Kconfig options was unclear, so this commit
adds a bit more detail.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-06-10 13:44:57 -07:00
Paul E. McKenney 9a5739d73f rcu: Remove "Experimental" flags
After a release or two, features are no longer experimental.  Therefore,
this commit removes the "Experimental" tag from them.

Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-06-10 13:44:56 -07:00
Steven Rostedt 016a8d5be6 rcu: Don't call wakeup() with rcu_node structure ->lock held
This commit fixes a lockdep-detected deadlock by moving a wake_up()
call out from a rnp->lock critical section.  Please see below for
the long version of this story.

On Tue, 2013-05-28 at 16:13 -0400, Dave Jones wrote:

> [12572.705832] ======================================================
> [12572.750317] [ INFO: possible circular locking dependency detected ]
> [12572.796978] 3.10.0-rc3+ #39 Not tainted
> [12572.833381] -------------------------------------------------------
> [12572.862233] trinity-child17/31341 is trying to acquire lock:
> [12572.870390]  (rcu_node_0){..-.-.}, at: [<ffffffff811054ff>] rcu_read_unlock_special+0x9f/0x4c0
> [12572.878859]
> but task is already holding lock:
> [12572.894894]  (&ctx->lock){-.-...}, at: [<ffffffff811390ed>] perf_lock_task_context+0x7d/0x2d0
> [12572.903381]
> which lock already depends on the new lock.
>
> [12572.927541]
> the existing dependency chain (in reverse order) is:
> [12572.943736]
> -> #4 (&ctx->lock){-.-...}:
> [12572.960032]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12572.968337]        [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12572.976633]        [<ffffffff8113c987>] __perf_event_task_sched_out+0x2e7/0x5e0
> [12572.984969]        [<ffffffff81088953>] perf_event_task_sched_out+0x93/0xa0
> [12572.993326]        [<ffffffff816ea0bf>] __schedule+0x2cf/0x9c0
> [12573.001652]        [<ffffffff816eacfe>] schedule_user+0x2e/0x70
> [12573.009998]        [<ffffffff816ecd64>] retint_careful+0x12/0x2e
> [12573.018321]
> -> #3 (&rq->lock){-.-.-.}:
> [12573.034628]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.042930]        [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12573.051248]        [<ffffffff8108e6a7>] wake_up_new_task+0xb7/0x260
> [12573.059579]        [<ffffffff810492f5>] do_fork+0x105/0x470
> [12573.067880]        [<ffffffff81049686>] kernel_thread+0x26/0x30
> [12573.076202]        [<ffffffff816cee63>] rest_init+0x23/0x140
> [12573.084508]        [<ffffffff81ed8e1f>] start_kernel+0x3f1/0x3fe
> [12573.092852]        [<ffffffff81ed856f>] x86_64_start_reservations+0x2a/0x2c
> [12573.101233]        [<ffffffff81ed863d>] x86_64_start_kernel+0xcc/0xcf
> [12573.109528]
> -> #2 (&p->pi_lock){-.-.-.}:
> [12573.125675]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.133829]        [<ffffffff816ebe9b>] _raw_spin_lock_irqsave+0x4b/0x90
> [12573.141964]        [<ffffffff8108e881>] try_to_wake_up+0x31/0x320
> [12573.150065]        [<ffffffff8108ebe2>] default_wake_function+0x12/0x20
> [12573.158151]        [<ffffffff8107bbf8>] autoremove_wake_function+0x18/0x40
> [12573.166195]        [<ffffffff81085398>] __wake_up_common+0x58/0x90
> [12573.174215]        [<ffffffff81086909>] __wake_up+0x39/0x50
> [12573.182146]        [<ffffffff810fc3da>] rcu_start_gp_advanced.isra.11+0x4a/0x50
> [12573.190119]        [<ffffffff810fdb09>] rcu_start_future_gp+0x1c9/0x1f0
> [12573.198023]        [<ffffffff810fe2c4>] rcu_nocb_kthread+0x114/0x930
> [12573.205860]        [<ffffffff8107a91d>] kthread+0xed/0x100
> [12573.213656]        [<ffffffff816f4b1c>] ret_from_fork+0x7c/0xb0
> [12573.221379]
> -> #1 (&rsp->gp_wq){..-.-.}:
> [12573.236329]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.243783]        [<ffffffff816ebe9b>] _raw_spin_lock_irqsave+0x4b/0x90
> [12573.251178]        [<ffffffff810868f3>] __wake_up+0x23/0x50
> [12573.258505]        [<ffffffff810fc3da>] rcu_start_gp_advanced.isra.11+0x4a/0x50
> [12573.265891]        [<ffffffff810fdb09>] rcu_start_future_gp+0x1c9/0x1f0
> [12573.273248]        [<ffffffff810fe2c4>] rcu_nocb_kthread+0x114/0x930
> [12573.280564]        [<ffffffff8107a91d>] kthread+0xed/0x100
> [12573.287807]        [<ffffffff816f4b1c>] ret_from_fork+0x7c/0xb0

Notice the above call chain.

rcu_start_future_gp() is called with the rnp->lock held. Then it calls
rcu_start_gp_advance, which does a wakeup.

You can't do wakeups while holding the rnp->lock, as that would mean
that you could not do a rcu_read_unlock() while holding the rq lock, or
any lock that was taken while holding the rq lock. This is because...
(See below).

> [12573.295067]
> -> #0 (rcu_node_0){..-.-.}:
> [12573.309293]        [<ffffffff810b8d36>] __lock_acquire+0x1786/0x1af0
> [12573.316568]        [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.323825]        [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12573.331081]        [<ffffffff811054ff>] rcu_read_unlock_special+0x9f/0x4c0
> [12573.338377]        [<ffffffff810760a6>] __rcu_read_unlock+0x96/0xa0
> [12573.345648]        [<ffffffff811391b3>] perf_lock_task_context+0x143/0x2d0
> [12573.352942]        [<ffffffff8113938e>] find_get_context+0x4e/0x1f0
> [12573.360211]        [<ffffffff811403f4>] SYSC_perf_event_open+0x514/0xbd0
> [12573.367514]        [<ffffffff81140e49>] SyS_perf_event_open+0x9/0x10
> [12573.374816]        [<ffffffff816f4dd4>] tracesys+0xdd/0xe2

Notice the above trace.

perf took its own ctx->lock, which can be taken while holding the rq
lock. While holding this lock, it did a rcu_read_unlock(). The
perf_lock_task_context() basically looks like:

rcu_read_lock();
raw_spin_lock(ctx->lock);
rcu_read_unlock();

Now, what looks to have happened, is that we scheduled after taking that
first rcu_read_lock() but before taking the spin lock. When we scheduled
back in and took the ctx->lock, the following rcu_read_unlock()
triggered the "special" code.

The rcu_read_unlock_special() takes the rnp->lock, which gives us a
possible deadlock scenario.

