Commit Graph

19122 Commits

Author SHA1 Message Date
Andy Lutomirski
ff7e0055bb module: Clean up ro/nx after early module load failures
The commit

    4982223e51 module: set nx before marking module MODULE_STATE_COMING.

introduced a regression: if a module fails to parse its arguments or
if mod_sysfs_setup fails, then the module's memory will be freed
while still read-only.  Anything that reuses that memory will crash
as soon as it tries to write to it.

Cc: stable@vger.kernel.org # v3.16
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-16 04:47:00 +09:30
Linus Torvalds
c9d26423e5 Merge tag 'pm+acpi-3.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI and power management updates from Rafael Wysocki:
 "These are a couple of regression fixes, cpuidle menu governor
  optimizations, fixes for ACPI proccessor and battery drivers,
  hibernation fix to avoid problems related to the e820 memory map,
  fixes for a few cpufreq drivers and a new version of the suspend
  profiling tool analyze_suspend.py.

  Specifics:

   - Fix for an ACPI-based device hotplug regression introduced in 3.14
     that causes a kernel panic to trigger when memory hot-remove is
     attempted with CONFIG_ACPI_HOTPLUG_MEMORY unset from Tang Chen

   - Fix for a cpufreq regression introduced in 3.16 that triggers a
     "sleeping function called from invalid context" bug in
     dev_pm_opp_init_cpufreq_table() from Stephen Boyd

   - ACPI battery driver fix for a warning message added in 3.16 that
     prints silly stuff sometimes from Mariusz Ceier

   - Hibernation fix for safer handling of mismatches in the 820 memory
     map between the configurations during image creation and during the
     subsequent restore from Chun-Yi Lee

   - ACPI processor driver fix to handle CPU hotplug notifications
     correctly during system suspend/resume from Lan Tianyu

   - Series of four cpuidle menu governor cleanups that also should
     speed it up a bit from Mel Gorman

   - Fixes for the speedstep-smi, integrator, cpu0 and arm_big_little
     cpufreq drivers from Hans Wennborg, Himangi Saraogi, Markus
     Pargmann and Uwe Kleine-König

   - Version 3.0 of the analyze_suspend.py suspend profiling tool from
     Todd E Brandt"

* tag 'pm+acpi-3.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / battery: Fix warning message in acpi_battery_get_state()
  PM / tools: analyze_suspend.py: update to v3.0
  cpufreq: arm_big_little: fix module license spec
  cpufreq: speedstep-smi: fix decimal printf specifiers
  ACPI / hotplug: Check scan handlers in acpi_scan_hot_remove()
  cpufreq: OPP: Avoid sleeping while atomic
  cpufreq: cpu0: Do not print error message when deferring
  cpufreq: integrator: Use set_cpus_allowed_ptr
  PM / hibernate: avoid unsafe pages in e820 reserved regions
  ACPI / processor: Make acpi_cpu_soft_notify() process CPU FROZEN events
  cpuidle: menu: Lookup CPU runqueues less
  cpuidle: menu: Call nr_iowait_cpu less times
  cpuidle: menu: Use ktime_to_us instead of reinventing the wheel
  cpuidle: menu: Use shifts when calculating averages where possible
2014-08-14 18:13:46 -06:00
John Stultz
0680eb1f48 timekeeping: Another fix to the VSYSCALL_OLD update_vsyscall
Benjamin Herrenschmidt pointed out that I further missed modifying
update_vsyscall after the wall_to_mono value was changed to a
timespec64.  This causes issues on powerpc32, which expects a 32bit
timespec.

This patch fixes the problem by properly converting from a timespec64 to
a timespec before passing the value on to the arch-specific vsyscall
logic.

[ Thomas is currently on vacation, but reviewed it and wanted me to send
  this fix on to you directly. ]

Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-14 11:04:11 -06:00
Linus Torvalds
1d508f8ace Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull more powerpc updates from Ben Herrenschmidt:
 "Here are some more powerpc bits for 3.17, essentially fixes.

  The biggest series, also aimed at -stable, is from Aneesh and is the
  result of weeks and weeks of debugging to find out why the heck or THP
  implementation was occasionally triggering multi-hit errors in our
  level 1 TLB.  It ended up being a combination of issues including
  subtleties as to how we should invalidate those special 'MPSS' pages
  we use to allow the use of 16M pages inside 4K/64K "base page size"
  segments (you really have to love our MMU !)

