Pull cgroup fixes from Tejun Heo:
- Fix for yet another xattr bug which may lead to NULL deref.
- A subtle bug in for_each_descendant_pre(). This bug requires quite
specific conditions to trigger and isn't too likely to actually
happen in the wild, but maybe that just makes it that much more
nastier.
- A warning message added for silly cgroup re-mount (not -o remount,
but unmount followed by mount) behavior.
* 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: warn about mismatching options of a new mount of an existing hierarchy
cgroup: fix a subtle bug in descendant pre-order walk
cgroup: initialize xattr before calling d_instantiate()
Since 7300711e ("clockevents: broadcast fixup possible waiters"),
the timekeeping duty is assigned to the CPU that handles the tick
broadcast clock device by the time it is set in one shot mode.
This is an issue in full dynticks mode where the timekeeping duty
must stay handled by the boot CPU for now. Otherwise it prevents
secondary CPUs from offlining and this breaks
suspend/shutdown/reboot/...
As it appears there is no reason for this timekeeping duty to be
moved to the broadcast CPU, besides nothing prevent it from being
later re-assigned to another target, let's simply remove it.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 78becc2709 ("sched: Use an accessor to read the rq clock")
introduces rq_clock(), which obsoletes the use of the "rq" variable
in expire_cfs_rq_runtime() and triggers this build warning:
kernel/sched/fair.c: In function 'expire_cfs_rq_runtime':
kernel/sched/fair.c:2159:13: warning: unused variable 'rq' [-Wunused-variable]
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul Turner <pjt@google.com>
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1369904660-14169-1-git-send-email-kamalesh@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In tick_nohz_cpu_down_callback() if the cpu is the one handling
timekeeping, we must return something that stops the CPU_DOWN_PREPARE
notifiers and then start notify CPU_DOWN_FAILED on the already called
notifier call backs.
However traditional errno values are not handled by the notifier unless
these are encapsulated using errno_to_notifier().
Hence the current -EINVAL is misinterpreted and converted to junk after
notifier_to_errno(), leaving the notifier subsystem to random behaviour
such as eventually allowing the cpu to go down.
Fix this by using the standard NOTIFY_BAD instead.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: 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>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The kvm_host.h header file doesn't handle well
inclusion when archs don't support KVM.
This results in build crashes for such archs when they
want to implement context tracking because this subsystem
includes kvm_host.h in order to implement the
guest_enter/exit APIs but it doesn't handle KVM off case.
To fix this, move the guest_enter()/guest_exit()
declarations and generic implementation to the context
tracking headers. These generic APIs actually belong to
this subsystem, besides other domains boundary tracking
like user_enter() et al.
KVM now properly becomes a user of this library, not the
other buggy way around.
Reported-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While computing the cputime delta of dynticks CPUs,
we are mixing up clocks of differents natures:
* local_clock() which takes care of unstable clock
sources and fix these if needed.
* sched_clock() which is the weaker version of
local_clock(). It doesn't compute any fixup in case
of unstable source.
If the clock source is stable, those two clocks are the
same and we can safely compute the difference against
two random points.
Otherwise it results in random deltas as sched_clock()
can randomly drift away, back or forward, from local_clock().
As a consequence, some strange behaviour with unstable tsc
has been observed such as non progressing constant zero cputime.
(The 'top' command showing no load).
Fix this by only using local_clock(), or its irq safe/remote
equivalent, in vtime code.
Reported-by: Mike Galbraith <efault@gmx.de>
Suggested-by: Mike Galbraith <efault@gmx.de>
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>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Peter Anvin:
- Three EFI-related fixes
- Two early memory initialization fixes
- build fix for older binutils
- fix for an eager FPU performance regression -- currently we don't
allow the use of the FPU at interrupt time *at all* in eager mode,
which is clearly wrong.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Allow FPU to be used at interrupt time even with eagerfpu
x86, crc32-pclmul: Fix build with older binutils
x86-64, init: Fix a possible wraparound bug in switchover in head_64.S
x86, range: fix missing merge during add range
x86, efi: initial the local variable of DataSize to zero
efivar: fix oops in efivar_update_sysfs_entries() caused by memory reuse
efivarfs: Never return ENOENT from firmware again
The branch selftest calls trace_test_buffer(), but with the new code
it expects the first parameter to be a pointer to a struct trace_buffer.
All self tests were changed but the branch selftest was missed.
This caused either a crash or failed test when the branch selftest was
enabled.