	CPU0		CPU1		CPU2
	----		----		----

				     rcu_nocb_kthread()
    lock(rq->lock);
		    lock(ctx->lock);
				     lock(rnp->lock);

				     wake_up();

				     lock(rq->lock);

		    rcu_read_unlock();

		    rcu_read_unlock_special();

		    lock(rnp->lock);
    lock(ctx->lock);

**** DEADLOCK ****

> [12573.382068]
> other info that might help us debug this:
>
> [12573.403229] Chain exists of:
>   rcu_node_0 --> &rq->lock --> &ctx->lock
>
> [12573.424471]  Possible unsafe locking scenario:
>
> [12573.438499]        CPU0                    CPU1
> [12573.445599]        ----                    ----
> [12573.452691]   lock(&ctx->lock);
> [12573.459799]                                lock(&rq->lock);
> [12573.467010]                                lock(&ctx->lock);
> [12573.474192]   lock(rcu_node_0);
> [12573.481262]
>  *** DEADLOCK ***
>
> [12573.501931] 1 lock held by trinity-child17/31341:
> [12573.508990]  #0:  (&ctx->lock){-.-...}, at: [<ffffffff811390ed>] perf_lock_task_context+0x7d/0x2d0
> [12573.516475]
> stack backtrace:
> [12573.530395] CPU: 1 PID: 31341 Comm: trinity-child17 Not tainted 3.10.0-rc3+ #39
> [12573.545357]  ffffffff825b4f90 ffff880219f1dbc0 ffffffff816e375b ffff880219f1dc00
> [12573.552868]  ffffffff816dfa5d ffff880219f1dc50 ffff88023ce4d1f8 ffff88023ce4ca40
> [12573.560353]  0000000000000001 0000000000000001 ffff88023ce4d1f8 ffff880219f1dcc0
> [12573.567856] Call Trace:
> [12573.575011]  [<ffffffff816e375b>] dump_stack+0x19/0x1b
> [12573.582284]  [<ffffffff816dfa5d>] print_circular_bug+0x200/0x20f
> [12573.589637]  [<ffffffff810b8d36>] __lock_acquire+0x1786/0x1af0
> [12573.596982]  [<ffffffff810918f5>] ? sched_clock_cpu+0xb5/0x100
> [12573.604344]  [<ffffffff810b9851>] lock_acquire+0x91/0x1f0
> [12573.611652]  [<ffffffff811054ff>] ? rcu_read_unlock_special+0x9f/0x4c0
> [12573.619030]  [<ffffffff816ebc90>] _raw_spin_lock+0x40/0x80
> [12573.626331]  [<ffffffff811054ff>] ? rcu_read_unlock_special+0x9f/0x4c0
> [12573.633671]  [<ffffffff811054ff>] rcu_read_unlock_special+0x9f/0x4c0
> [12573.640992]  [<ffffffff811390ed>] ? perf_lock_task_context+0x7d/0x2d0
> [12573.648330]  [<ffffffff810b429e>] ? put_lock_stats.isra.29+0xe/0x40
> [12573.655662]  [<ffffffff813095a0>] ? delay_tsc+0x90/0xe0
> [12573.662964]  [<ffffffff810760a6>] __rcu_read_unlock+0x96/0xa0
> [12573.670276]  [<ffffffff811391b3>] perf_lock_task_context+0x143/0x2d0
> [12573.677622]  [<ffffffff81139070>] ? __perf_event_enable+0x370/0x370
> [12573.684981]  [<ffffffff8113938e>] find_get_context+0x4e/0x1f0
> [12573.692358]  [<ffffffff811403f4>] SYSC_perf_event_open+0x514/0xbd0
> [12573.699753]  [<ffffffff8108cd9d>] ? get_parent_ip+0xd/0x50
> [12573.707135]  [<ffffffff810b71fd>] ? trace_hardirqs_on_caller+0xfd/0x1c0
> [12573.714599]  [<ffffffff81140e49>] SyS_perf_event_open+0x9/0x10
> [12573.721996]  [<ffffffff816f4dd4>] tracesys+0xdd/0xe2

This commit delays the wakeup via irq_work(), which is what
perf and ftrace use to perform wakeups in critical sections.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-06-10 13:37:11 -07:00
Stephen Rothwell 40b313608a Finally eradicate CONFIG_HOTPLUG
Ever since commit 45f035ab9b ("CONFIG_HOTPLUG should be always on"),
it has been basically impossible to build a kernel with CONFIG_HOTPLUG
turned off.  Remove all the remaining references to it.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 14:20:18 -07:00
Stephane Eranian 9e6302056f perf: Use hrtimers for event multiplexing
The current scheme of using the timer tick was fine for per-thread
events. However, it was causing bias issues in system-wide mode
(including for uncore PMUs). Event groups would not get their fair
share of runtime on the PMU. With tickless kernels, if a core is idle
there is no timer tick, and thus no event rotation (multiplexing).
However, there are events (especially uncore events) which do count
even though cores are asleep.

This patch changes the timer source for multiplexing.  It introduces a
per-PMU per-cpu hrtimer. The advantage is that even when a core goes
idle, it will come back to service the hrtimer, thus multiplexing on
system-wide events works much better.

The per-PMU implementation (suggested by PeterZ) enables adjusting the
multiplexing interval per PMU. The preferred interval is stashed into
the struct pmu. If not set, it will be forced to the default interval
value.

In order to minimize the impact of the hrtimer, it is turned on and
off on demand. When the PMU on a CPU is overcommited, the hrtimer is
activated.  It is stopped when the PMU is not overcommitted.

In order for this to work properly, we had to change the order of
initialization in start_kernel() such that hrtimer_init() is run
before perf_event_init().

The default interval in milliseconds is set to a timer tick just like
with the old code. We will provide a sysctl to tune this in another
patch.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1364991694-5876-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-28 09:07:10 +02:00
Linus Torvalds 534c97b095 Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull 'full dynticks' support from Ingo Molnar:
 "This tree from Frederic Weisbecker adds a new, (exciting! :-) core
  kernel feature to the timer and scheduler subsystems: 'full dynticks',
  or CONFIG_NO_HZ_FULL=y.

  This feature extends the nohz variable-size timer tick feature from
  idle to busy CPUs (running at most one task) as well, potentially
  reducing the number of timer interrupts significantly.

  This feature got motivated by real-time folks and the -rt tree, but
  the general utility and motivation of full-dynticks runs wider than
  that:

   - HPC workloads get faster: CPUs running a single task should be able
     to utilize a maximum amount of CPU power.  A periodic timer tick at
     HZ=1000 can cause a constant overhead of up to 1.0%.  This feature
     removes that overhead - and speeds up the system by 0.5%-1.0% on
     typical distro configs even on modern systems.

   - Real-time workload latency reduction: CPUs running critical tasks
     should experience as little jitter as possible.  The last remaining
     source of kernel-related jitter was the periodic timer tick.

   - A single task executing on a CPU is a pretty common situation,
     especially with an increasing number of cores/CPUs, so this feature
     helps desktop and mobile workloads as well.

  The cost of the feature is mainly related to increased timer
  reprogramming overhead when a CPU switches its tick period, and thus
  slightly longer to-idle and from-idle latency.

  Configuration-wise a third mode of operation is added to the existing
  two NOHZ kconfig modes:

   - CONFIG_HZ_PERIODIC: [formerly !CONFIG_NO_HZ], now explicitly named
     as a config option.  This is the traditional Linux periodic tick
     design: there's a HZ tick going on all the time, regardless of
     whether a CPU is idle or not.

   - CONFIG_NO_HZ_IDLE: [formerly CONFIG_NO_HZ=y], this turns off the
     periodic tick when a CPU enters idle mode.

   - CONFIG_NO_HZ_FULL: this new mode, in addition to turning off the
     tick when a CPU is idle, also slows the tick down to 1 Hz (one
     timer interrupt per second) when only a single task is running on a
     CPU.