  Another interesting one in the "OMG" category is the series from
  Michael adding memory barriers to spin_is_locked().  That's also the
  result of many days of debugging to figure out why the semaphore code
  would occasionally crash in ways that made no sense.  It ended up
  being some creative lock stacking that was defeated by the fact that
  our locks allow a load inside the locked section to be re-ordered with
  the load of the lock value itself (I'm still of two mind about whether
  to kill that once and for all by putting a heavier barrier back into
  our lock implementation...).  The fixes come with a long explanation
  in the cset comments, feel free to read it if you feel like having a
  headache today"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
  powerpc/thp: Add tracepoints to track hugepage invalidate
  powerpc/mm: Use read barrier when creating real_pte
  powerpc/thp: Use ACCESS_ONCE when loading pmdp
  powerpc/thp: Invalidate with vpn in loop
  powerpc/thp: Handle combo pages in invalidate
  powerpc/thp: Invalidate old 64K based hash page mapping before insert of 4k pte
  powerpc/thp: Don't recompute vsid and ssize in loop on invalidate
  powerpc/thp: Add write barrier after updating the valid bit
  powerpc: reorder per-cpu NUMA information's initialization
  powerpc/perf/hv-24x7: Use kmem_cache_free
  powerpc/pseries/hvcserver: Fix endian issue in hvcs_get_partner_info
  powerpc: Hard disable interrupts in xmon
  powerpc: remove duplicate definition of TEXASR_FS
  powerpc/pseries: Avoid deadlock on removing ddw
  powerpc/pseries: Failure on removing device node
  powerpc/boot: Use correct zlib types for comparison
  powerpc/powernv: Interface to register/unregister opal dump region
  printk: Add function to return log buffer address and size
  powerpc: Add POWER8 features to CPU_FTRS_POSSIBLE/ALWAYS
  powerpc/ppc476: Disable BTAC
  ...
2014-08-14 10:14:07 -06:00
Linus Torvalds
311bf6d1cb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull seccomp fix from James Morris.

BUG(!spin_is_locked()) really doesn't work very well in UP
configurations without any actual spinlock state.  Which is very much
why we have that "assert_spin_lock()" function for this.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock
2014-08-14 10:09:48 -06:00
Waiman Long
f0bab73cb5 locking/lockdep: Restrict the use of recursive read_lock() with qrwlock
Unlike the original unfair rwlock implementation, queued rwlock
will grant lock according to the chronological sequence of the lock
requests except when the lock requester is in the interrupt context.
Consequently, recursive read_lock calls will now hang the process if
there is a write_lock call somewhere in between the read_lock calls.

This patch updates the lockdep implementation to look for recursive
read_lock calls. A new read state (3) is used to mark those read_lock
call that cannot be recursively called except in the interrupt
context. The new read state does exhaust the 2 bits available in
held_lock:read bit field. The addition of any new read state in the
future may require a redesign of how all those bits are squeezed
together in the held_lock structure.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1407345722-61615-2-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:33:34 +02:00
Davidlohr Bueso
214e0aed63 locking/Documentation: Move locking related docs into Documentation/locking/
Specifically:
  Documentation/locking/lockdep-design.txt
  Documentation/locking/lockstat.txt
  Documentation/locking/mutex-design.txt
  Documentation/locking/rt-mutex-design.txt
  Documentation/locking/rt-mutex.txt
  Documentation/locking/spinlocks.txt
  Documentation/locking/ww-mutex-design.txt

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hp.com
Cc: aswin@hp.com
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Mason <clm@fb.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Josef Bacik <jbacik@fusionio.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lubomir Rintel <lkundrak@v3.sk>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: fengguang.wu@intel.com
Link: http://lkml.kernel.org/r/1406752916-3341-6-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:32:03 +02:00
Davidlohr Bueso
7608a43d8f locking/mutexes: Use MUTEX_SPIN_ON_OWNER when appropriate
4badad35 ("locking/mutex: Disable optimistic spinning on some
architectures") added a ARCH_SUPPORTS_ATOMIC_RMW flag to
disable the mutex optimistic feature on specific archs.

Because CONFIG_MUTEX_SPIN_ON_OWNER only depended on DEBUG and
SMP, it was ok to have the ->owner field conditional a bit
flexible. However by adding a new variable to the matter,
we can waste space with the unused field, ie: CONFIG_SMP &&
(!CONFIG_MUTEX_SPIN_ON_OWNER && !CONFIG_DEBUG_MUTEX).