Link: http://lkml.kernel.org/r/20130529141333.GA24064@localhost
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Below is a patch from android kernel that maintains a histogram of
suspend times. Please review and provide feedback.
Statistices on the time spent in suspend are kept in
/sys/kernel/debug/sleep_time.
Cc: Android Kernel Team <kernel-team@android.com>
Cc: Colin Cross <ccross@android.com>
Cc: Todd Poynor <toddpoynor@google.com>
Cc: San Mehat <san@google.com>
Cc: Benoit Goby <benoit@android.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
[zoran.markovic@linaro.org: Re-formatted suspend time table to better
fit expected values. Moved accounting of suspend time into timekeeping
core. Removed CONFIG_SUSPEND_TIME flag and made the feature conditional
on CONFIG_DEBUG_FS. Changed the file name to sleep_time to better fit
terminology in timekeeping core. Changed seq_printf to seq_puts. Tweaked
commit message]
Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Add functions needed for hooking up alarmtimer to timerfd:
* alarm_restart: Similar to hrtimer_restart, restart an alarmtimer after
the expires time has already been updated (as with alarm_forward).
* alarm_forward_now: Similar to hrtimer_forward_now, move the expires
time forward to an interval from the current time of the associated clock.
* alarm_start_relative: Start an alarmtimer with an expires time relative to
the current time of the associated clock.
* alarm_expires_remaining: Similar to hrtimer_expires_remaining, return the
amount of time remaining until alarm expiry.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Some controllers have irqs that aren't wired up and must never be used.
For the generic chip attached to an irq_domain this provides a mask that
can be used to block out particular irqs so that they never get mapped.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1369793454-19197-2-git-send-email-grant.likely@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Provide infrastructure for irq chip implementations which work on
linear irq domains.
- Interface to allocate multiple generic chips which are associated to
the irq domain.
- Interface to get the generic chip pointer for a particular hardware
interrupt in the domain.
- irq domain mapping function to install the chip for a particular
interrupt.
Note: This lacks a removal function for now.
[ Sebastian Hesselbarth: Mask cache and pointer math fixups ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20130506142539.450634298@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Preparatory patch for linear interrupt domains.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20130506142539.377017672@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Some chips have weird bit mask access patterns instead of the linear
you expect. Allow them to calculate the cached mask themself.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20130506142539.302898834@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cache the per irq bit mask instead of recalculating it over and over.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20130506142539.227119865@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There are cases where all irq_chip_type instances have separate mask
registers, making a shared mask register cache unsuitable for the
purpose.
Introduce a new flag IRQ_GC_MASK_CACHE_PER_TYPE. If set, point the per
chip mask pointer to the per chip private mask cache instead.
[ tglx: Simplified code, renamed flag and massaged changelog ]
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Joey Oravec <joravec@drewtech.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Holger Brunck <Holger.Brunck@keymile.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Simon Guinot <simon@sequanux.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: Nicolas Pitre <nico@fluxnic.net>
Cc: Rob Landley <rob@landley.net>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/20130506142539.152569748@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Today the same interrupt mask cache (stored within struct irq_chip_generic)
is shared between all the irq_chip_type instances. As there are instances
where each irq_chip_type uses a distinct mask register (as it is the case
for Orion SoCs), sharing a single mask cache may be incorrect.
So add a distinct pointer for each irq_chip_type, which for now
points to the original mask register within irq_chip_generic.
So no functional changes here.
[ tglx: Minor cosmetic tweaks ]
Reported-by: Joey Oravec <joravec@drewtech.com>
Signed-off-by: Simon Guinot <sguinot@lacie.com>
Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Holger Brunck <Holger.Brunck@keymile.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Simon Guinot <simon@sequanux.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: Nicolas Pitre <nico@fluxnic.net>
Cc: Rob Landley <rob@landley.net>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/20130506142539.082226607@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Since we already have an irq_data_get_chip_type() function which returns
a pointer to irq_chip_type, use that instead of cur_regs().
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Joey Oravec <joravec@drewtech.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Holger Brunck <Holger.Brunck@keymile.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Simon Guinot <simon@sequanux.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: Nicolas Pitre <nico@fluxnic.net>
Cc: Rob Landley <rob@landley.net>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/20130506142539.010164766@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As rcu_dereference_raw() under RCU debug config options can add quite a
bit of checks, and that tracing uses rcu_dereference_raw(), these checks
happen with the function tracer. The function tracer also happens to trace
these debug checks too. This added overhead can livelock the system.
Have the function tracer use the new RCU _notrace equivalents that do
not do the debug checks for RCU.