  The .config behavior is compatible: existing !CONFIG_NO_HZ and
  CONFIG_NO_HZ=y settings get translated to the new values, without the
  user having to configure anything.  CONFIG_NO_HZ_FULL is turned off by
  default.

  This feature is based on a lot of infrastructure work that has been
  steadily going upstream in the last 2-3 cycles: related RCU support
  and non-periodic cputime support in particular is upstream already.

  This tree adds the final pieces and activates the feature.  The pull
  request is marked RFC because:

   - it's marked 64-bit only at the moment - the 32-bit support patch is
     small but did not get ready in time.

   - it has a number of fresh commits that came in after the merge
     window.  The overwhelming majority of commits are from before the
     merge window, but still some aspects of the tree are fresh and so I
     marked it RFC.

   - it's a pretty wide-reaching feature with lots of effects - and
     while the components have been in testing for some time, the full
     combination is still not very widely used.  That it's default-off
     should reduce its regression abilities and obviously there are no
     known regressions with CONFIG_NO_HZ_FULL=y enabled either.

   - the feature is not completely idempotent: there is no 100%
     equivalent replacement for a periodic scheduler/timer tick.  In
     particular there's ongoing work to map out and reduce its effects
     on scheduler load-balancing and statistics.  This should not impact
     correctness though, there are no known regressions related to this
     feature at this point.

   - it's a pretty ambitious feature that with time will likely be
     enabled by most Linux distros, and we'd like you to make input on
     its design/implementation, if you dislike some aspect we missed.
     Without flaming us to crisp! :-)

  Future plans:

   - there's ongoing work to reduce 1Hz to 0Hz, to essentially shut off
     the periodic tick altogether when there's a single busy task on a
     CPU.  We'd first like 1 Hz to be exposed more widely before we go
     for the 0 Hz target though.

   - once we reach 0 Hz we can remove the periodic tick assumption from
     nr_running>=2 as well, by essentially interrupting busy tasks only
     as frequently as the sched_latency constraints require us to do -
     once every 4-40 msecs, depending on nr_running.

  I am personally leaning towards biting the bullet and doing this in
  v3.10, like the -rt tree this effort has been going on for too long -
  but the final word is up to you as usual.

  More technical details can be found in Documentation/timers/NO_HZ.txt"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  sched: Keep at least 1 tick per second for active dynticks tasks
  rcu: Fix full dynticks' dependency on wide RCU nocb mode
  nohz: Protect smp_processor_id() in tick_nohz_task_switch()
  nohz_full: Add documentation.
  cputime_nsecs: use math64.h for nsec resolution conversion helpers
  nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config
  nohz: Reduce overhead under high-freq idling patterns
  nohz: Remove full dynticks' superfluous dependency on RCU tree
  nohz: Fix unavailable tick_stop tracepoint in dynticks idle
  nohz: Add basic tracing
  nohz: Select wide RCU nocb for full dynticks
  nohz: Disable the tick when irq resume in full dynticks CPU
  nohz: Re-evaluate the tick for the new task after a context switch
  nohz: Prepare to stop the tick on irq exit
  nohz: Implement full dynticks kick
  nohz: Re-evaluate the tick from the scheduler IPI
  sched: New helper to prevent from stopping the tick in full dynticks
  sched: Kick full dynticks CPU that have more than one task enqueued.
  perf: New helper to prevent full dynticks CPUs from stopping tick
  perf: Kick full dynticks CPU if events rotation is needed
  ...
2013-05-05 13:23:27 -07:00
Frederic Weisbecker 73c3082877 rcu: Fix full dynticks' dependency on wide RCU nocb mode
Commit 0637e02939
("nohz: Select wide RCU nocb for full dynticks") intended
to force CONFIG_RCU_NOCB_CPU_ALL=y when full dynticks is
enabled.

However this option is part of a choice menu and Kconfig's
"select" instruction has no effect on such targets.

Fix this by using reverse dependencies on the targets we
don't want instead.

Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-05-04 08:30:34 +02:00
Frederic Weisbecker c032862fba Merge commit '8700c95adb03' into timers/nohz
The full dynticks tree needs the latest RCU and sched
upstream updates in order to fix some dependencies.

Merge a common upstream merge point that has these
updates.

Conflicts:
	include/linux/perf_event.h
	kernel/rcutree.h
	kernel/rcutree_plugin.h

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-05-02 17:54:19 +02:00
Linus Torvalds 20b4fb4852 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...
2013-05-01 17:51:54 -07:00
David Howells 0bb80f2405 proc: Split the namespace stuff out into linux/proc_ns.h
Split the proc namespace stuff out into linux/proc_ns.h.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: netdev@vger.kernel.org
cc: Serge E. Hallyn <serge.hallyn@ubuntu.com>
cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01 17:29:39 -04:00
Steven Rostedt bf5d770bd2 init: Do not warn on non-zero initcall return
Commit f91eb62f71 ("init: scream bloody murder if interrupts are
enabled too early") added three new warnings.  The first two seemed
reasonable, but the third included a warning when an initcall returned
non-zero.  Although, the third WARN() does include an imbalanced preempt
disabled, or irqs disable, it shouldn't warn if it only had an initcall
that just returns non-zero.

In fact, according to Linus, it shouldn't print at all.  As it only
prints with initcall_debug set, and that already shows enough
information to fix things.

Link: http://lkml.kernel.org/r/CA+55aFzaBC5SFi7=F2mfm+KWY5qTsBmOqgbbs8E+LUS8JK-sBg@mail.gmail.com

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-01 10:44:24 -07:00
Mike Frysinger 657a52095f init/Kconfig: re-order CONFIG_EXPERT options to fix menuconfig display
The kconfig language requires that dependent options all follow the
menuconfig symbol in order to be collapsed below it.  Recently some hidden
options were added below the EXPERT menuconfig, but did not depend on
EXPERT (because hidden options can't).  This broke the display.  So
re-order all these options, and while we're here stick the PCI quirks
under the EXPERT menu (since it isn't sitting with any related options).

Before this commit, we get:
	[*] Configure standard kernel features (expert users)  --->
	[ ] Sysctl syscall support
	[*] Load all symbols for debugging/ksymoops
	...
	[ ] Embedded system

Now we get the older (and correct) behavior:
	[*] Configure standard kernel features (expert users)  --->
	[ ] Embedded system
And if you go into the expert menu you get the expert options:
	[ ] Sysctl syscall support
	[*] Load all symbols for debugging/ksymoops
	...

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:09 -07:00
Lucas De Marchi 907ed1328d usermodehelper: split remaining calls to call_usermodehelper_fns()
These are the only users of call_usermodehelper_fns().  This function
suffers from not being able to determine if the cleanup is called.  Even
if in this places the cleanup pointer is NULL, convert them to use the
separate call_usermodehelper_setup() + call_usermodehelper_exec()
functions so we can remove the _fns variant.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:06 -07:00
Linus Torvalds ab86e974f0 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core timer updates from Ingo Molnar:
 "The main changes in this cycle's merge are:

   - Implement shadow timekeeper to shorten in kernel reader side
     blocking, by Thomas Gleixner.

   - Posix timers enhancements by Pavel Emelyanov:

   - allocate timer ID per process, so that exact timer ID allocations
     can be re-created be checkpoint/restore code.

   - debuggability and tooling (/proc/PID/timers, etc.) improvements.