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Jason Low <jason.low2@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: aswin@hp.com
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: http://lkml.kernel.org/r/1406752916-3341-5-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:32:02 +02:00
Davidlohr Bueso
76916515d9 locking/mutexes: Refactor optimistic spinning code
When we fail to acquire the mutex in the fastpath, we end up calling
__mutex_lock_common(). A *lot* goes on in this function. Move out the
optimistic spinning code into mutex_optimistic_spin() and simplify
the former a bit. Furthermore, this is similar to what we have in
rwsems. No logical changes.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Jason Low <jason.low2@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: aswin@hp.com
Cc: mingo@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406752916-3341-4-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:32:01 +02:00
Davidlohr Bueso
aa9fc0c19b locking/mcs: Remove obsolete comment
... as we clearly inline mcs_spin_lock() now.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Jason Low <jason.low2@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: aswin@hp.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406752916-3341-3-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:32:00 +02:00
Davidlohr Bueso
42fa566bd7 locking/mutexes: Document quick lock release when unlocking
When unlocking, we always want to reach the slowpath with the lock's counter
indicating it is unlocked. -- as returned by the asm fastpath call or by
explicitly setting it. While doing so, at least in theory, we can optimize
and allow faster lock stealing.

When unlocking, we always want to reach the slowpath with the lock's counter
indicating it is unlocked. -- as returned by the asm fastpath call or by
explicitly setting it. While doing so, at least in theory, we can optimize
and allow faster lock stealing.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hp.com
Cc: aswin@hp.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406752916-3341-2-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:31:59 +02:00
Davidlohr Bueso
242489cfe9 locking/mutexes: Standardize arguments in lock/unlock slowpaths
Just how the locking-end behaves, when unlocking, go ahead and
obtain the proper data structure immediately after the previous
(asm-end) call exits and there are (probably) pending waiters.
This simplifies a bit some of the layering.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hp.com
Cc: aswin@hp.com
Cc: mingo@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1406752916-3341-1-git-send-email-davidlohr@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:31:58 +02:00
Peter Zijlstra
2e39465abc locking: Remove deprecated smp_mb__() barriers
Its been a while and there are no in-tree users left, so remove the
deprecated barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chen, Gong <gong.chen@linux.intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Cc: John Sullivan <jsrhbz@kanargh.force9.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:31:57 +02:00
Sebastian Andrzej Siewior
e708d7ad80 perf: Do poll_wait() before checking condition in perf_poll()
One should first enqueue to the waitqueue and then check for the
condition. If the condition gets true after mutex_unlock() but before
poll_wait() then we lose it and would have wait for another wakeup.

This has been like this since v2.6.31-rc1 commit c7138f37f9 ("perf_counter:
fix perf_poll()"). Before that it was slightly worse. I guess we get enough
wakeups so if we miss here one it doesn't really matter. It is still a
bad example.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1407159068-1478-1-git-send-email-bigeasy@linutronix.de
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 07:51:11 +02:00
Jiri Olsa
fadfe7be6e perf: Add queued work to remove orphaned child events
In cases when the  owner task exits before the workload and the
workload made some forks, all the events stay in until the last
workload process exits. Thats' because each child event holds
parent reference.

We want to release all children events once the parent is gone,
because at that time there's no process to read them anyway, so
they're just eating resources.

This removal  races with process exit, which removes all events
and fork, which clone events.  To be clear of those two, adding
work queue to remove orphaned child for context in case such
event is detected.

Using delayed work queue (with delay == 1), because we queue this
work under perf scheduler callbacks. Normal work queue tries to wake
up the queue process, which deadlocks on rq->lock in this place.

Also preventing clones from abandoned parent event.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406896382-18404-4-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 07:51:04 +02:00
Jiri Olsa
f86977620e perf: Set owner pointer for kernel events
Adding fake EVENT_OWNER_KERNEL owner pointer value for kernel perf
events, so we could distinguish it from user events, which needs
special care in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406896382-18404-3-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 07:51:03 +02:00
Vasant Hegde
14c4000a88 printk: Add function to return log buffer address and size
Platforms like IBM Power Systems supports service processor
assisted dump. It provides interface to add memory region to
be captured when system is crashed.

During initialization/running we can add kernel memory region
to be collected.

Presently we don't have a way to get the log buffer base address
and size. This patch adds support to return log buffer address
and size.

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
2014-08-13 15:13:44 +10:00
Rik van Riel
83d7f24247 sched/numa: Fix numa capacity computation
Commit c61037e9 fixes the phenomenon of 'fantom' cores due to
N*frac(smt_power) >= 1 by limiting the capacity to the actual
number of cores in the load balancing code.

This patch applies the same correction to the NUMA balancing
code.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: mgorman@suse.de
Cc: vincent.guittot@linaro.org
Cc: Morten.Rasmussen@arm.com
Cc: nicolas.pitre@linaro.org
Cc: efault@gmx.de
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1407173008-9334-3-git-send-email-riel@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-12 12:48:23 +02:00
Rik van Riel
b932c03c34 sched/numa: Fix off-by-one in capacity check
Commit a43455a1d5 ensures that
task_numa_migrate will call task_numa_compare on the preferred
node all the time, even when the preferred node has no free capacity.