Link: http://lkml.kernel.org/r/20130528184209.467603904@goodmis.org
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
With the new __DEVEL__sane_behavior mount option was introduced,
if the root cgroup is alive with no xattr function, to mount a
new cgroup with xattr will be rejected in terms of design which
just fine. However, if the root cgroup does not mounted with
__DEVEL__sane_hehavior, to create a new cgroup with xattr option
will succeed although after that the EA function does not works
as expected but will get ENOTSUPP for setting up attributes under
either cgroup. e.g.
setfattr: /cgroup2/test: Operation not supported
Instead of keeping silence in this case, it's better to drop a log
entry in warning level. That would be helpful to understand the
reason behind the scene from the user's perspective, and this is
essentially an improvement does not break the backward compatibilities.
With this fix, above mount attemption will keep up works as usual but
the following line cound be found at the system log:
[ ...] cgroup: new mount options do not match the existing superblock
tj: minor formatting / message updates.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Since commit 31ade30692, timekeeping_init()
checks for presence of persistent clock by attempting to read a non-zero
time value. This is an issue on platforms where persistent_clock (instead
is implemented as a free-running counter (instead of an RTC) starting
from zero on each boot and running during suspend. Examples are some ARM
platforms (e.g. PandaBoard).
An attempt to read such a clock during timekeeping_init() may return zero
value and falsely declare persistent clock as missing. Additionally, in
the above case suspend times may be accounted twice (once from
timekeeping_resume() and once from rtc_resume()), resulting in a gradual
drift of system time.
This patch does a run-time correction of the issue by doing the same check
during timekeeping_suspend().
A better long-term solution would have to return error when trying to read
non-existing clock and zero when trying to read an uninitialized clock, but
that would require changing all persistent_clock implementations.
This patch addresses the immediate breakage, for now.
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org>
[jstultz: Tweaked commit message and subject]
Signed-off-by: John Stultz <john.stultz@linaro.org>
kernel/time/ntp.c: In function ‘__hardpps’:
kernel/time/ntp.c:877: warning: unused variable ‘flags’
commit a076b2146f ("ntp: Remove ntp_lock,
using the timekeeping locks to protect ntp state") removed its users,
but not the actual variable.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The first one was reported by Mauro Carvalho Chehab, where if a poll()
is done against a trace buffer for a CPU that has never been online,
it will crash the kernel, as buffers are only created when a CPU comes
on line, but the trace files are for all possible CPUs.
This fix is to check if the buffer was allocated and if not return -EINVAL.
That was the simple fix, the real fix is a bit more complex and not for
a -rc release. We could have the files created when the CPUs come online.
That would require some design changes.
The second one was reported by Peter Zijlstra. If the kernel command line
has ftrace=nop, it will lock up the system on boot up. This is because
the new design for 3.10 has the nop tracer bootstrap the tracing subsystem.
When ftrace=<trace> is defined, when a that tracer is registered, it
starts the tracing, but uses the nop tracer to clear things out.
What happened here was that ftrace=nop caused the registering of nop
to start it and use nop before it was initialized.
The only thing nop needs to have done to initialize it is to have the
tracer point its current_tracer structure member to the nop tracer.
Doing that before registering the nop tracer makes everything work.
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Merge tag 'trace-fixes-v3.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two more fixes:
The first one was reported by Mauro Carvalho Chehab, where if a poll()
is done against a trace buffer for a CPU that has never been online,
it will crash the kernel, as buffers are only created when a CPU comes
on line, but the trace files are for all possible CPUs.
This fix is to check if the buffer was allocated and if not return
-EINVAL.
That was the simple fix, the real fix is a bit more complex and not
for a -rc release. We could have the files created when the CPUs come
online. That would require some design changes.
The second one was reported by Peter Zijlstra. If the kernel command
line has ftrace=nop, it will lock up the system on boot up. This is
because the new design for 3.10 has the nop tracer bootstrap the
tracing subsystem. When ftrace=<trace> is defined, when a that tracer
is registered, it starts the tracing, but uses the nop tracer to clear
things out. What happened here was that ftrace=nop caused the
registering of nop to start it and use nop before it was initialized.
The only thing nop needs to have done to initialize it is to have the
tracer point its current_tracer structure member to the nop tracer.
Doing that before registering the nop tracer makes everything work."
* tag 'trace-fixes-v3.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Do not poll non allocated cpu buffers
tracing: Fix crash when ftrace=nop on the kernel command line
The tracing infrastructure sets up for possible CPUs, but it uses
the ring buffer polling, it is possible to call the ring buffer
polling code with a CPU that hasn't been allocated. This will cause
a kernel oops when it access a ring buffer cpu buffer that is part
of the possible cpus but hasn't been allocated yet as the CPU has never
been online.