   - suspend/resume enhancements by Feng Tang: on certain new Intel Atom
     processors (Penwell and Cloverview), there is a feature that the
     TSC won't stop in S3 state, so the TSC value won't be reset to 0
     after resume.  This can be taken advantage of by the generic via
     the CLOCK_SOURCE_SUSPEND_NONSTOP flag: instead of using the RTC to
     recover/approximate sleep time, the main (and precise) clocksource
     can be used.

   - Fix /proc/timer_list for 4096 CPUs by Nathan Zimmer: on so many
     CPUs the file goes beyond 4MB of size and thus the current
     simplistic seqfile approach fails.  Convert /proc/timer_list to a
     proper seq_file with its own iterator.

   - Cleanups and refactorings of the core timekeeping code by John
     Stultz.

   - International Atomic Clock time is managed by the NTP code
     internally currently but not exposed externally.  Separate the TAI
     code out and add CLOCK_TAI support and TAI support to the hrtimer
     and posix-timer code, by John Stultz.

   - Add deep idle support enhacement to the broadcast clockevents core
     timer code, by Daniel Lezcano: add an opt-in CLOCK_EVT_FEAT_DYNIRQ
     clockevents feature (which will be utilized by future clockevents
     driver updates), which allows the use of IRQ affinities to avoid
     spurious wakeups of idle CPUs - the right CPU with an expiring
     timer will be woken.

   - Add new ARM bcm281xx clocksource driver, by Christian Daudt

   - ... various other fixes and cleanups"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  clockevents: Set dummy handler on CPU_DEAD shutdown
  timekeeping: Update tk->cycle_last in resume
  posix-timers: Remove unused variable
  clockevents: Switch into oneshot mode even if broadcast registered late
  timer_list: Convert timer list to be a proper seq_file
  timer_list: Split timer_list_show_tickdevices
  posix-timers: Show sigevent info in proc file
  posix-timers: Introduce /proc/PID/timers file
  posix timers: Allocate timer id per process (v2)
  timekeeping: Make sure to notify hrtimers when TAI offset changes
  hrtimer: Fix ktime_add_ns() overflow on 32bit architectures
  hrtimer: Add expiry time overflow check in hrtimer_interrupt
  timekeeping: Shorten seq_count region
  timekeeping: Implement a shadow timekeeper
  timekeeping: Delay update of clock->cycle_last
  timekeeping: Store cycle_last value in timekeeper struct as well
  ntp: Remove ntp_lock, using the timekeeping locks to protect ntp state
  timekeeping: Simplify tai updating from do_adjtimex
  timekeeping: Hold timekeepering locks in do_adjtimex and hardpps
  timekeeping: Move ADJ_SETOFFSET to top level do_adjtimex()
  ...
2013-04-30 08:15:40 -07:00
Linus Torvalds 8700c95adb Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP/hotplug changes from Ingo Molnar:
 "This is a pretty large, multi-arch series unifying and generalizing
  the various disjunct pieces of idle routines that architectures have
  historically copied from each other and have grown in random, wildly
  inconsistent and sometimes buggy directions:

   101 files changed, 455 insertions(+), 1328 deletions(-)

  this went through a number of review and test iterations before it was
  committed, it was tested on various architectures, was exposed to
  linux-next for quite some time - nevertheless it might cause problems
  on architectures that don't read the mailing lists and don't regularly
  test linux-next.

  This cat herding excercise was motivated by the -rt kernel, and was
  brought to you by Thomas "the Whip" Gleixner."

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  idle: Remove GENERIC_IDLE_LOOP config switch
  um: Use generic idle loop
  ia64: Make sure interrupts enabled when we "safe_halt()"
  sparc: Use generic idle loop
  idle: Remove unused ARCH_HAS_DEFAULT_IDLE
  bfin: Fix typo in arch_cpu_idle()
  xtensa: Use generic idle loop
  x86: Use generic idle loop
  unicore: Use generic idle loop
  tile: Use generic idle loop
  tile: Enter idle with preemption disabled
  sh: Use generic idle loop
  score: Use generic idle loop
  s390: Use generic idle loop
  powerpc: Use generic idle loop
  parisc: Use generic idle loop
  openrisc: Use generic idle loop
  mn10300: Use generic idle loop
  mips: Use generic idle loop
  microblaze: Use generic idle loop
  ...
2013-04-30 07:50:17 -07:00
Linus Torvalds 16fa94b532 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler changes from Ingo Molnar:
 "The main changes in this development cycle were:

   - full dynticks preparatory work by Frederic Weisbecker

   - factor out the cpu time accounting code better, by Li Zefan

   - multi-CPU load balancer cleanups and improvements by Joonsoo Kim

   - various smaller fixes and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
  sched: Fix init NOHZ_IDLE flag
  sched: Prevent to re-select dst-cpu in load_balance()
  sched: Rename load_balance_tmpmask to load_balance_mask
  sched: Move up affinity check to mitigate useless redoing overhead
  sched: Don't consider other cpus in our group in case of NEWLY_IDLE
  sched: Explicitly cpu_idle_type checking in rebalance_domains()
  sched: Change position of resched_cpu() in load_balance()
  sched: Fix wrong rq's runnable_avg update with rt tasks
  sched: Document task_struct::personality field
  sched/cpuacct/UML: Fix header file dependency bug on the UML build
  cgroup: Kill subsys.active flag
  sched/cpuacct: No need to check subsys active state
  sched/cpuacct: Initialize cpuacct subsystem earlier
  sched/cpuacct: Initialize root cpuacct earlier
  sched/cpuacct: Allocate per_cpu cpuusage for root cpuacct statically
  sched/cpuacct: Clean up cpuacct.h
  sched/cpuacct: Remove redundant NULL checks in cpuacct_acount_field()
  sched/cpuacct: Remove redundant NULL checks in cpuacct_charge()
  sched/cpuacct: Add cpuacct_acount_field()
  sched/cpuacct: Add cpuacct_init()
  ...
2013-04-30 07:43:28 -07:00
Linus Torvalds 1f889ec62c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle are mostly related to preparatory work
  for the full-dynticks work:

   - Remove restrictions on no-CBs CPUs, make RCU_FAST_NO_HZ take
     advantage of numbered callbacks, do callback accelerations based on
     numbered callbacks.  Posted to LKML at
        https://lkml.org/lkml/2013/3/18/960

   - RCU documentation updates.  Posted to LKML at
        https://lkml.org/lkml/2013/3/18/570

   - Miscellaneous fixes.  Posted to LKML at
        https://lkml.org/lkml/2013/3/18/594"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  rcu: Make rcu_accelerate_cbs() note need for future grace periods
  rcu: Abstract rcu_start_future_gp() from rcu_nocb_wait_gp()
  rcu: Rename n_nocb_gp_requests to need_future_gp
  rcu: Push lock release to rcu_start_gp()'s callers
  rcu: Repurpose no-CBs event tracing to future-GP events
  rcu: Rearrange locking in rcu_start_gp()
  rcu: Make RCU_FAST_NO_HZ take advantage of numbered callbacks
  rcu: Accelerate RCU callbacks at grace-period end
  rcu: Export RCU_FAST_NO_HZ parameters to sysfs
  rcu: Distinguish "rcuo" kthreads by RCU flavor
  rcu: Add event tracing for no-CBs CPUs' grace periods
  rcu: Add event tracing for no-CBs CPUs' callback registration
  rcu: Introduce proper blocking to no-CBs kthreads GP waits
  rcu: Provide compile-time control for no-CBs CPUs
  rcu: Tone down debugging during boot-up and shutdown.
  rcu: Add softirq-stall indications to stall-warning messages
  rcu: Documentation update
  rcu: Make bugginess of code sample more evident
  rcu: Fix hlist_bl_set_first_rcu() annotation
  rcu: Delete unused rcu_node "wakemask" field
  ...
2013-04-30 07:39:01 -07:00
Andrew Morton ea676e846a init/main.c: convert to pr_foo()
Also enables cleanup of some 80-col trickery.