This could lead to a performance regression if nr_running == capacity
on both the source and the destination node. This can be avoided by
also checking for nr_running == capacity on the source node, which is
one stricter than checking .has_free_capacity.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: mgorman@suse.de
Cc: vincent.guittot@linaro.org
Cc: Morten.Rasmussen@arm.com
Cc: nicolas.pitre@linaro.org
Cc: efault@gmx.de
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1407173008-9334-2-git-send-email-riel@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-12 12:48:22 +02:00
Zhihui Zhang
aaecac4ad4 sched: Rename a misleading variable in build_overlap_sched_groups()
The child variable in build_overlap_sched_groups() actually refers to the
peer or sibling domain of the given CPU. Rename it to sibling to be consistent
with the naming in build_group_mask().

Signed-off-by: Zhihui Zhang <zzhsuny@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1406942283-18249-1-git-send-email-zzhsuny@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-12 12:48:21 +02:00
Peter Zijlstra
9a5d9ba6a3 sched/fair: Allow calculate_imbalance() to move idle cpus
Allow calculate_imbalance() to 'create' idle cpus in the busiest group
if there are idle cpus in the local group.

Suggested-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140729152705.GX12054@laptop.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-12 12:48:20 +02:00
Rik van Riel
caeb178c60 sched/fair: Make update_sd_pick_busiest() return 'true' on a busier sd
Currently update_sd_pick_busiest only identifies the busiest sd
that is either overloaded, or has a group imbalance. When no
sd is imbalanced or overloaded, the load balancer fails to find
the busiest domain.

This breaks load balancing between domains that are not overloaded,
in the !SD_ASYM_PACKING case. This patch makes update_sd_pick_busiest
return true when the busiest sd yet is encountered.

Groups are ranked in the order overloaded > imbalanced > other,
with higher ranked groups getting priority even when their load
is lower. This is necessary due to the possibility of unequal
capacities and cpumasks between domains within a sched group.

Behaviour for SD_ASYM_PACKING does not seem to match the comment,
but I have no hardware to test that so I have left the behaviour
of that code unchanged.

Enum for group classification suggested by Peter Zijlstra.

Signed-off-by: Rik van Riel <riel@redhat.com>
[peterz: replaced sg_lb_stats::group_imb with the new enum group_type
         in an attempt to avoid endless recalculation]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Michael Neuling <mikey@neuling.org>
Cc: ktkhai@parallels.com
Cc: tim.c.chen@linux.intel.com
Cc: nicolas.pitre@linaro.org
Cc: jhladky@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140729152743.GI3935@laptop
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-12 12:48:19 +02:00
Peter Zijlstra
743cb1ff19 sched/fair: Make calculate_imbalance() independent
Rik noticed that calculate_imbalance() relies on
update_sd_pick_busiest() to guarantee that busiest->sum_nr_running >
busiest->group_capacity_factor.

Break this implicit assumption (with the intent of not providing it
anymore) by having calculat_imbalance() verify it and not rely on
others.

Reported-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20140729152631.GW12054@laptop.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-12 12:48:18 +02:00
Rafael J. Wysocki
e67ee10190 Merge branches 'pm-sleep', 'pm-cpufreq' and 'pm-cpuidle'
* pm-sleep:
  PM / hibernate: avoid unsafe pages in e820 reserved regions

* pm-cpufreq:
  cpufreq: arm_big_little: fix module license spec
  cpufreq: speedstep-smi: fix decimal printf specifiers
  cpufreq: OPP: Avoid sleeping while atomic
  cpufreq: cpu0: Do not print error message when deferring
  cpufreq: integrator: Use set_cpus_allowed_ptr

* pm-cpuidle:
  cpuidle: menu: Lookup CPU runqueues less
  cpuidle: menu: Call nr_iowait_cpu less times
  cpuidle: menu: Use ktime_to_us instead of reinventing the wheel
  cpuidle: menu: Use shifts when calculating averages where possible
2014-08-11 23:19:48 +02:00
Guenter Roeck
69f6a34bde seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock
Current upstream kernel hangs with mips and powerpc targets in
uniprocessor mode if SECCOMP is configured.

Bisect points to commit dbd952127d ("seccomp: introduce writer locking").
Turns out that code such as
	BUG_ON(!spin_is_locked(&list_lock));
can not be used in uniprocessor mode because spin_is_locked() always
returns false in this configuration, and that assert_spin_locked()
exists for that very purpose and must be used instead.

Fixes: dbd952127d ("seccomp: introduce writer locking")
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
2014-08-11 13:29:12 -07:00