Cc: Richard Weinberger <richard@nod.at>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:20 -07:00
Richard Weinberger c2409b004a init: raise log level
If the kernel was booted with the "quiet" boot option we have currently no
chance to see why an initrd fails.  Change KERN_WARNING to KERN_ERR to see
what is going on.

Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:20 -07:00
Steven Rostedt f91eb62f71 init: scream bloody murder if interrupts are enabled too early
As I was testing a lot of my code recently, and having several
"successes", I accidentally noticed in the dmesg this little line:

  start_kernel(): bug: interrupts were enabled *very* early, fixing it

Sure enough, one of my patches two commits ago enabled interrupts early.
The sad part here is that I never noticed it, and I ran several tests with
ktest too, and ktest did not notice this line.

What ktest looks for (and so does many other automated testing scripts) is
a back trace produced by a WARN_ON() or BUG().  As a back trace was never
produced, my buggy patch could have slipped into linux-next, or even
worse, mainline.

Adding a WARN(!irqs_disabled()) makes this bug a little more obvious:

  PID hash table entries: 4096 (order: 3, 32768 bytes)
  __ex_table already sorted, skipping sort
  Checking aperture...
  No AGP bridge found
  Calgary: detecting Calgary via BIOS EBDA area
  Calgary: Unable to locate Rio Grande table in EBDA - bailing!
  Memory: 2003252k/2054848k available (4857k kernel code, 460k absent, 51136k reserved, 6210k data, 1096k init)
  ------------[ cut here ]------------
  WARNING: at /home/rostedt/work/git/linux-trace.git/init/main.c:543 start_kernel+0x21e/0x415()
  Hardware name: To Be Filled By O.E.M.
  Interrupts were enabled *very* early, fixing it
  Modules linked in:
  Pid: 0, comm: swapper/0 Not tainted 3.8.0-test+ #286
  Call Trace:
    warn_slowpath_common+0x83/0x9b
    warn_slowpath_fmt+0x46/0x48
    start_kernel+0x21e/0x415
    x86_64_start_reservations+0x10e/0x112
    x86_64_start_kernel+0x102/0x111
  ---[ end trace 007d8b0491b4f5d8 ]---
  Preemptible hierarchical RCU implementation.
   RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=4.
  NR_IRQS:4352 nr_irqs:712 16
  Console: colour VGA+ 80x25
  console [ttyS0] enabled, bootconsole disabled

Do you see it?

The original version of this patch just slapped a WARN_ON() in there and
kept the printk().  Ard van Breemen suggested using the WARN() interface,
which makes the code a bit cleaner.

Also, while examining other warnings in init/main.c, I found two other
locations that deserve a bloody murder scream if their conditions are hit,
and updated them accordingly.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ard van Breemen <ard@telegraafnet.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:20 -07:00
Frederic Weisbecker c58b0df12a nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config
Turn the full dynticks passive dependency on VIRT_CPU_ACCOUNTING_GEN
to an active one.

The full dynticks Kconfig is currently hidden behind the full dynticks
cputime accounting, which is an awkward and counter-intuitive layout:
the user first has to select the dynticks cputime accounting in order
to make the full dynticks feature to be visible.

We definetly want it the other way around. The usual way to perform
this kind of active dependency is use "select" on the depended target.
Now we can't use the Kconfig "select" instruction when the target is
a "choice".

So this patch inspires on how the RCU subsystem Kconfig interact
with its dependencies on SMP and PREEMPT: we make sure that cputime
accounting can't propose another option than VIRT_CPU_ACCOUNTING_GEN
when NO_HZ_FULL is selected by using the right "depends on" instruction
for each cputime accounting choices.

v2: Keep full dynticks cputime accounting available even without
full dynticks, as per Paul McKenney's suggestion.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-04-26 18:56:59 +02:00
Thomas Gleixner 6402c7dc2a Merge branch 'linus' into timers/core
Reason: Get upstream fixes before adding conflicting code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-24 20:33:54 +02:00
Frederic Weisbecker d1e43fa5f8 nohz: Ensure full dynticks CPUs are RCU nocbs
We need full dynticks CPU to also be RCU nocb so
that we don't have to keep the tick to handle RCU
callbacks.

Make sure the range passed to nohz_full= boot
parameter is a subset of rcu_nocbs=

The CPUs that fail to meet this requirement will be
excluded from the nohz_full range. This is checked
early in boot time, before any CPU has the opportunity
to stop its tick.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-04-19 13:54:04 +02:00
Ingo Molnar 8fcfae3171 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

  * Remove restrictions on no-CBs CPUs, make RCU_FAST_NO_HZ
    take advantage of numbered callbacks, do additional callback
    accelerations based on numbered callbacks.  Posted to LKML
    at https://lkml.org/lkml/2013/3/18/960.

  * RCU documentation updates.  Posted to LKML at
    https://lkml.org/lkml/2013/3/18/570.

  * Miscellaneous fixes.  Posted to LKML at
    https://lkml.org/lkml/2013/3/18/594.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-04-10 12:55:49 +02:00
Thomas Gleixner a1a04ec3c7 idle: Provide a generic entry point for the idle code
For now this calls cpu_idle(), but in the long run we want to move the
cpu bringup code to the core and therefor we add a state argument.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Link: http://lkml.kernel.org/r/20130321215233.583190032@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-08 17:39:23 +02:00
Frederic Weisbecker 3451d0243c nohz: Rename CONFIG_NO_HZ to CONFIG_NO_HZ_COMMON
We are planning to convert the dynticks Kconfig options layout
into a choice menu. The user must be able to easily pick
any of the following implementations: constant periodic tick,
idle dynticks, full dynticks.

As this implies a mutual exclusion, the two dynticks implementions
need to converge on the selection of a common Kconfig option in order
to ease the sharing of a common infrastructure.

It would thus seem pretty natural to reuse CONFIG_NO_HZ to
that end. It already implements all the idle dynticks code
and the full dynticks depends on all that code for now.
So ideally the choice menu would propose CONFIG_NO_HZ_IDLE and
CONFIG_NO_HZ_EXTENDED then both would select CONFIG_NO_HZ.

On the other hand we want to stay backward compatible: if
CONFIG_NO_HZ is set in an older config file, we want to
enable CONFIG_NO_HZ_IDLE by default.

But we can't afford both at the same time or we run into
a circular dependency:

1) CONFIG_NO_HZ_IDLE and CONFIG_NO_HZ_EXTENDED both select
   CONFIG_NO_HZ
2) If CONFIG_NO_HZ is set, we default to CONFIG_NO_HZ_IDLE

We might be able to support that from Kconfig/Kbuild but it
may not be wise to introduce such a confusing behaviour.

So to solve this, create a new CONFIG_NO_HZ_COMMON option
which gathers the common code between idle and full dynticks
(that common code for now is simply the idle dynticks code)
and select it from their referring Kconfig.

Then we'll later create CONFIG_NO_HZ_IDLE and map CONFIG_NO_HZ
to it for backward compatibility.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-04-03 13:56:03 +02:00
Paul E. McKenney c0f4dfd4f9 rcu: Make RCU_FAST_NO_HZ take advantage of numbered callbacks
Because RCU callbacks are now associated with the number of the grace
period that they must wait for, CPUs can now take advance callbacks
corresponding to grace periods that ended while a given CPU was in
dyntick-idle mode.  This eliminates the need to try forcing the RCU
state machine while entering idle, thus reducing the CPU intensiveness
of RCU_FAST_NO_HZ, which should increase its energy efficiency.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-03-26 08:04:51 -07:00
Paul E. McKenney a488985851 rcu: Distinguish "rcuo" kthreads by RCU flavor
Currently, the per-no-CBs-CPU kthreads are named "rcuo" followed by
the CPU number, for example, "rcuo".  This is problematic given that
there are either two or three RCU flavors, each of which gets a per-CPU
kthread with exactly the same name.  This commit therefore introduces
a one-letter abbreviation for each RCU flavor, namely 'b' for RCU-bh,
'p' for RCU-preempt, and 's' for RCU-sched.  This abbreviation is used
to distinguish the "rcuo" kthreads, for example, for CPU 0 we would have
"rcuob/0", "rcuop/0", and "rcuos/0".

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
2013-03-26 08:04:48 -07:00
Paul E. McKenney 911af505ef rcu: Provide compile-time control for no-CBs CPUs
Currently, the only way to specify no-CBs CPUs is via the rcu_nocbs
kernel command-line parameter.  This is inconvenient in some cases,
particularly for randconfig testing, so this commit adds a new set of
kernel configuration parameters.  CONFIG_RCU_NOCB_CPU_NONE (the default)
retains the old behavior, CONFIG_RCU_NOCB_CPU_ZERO offloads callback
processing from CPU 0 (along with any other CPUs specified by the
rcu_nocbs boot-time parameter), and CONFIG_RCU_NOCB_CPU_ALL offloads
callback processing from all CPUs.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-03-26 08:04:43 -07:00
Kees Cook 3d374d09f1 final removal of CONFIG_EXPERIMENTAL
Remove "config EXPERIMENTAL" itself, now that every "depends on" it has
been removed from the tree.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-12 16:30:27 -07:00
Paul E. McKenney 34ed62461a rcu: Remove restrictions on no-CBs CPUs
Currently, CPU 0 is constrained to not be a no-CBs CPU, and furthermore
at least one no-CBs CPU must remain online at any given time.  These
restrictions are problematic in some situations, such as cases where
all CPUs must run a real-time workload that needs to be insulated from
OS jitter and latencies due to RCU callback invocation.  This commit
therefore provides no-CBs CPUs a (very crude and energy-inefficient)
way to start and to wait for grace periods independently of the normal
RCU callback mechanisms.  This approach allows any or all of the CPUs to
be designated as no-CBs CPUs, and allows any proper subset of the CPUs
(whether no-CBs CPUs or not) to be offlined.

This commit also provides a fix for a locking bug spotted by Xie
ChanglongX <changlongx.xie@intel.com>.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-03-12 11:17:51 -07:00
Frederic Weisbecker 8b43876643 context_tracking: Enable probes by default for selftesting
Until we provide the nohz_mask boot parameter, keeping
the context tracking probes disabled by default is pointless
since what we want is to runtime test this code anyway.

It's furthermore confusing for the users which don't expect
the probes to be off when they select RCU user mode or full
dynticks cputime accounting.

Let's enable these probes selftests by default for now.

Suggested: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Mats Liljegren <mats.liljegren@enea.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-03-07 17:10:41 +01:00
Thomas Gleixner ad2b13536a tick: Call tick_init late
To convert the clockevents code to cpumask_var_t we need to move the
init call after the allocator setup. 

Clockevents are earliest registered from time_init() as they need
interrupts being set up, so this is safe.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130306111537.304379448@linutronix.de
Cc: Rusty Russell <rusty@rustcorp.com.au>
2013-03-07 16:13:25 +01:00
Linus Torvalds e23b62256a Initial ARC Linux port with some fixes on top for 3.9-rc1
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Merge tag 'arc-v3.9-rc1-late' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull new ARC architecture from Vineet Gupta:
 "Initial ARC Linux port with some fixes on top for 3.9-rc1:

  I would like to introduce the Linux port to ARC Processors (from
  Synopsys) for 3.9-rc1.  The patch-set has been discussed on the public
  lists since Nov and has received a fair bit of review, specially from
  Arnd, tglx, Al and other subsystem maintainers for DeviceTree, kgdb...

  The arch bits are in arch/arc, some asm-generic changes (acked by
  Arnd), a minor change to PARISC (acked by Helge).

  The series is a touch bigger for a new port for 2 main reasons:

   1. It enables a basic kernel in first sub-series and adds
      ptrace/kgdb/.. later

   2. Some of the fallout of review (DeviceTree support, multi-platform-
      image support) were added on top of orig series, primarily to
      record the revision history.

  This updated pull request additionally contains

   - fixes due to our GNU tools catching up with the new syscall/ptrace
     ABI

   - some (minor) cross-arch Kconfig updates."

* tag 'arc-v3.9-rc1-late' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (82 commits)
  ARC: split elf.h into uapi and export it for userspace
  ARC: Fixup the current ABI version
  ARC: gdbserver using regset interface possibly broken
  ARC: Kconfig cleanup tracking cross-arch Kconfig pruning in merge window
  ARC: make a copy of flat DT
  ARC: [plat-arcfpga] DT arc-uart bindings change: "baud" => "current-speed"
  ARC: Ensure CONFIG_VIRT_TO_BUS is not enabled
  ARC: Fix pt_orig_r8 access
  ARC: [3.9] Fallout of hlist iterator update
  ARC: 64bit RTSC timestamp hardware issue
  ARC: Don't fiddle with non-existent caches
  ARC: Add self to MAINTAINERS
  ARC: Provide a default serial.h for uart drivers needing BASE_BAUD
  ARC: [plat-arcfpga] defconfig for fully loaded ARC Linux
  ARC: [Review] Multi-platform image #8: platform registers SMP callbacks
  ARC: [Review] Multi-platform image #7: SMP common code to use callbacks
  ARC: [Review] Multi-platform image #6: cpu-to-dma-addr optional
  ARC: [Review] Multi-platform image #5: NR_IRQS defined by ARC core
  ARC: [Review] Multi-platform image #4: Isolate platform headers
  ARC: [Review] Multi-platform image #3: switch to board callback
  ...
2013-03-02 07:58:56 -08:00
Linus Torvalds 94f2f14234 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace and namespace infrastructure changes from Eric W Biederman:
 "This set of changes starts with a few small enhnacements to the user
  namespace.  reboot support, allowing more arbitrary mappings, and
  support for mounting devpts, ramfs, tmpfs, and mqueuefs as just the
  user namespace root.

  I do my best to document that if you care about limiting your
  unprivileged users that when you have the user namespace support
  enabled you will need to enable memory control groups.

  There is a minor bug fix to prevent overflowing the stack if someone
  creates way too many user namespaces.

  The bulk of the changes are a continuation of the kuid/kgid push down
  work through the filesystems.  These changes make using uids and gids
  typesafe which ensures that these filesystems are safe to use when
  multiple user namespaces are in use.  The filesystems converted for
  3.9 are ceph, 9p, afs, ocfs2, gfs2, ncpfs, nfs, nfsd, and cifs.  The
  changes for these filesystems were a little more involved so I split
  the changes into smaller hopefully obviously correct changes.

  XFS is the only filesystem that remains.  I was hoping I could get
  that in this release so that user namespace support would be enabled
  with an allyesconfig or an allmodconfig but it looks like the xfs
  changes need another couple of days before it they are ready."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (93 commits)
  cifs: Enable building with user namespaces enabled.
  cifs: Convert struct cifs_ses to use a kuid_t and a kgid_t
  cifs: Convert struct cifs_sb_info to use kuids and kgids
  cifs: Modify struct smb_vol to use kuids and kgids
  cifs: Convert struct cifsFileInfo to use a kuid
  cifs: Convert struct cifs_fattr to use kuid and kgids
  cifs: Convert struct tcon_link to use a kuid.
  cifs: Modify struct cifs_unix_set_info_args to hold a kuid_t and a kgid_t
  cifs: Convert from a kuid before printing current_fsuid
  cifs: Use kuids and kgids SID to uid/gid mapping
  cifs: Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID to keyring_alloc
  cifs: Use BUILD_BUG_ON to validate uids and gids are the same size
  cifs: Override unmappable incoming uids and gids
  nfsd: Enable building with user namespaces enabled.
  nfsd: Properly compare and initialize kuids and kgids
  nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids
  nfsd: Modify nfsd4_cb_sec to use kuids and kgids
  nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion
  nfsd: Convert nfsxdr to use kuids and kgids
  nfsd: Convert nfs3xdr to use kuids and kgids
  ...
2013-02-25 16:00:49 -08:00
Linus Torvalds 9043a2650c The sweeping change is to make add_taint() explicitly indicate whether to disable
lockdep, but it's a mechanical change.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module update from Rusty Russell:
 "The sweeping change is to make add_taint() explicitly indicate whether
  to disable lockdep, but it's a mechanical change."

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  MODSIGN: Add option to not sign modules during modules_install
  MODSIGN: Add -s <signature> option to sign-file
  MODSIGN: Specify the hash algorithm on sign-file command line
  MODSIGN: Simplify Makefile with a Kconfig helper
  module: clean up load_module a little more.
  modpost: Ignore ARC specific non-alloc sections
  module: constify within_module_*
  taint: add explicit flag to show whether lock dep is still OK.
  module: printk message when module signature fail taints kernel.
2013-02-25 15:41:43 -08:00
Linus Torvalds 27ea6dfdc2 Misc ia64 bits for 3.9
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Merge tag 'please-pull-misc-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux

Pull misc ia64 bits from Tony Luck.

* tag 'please-pull-misc-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  MAINTAINERS: update SGI & ia64 Altix stuff
  sysctl: Enable IA64 "ignore-unaligned-usertrap" to be used cross-arch
2013-02-21 17:55:48 -08:00
Linus Torvalds 06991c28f3 Driver core patches for 3.9-rc1
Here is the big driver core merge for 3.9-rc1
 
 There are two major series here, both of which touch lots of drivers all
 over the kernel, and will cause you some merge conflicts:
   - add a new function called devm_ioremap_resource() to properly be
     able to check return values.
   - remove CONFIG_EXPERIMENTAL
 
 If you need me to provide a merged tree to handle these resolutions,
 please let me know.
 
 Other than those patches, there's not much here, some minor fixes and
 updates.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core patches from Greg Kroah-Hartman:
 "Here is the big driver core merge for 3.9-rc1

  There are two major series here, both of which touch lots of drivers
  all over the kernel, and will cause you some merge conflicts:

   - add a new function called devm_ioremap_resource() to properly be
     able to check return values.

   - remove CONFIG_EXPERIMENTAL

  Other than those patches, there's not much here, some minor fixes and
  updates"

Fix up trivial conflicts

* tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits)
  base: memory: fix soft/hard_offline_page permissions
  drivercore: Fix ordering between deferred_probe and exiting initcalls
  backlight: fix class_find_device() arguments
  TTY: mark tty_get_device call with the proper const values
  driver-core: constify data for class_find_device()
  firmware: Ignore abort check when no user-helper is used
  firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER
  firmware: Make user-mode helper optional
  firmware: Refactoring for splitting user-mode helper code
  Driver core: treat unregistered bus_types as having no devices
  watchdog: Convert to devm_ioremap_resource()
  thermal: Convert to devm_ioremap_resource()
  spi: Convert to devm_ioremap_resource()
  power: Convert to devm_ioremap_resource()
  mtd: Convert to devm_ioremap_resource()
  mmc: Convert to devm_ioremap_resource()
  mfd: Convert to devm_ioremap_resource()
  media: Convert to devm_ioremap_resource()
  iommu: Convert to devm_ioremap_resource()
  drm: Convert to devm_ioremap_resource()
  ...
2013-02-21 12:05:51 -08:00
Linus Torvalds ece8e0b2f9 Merge branch 'for-3.9-async' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull async changes from Tejun Heo:
 "These are followups for the earlier deadlock issue involving async
  ending up waiting for itself through block requesting module[1].  The
  following changes are made by these commits.

   - Instead of requesting default elevator on each request_queue init,
     block now requests it once early during boot.

   - Kmod triggers warning if invoked from an async worker.

   - Async synchronization implementation has been reimplemented.  It's
     a lot simpler now."

* 'for-3.9-async' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  async: initialise list heads to fix crash
  async: replace list of active domains with global list of pending items
  async: keep pending tasks on async_domain and remove async_pending
  async: use ULLONG_MAX for infinity cookie value
  async: bring sanity to the use of words domain and running
  async, kmod: warn on synchronous request_module() from async workers
  block: don't request module during elevator init
  init, block: try to load default elevator module early during boot
2013-02-19 22:10:26 -08:00
Linus Torvalds d652e1eb8e Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler changes from Ingo Molnar:
 "Main changes:

   - scheduler side full-dynticks (user-space execution is undisturbed
     and receives no timer IRQs) preparation changes that convert the
     cputime accounting code to be full-dynticks ready, from Frederic
     Weisbecker.

   - Initial sched.h split-up changes, by Clark Williams

   - select_idle_sibling() performance improvement by Mike Galbraith:

        " 1 tbench pair (worst case) in a 10 core + SMT package:

          pre   15.22 MB/sec 1 procs
          post 252.01 MB/sec 1 procs "

  - sched_rr_get_interval() ABI fix/change.  We think this detail is not
    used by apps (so it's not an ABI in practice), but lets keep it
    under observation.

  - misc RT scheduling cleanups, optimizations"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  sched/rt: Add <linux/sched/rt.h> header to <linux/init_task.h>
  cputime: Remove irqsave from seqlock readers
  sched, powerpc: Fix sched.h split-up build failure
  cputime: Restore CPU_ACCOUNTING config defaults for PPC64
  sched/rt: Move rt specific bits into new header file
  sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice
  sched: Move sched.h sysctl bits into separate header
  sched: Fix signedness bug in yield_to()
  sched: Fix select_idle_sibling() bouncing cow syndrome
  sched/rt: Further simplify pick_rt_task()
  sched/rt: Do not account zero delta_exec in update_curr_rt()
  cputime: Safely read cputime of full dynticks CPUs
  kvm: Prepare to add generic guest entry/exit callbacks
  cputime: Use accessors to read task cputime stats
  cputime: Allow dynamic switch between tick/virtual based cputime accounting
  cputime: Generic on-demand virtual cputime accounting
  cputime: Move default nsecs_to_cputime() to jiffies based cputime file
  cputime: Librarize per nsecs resolution cputime definitions
  cputime: Avoid multiplication overflow on utime scaling
  context_tracking: Export context state for generic vtime
  ...

Fix up conflict in kernel/context_tracking.c due to comment additions.
2013-02-19 18:19:48 -08:00
Linus Torvalds b7133a9a10 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq core changes from Ingo Molnar:
 "The biggest changes are the IRQ-work and printk changes from Frederic
  Weisbecker, which prepare the code for 'full dynticks' (the ability to
  stop or slow down the periodic tick arbitrarily, not just in idle time
  as today):

   - Don't stop tick with irq works pending.  This fix is generally
     useful and concerns archs that can't raise self IPIs.

   - Flush irq works before CPU offlining.

   - Introduce "lazy" irq works that can wait for the next tick to be
     executed, unless it's stopped.

   - Implement klogd wake up using irq work.  This removes the ad-hoc
     printk_tick()/printk_needs_cpu() hooks and make it working even in
     dynticks mode.

   - Cleanups and fixes."

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Export enable/disable_percpu_irq()
  arch Kconfig: Remove references to IRQ_PER_CPU
  irq_work: Remove return value from the irq_work_queue() function
  genirq: Avoid deadlock in spurious handling
  printk: Wake up klogd using irq_work
  irq_work: Make self-IPIs optable
  irq_work: Warn if there's still work on cpu_down
  irq_work: Flush work on CPU_DYING
  irq_work: Don't stop the tick with pending works
  nohz: Add API to check tick state
  irq_work: Remove CONFIG_HAVE_IRQ_WORK
  irq_work: Fix racy check on work pending flag
  irq_work: Fix racy IRQ_WORK_BUSY flag setting
2013-02-19 17:47:58 -08:00
Vineet Gupta bf14e3b979 sysctl: Enable PARISC "unaligned-trap" to be used cross-arch
PARISC defines /proc/sys/kernel/unaligned-trap to runtime toggle
unaligned access emulation.

The exact mechanics of enablig/disabling are still arch specific, we can
make the sysctl usable by other arches.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
2013-02-15 23:16:05 +05:30
Eric W. Biederman 139321c65c cifs: Enable building with user namespaces enabled.
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 07:28:56 -08:00
Eric W. Biederman c9617a44b3 nfsd: Enable building with user namespaces enabled.
Now that the kuids and kgids conversion have propogated
through net/sunrpc/ and the fs/nfsd/ it is safe to enable
building nfsd when user namespaces are enabled.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:16:10 -08:00
Eric W. Biederman 4277bbf750 nfs: Enable building with user namespaces enabled.
Now that the kuids and kgids conversion have propogated
through net/sunrpc/ and the fs/nfs/ it is safe to enable
building nfs when user namespaces are enabled.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:34 -08:00
Eric W. Biederman 1ac7fd8190 ncpfs: Support interacting with multiple user namespaces
ncpfs does not natively support uids and gids so this conversion was
simply a matter of updating the the type of the mounteduid, the uid
and the gid on the superblock. Fixing the ioctls that read them,
updating the mount option parser and the mount option printer.

Cc: Petr Vandrovec <petr@vandrovec.name>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2013-02-13 06:15:13 -08:00
Eric W. Biederman 0f07bd3753 gfs2: Enable building with user namespaces enabled
Now that all of the necessary work has been done to push kuids and
kgids throughout gfs2 and to convert between kuids and kgids when
reading and writing the on disk structures it is safe to enable gfs2
when multiple user namespaces are enabled.

Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:12 -08:00
Eric W. Biederman ecb528e3ea ocfs2: Enable building with user namespaces enabled
Now that ocfs2 has been converted to store uids and gids in
kuid_t and kgid_t and all of the conversions have been added
to the appropriate places it is safe to allow building and
using ocfs2 with user namespace support enabled.

Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:14:32 -08:00
Eric W. Biederman 515ee7bd97 coda: Allow coda to be built when user namespace support is enabled
Now that the coda kernel to userspace has been modified to convert
between kuids and kgids and uids and gids, and all internal
coda structures have be modified to store uids and gids as
kuids and kgids it is safe to allow code to be built with
user namespace support enabled.

Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:00:55 -08:00
Eric W. Biederman a0a5386ac6 afs: Support interacting with multiple user namespaces
Modify struct afs_file_status to store owner as a kuid_t and group as
a kgid_t.

In xdr_decode_AFSFetchStatus as owner is now a kuid_t and group is now
a kgid_t don't use the EXTRACT macro.  Instead perform the work of
the extract macro explicitly.  Read the value with ntohl and
convert it to the appropriate type with make_kuid or make_kgid.
Test if the value is different from what is stored in status and
update changed.   Update the value in status.

In xdr_encode_AFS_StoreStatus call from_kuid or from_kgid as
we are computing the on the wire encoding.

Initialize uids with GLOBAL_ROOT_UID instead of 0.
Initialize gids with GLOBAL_ROOT_GID instead of 0.

Cc: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2013-02-13 06:00:51 -08:00
Eric W. Biederman 4fa814be25 9p: Allow building 9p with user namespaces enabled.
Now that the uid_t -> kuid_t, gid_t -> kgid_t conversion
has been completed in 9p allow 9p to be built when user
namespaces are enabled.

Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-12 03:19:35 -08:00
Eric W. Biederman d5ea055f1c ceph: Enable building when user namespaces are enabled.
Now that conversions happen from kuids and kgids when generating ceph
messages and conversion happen to kuids and kgids after receiving
celph messages, and all intermediate data structures store uids and
gids as type kuid_t and kgid_t it is safe to enable ceph with
user namespace support enabled.

Cc: Sage Weil <sage@inktank.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-12 03:19:28 -08:00
Stephen Rothwell 02fc8d3722 cputime: Restore CPU_ACCOUNTING config defaults for PPC64
Commit abf917cd91 ("cputime: Generic on-demand virtual cputime
accounting") inadvertantly changed the default CPU_ACCOUNTING
config for PPC64.  Repair that.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: ppc-dev <linuxppc-dev@lists.ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Link: http://lkml.kernel.org/r/20130208141938.f31b7b9e1acac5bbe769ee4c@canb.auug.org.au
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-08 15:23:12 +01:00
Clark Williams 8bd75c77b7 sched/rt: Move rt specific bits into new header file
Move rt scheduler definitions out of include/linux/sched.h into
new file include/linux/sched/rt.h

Signed-off-by: Clark Williams <williams@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20130207094707.7b9f825f@riff.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-07 20:51:08 +01:00
Clark Williams cf4aebc292 sched: Move sched.h sysctl bits into separate header
Move the sysctl-related bits from include/linux/sched.h into
a new file: include/linux/sched/sysctl.h. Then update source
files requiring access to those bits by including the new
header file.

Signed-off-by: Clark Williams <williams@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20130207094659.06dced96@riff.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-07 20:50:54 +01:00