Reported-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In old kernels, it's allowed to set softlockup_thresh to -1 or 0
to disable softlockup detection. However watchdog_thresh only
uses 0 to disable detection, and setting it to -1 just froze my
box and nothing I can do but reboot.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/51959668.9040106@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vince reported a problem found by his perf specific trinity
fuzzer.
Al noticed 2 problems with perf's mmap():
- it has issues against fork() since we use vma->vm_mm for accounting.
- it has an rb refcount leak on double mmap().
We fix the issues against fork() by using VM_DONTCOPY; I don't
think there's code out there that uses this; we didn't hear
about weird accounting problems/crashes. If we do need this to
work, the previously proposed VM_PINNED could make this work.
Aside from the rb reference leak spotted by Al, Vince's example
prog was indeed doing a double mmap() through the use of
perf_event_set_output().
This exposes another problem, since we now have 2 events with
one buffer, the accounting gets screwy because we account per
event. Fix this by making the buffer responsible for its own
accounting.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/20130528085548.GA12193@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix to free gone and unused optprobes. This bug will
cause a kernel panic if the user reuses the killed and
unused probe.
Reported at:
http://sourceware.org/ml/systemtap/2013-q2/msg00142.html
In the normal path, an optprobe on an init function is
unregistered when a module goes live.
unregister_kprobe(kp)
-> __unregister_kprobe_top
->__disable_kprobe
->disarm_kprobe(ap == op)
->__disarm_kprobe
->unoptimize_kprobe : the op is queued
on unoptimizing_list
and do nothing in __unregister_kprobe_bottom
After a while (usually wait 5 jiffies), kprobe_optimizer
runs to unoptimize and free optprobe.
kprobe_optimizer
->do_unoptimize_kprobes
->arch_unoptimize_kprobes : moved to free_list
->do_free_cleaned_kprobes
->hlist_del: the op is removed
->free_aggr_kprobe
->arch_remove_optimized_kprobe
->arch_remove_kprobe
->kfree: the op is freed
Here, if kprobes_module_callback is called and the delayed
unoptimizing probe is picked BEFORE kprobe_optimizer runs,
kprobes_module_callback
->kill_kprobe
->kill_optimized_kprobe : dequeued from unoptimizing_list <=!!!
->arch_remove_optimized_kprobe
->arch_remove_kprobe
(but op is not freed, and on the kprobe hash table)
This doesn't happen if the probe unregistration is done AFTER
kprobes_module_callback is called (because at that time the op
is gone), and kprobe-tracer does it.
To fix this bug, this patch changes kprobes_module_callback to
enqueue the op to freeing_list at kill_optimized_kprobe only
if the op is unused. The unused probes on freeing_list will
be freed in do_free_cleaned_kprobes.
Note that this calls arch_remove_*kprobe twice on the
same probe. Thus those functions have to check the double free.
Fortunately, most of arch codes already checked that except
for mips. This will be fixed in the next patch.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Timo Juhani Lindfors <timo.lindfors@iki.fi>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: systemtap@sourceware.org
Cc: yrl.pp-manager.tt@hitachi.com
Cc: David S. Miller <davem@davemloft.net>
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20130522093409.9084.63554.stgit@mhiramat-M0-7522
[ Minor edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
commit 7eaeb34305 (clocksource: Provide unbind interface in sysfs)
implemented clocksource_select_fallback() which is not defined for
CONFIG_ARCH_USES_GETTIMEOFFSET=y. Add an empty inline function for
that.
Reported-by: Ingo Molnar <mingo@kernel.org>
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Read the runqueue clock through an accessor. This
prepares for adding a debugging infrastructure to
detect missing or redundant calls to update_rq_clock()
between a scheduler's entry and exit point.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365724262-20142-6-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In this function we are making use of rq->clock right before the
update of the rq clock, let's just call update_rq_clock() just
before that to avoid using a stale rq clock value.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365724262-20142-5-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
check_preempt_curr() of fair class needs an uptodate sched clock
value to update runtime stats of the current task of the target's rq.
When a task is woken up, activate_task() is usually called right before
ttwu_do_wakeup() unless the task is still in the runqueue. In the latter
case we need to update the rq clock explicitly because activate_task()
isn't here to do the job for us.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365724262-20142-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Because we may update the execution time in
sched_group_set_shares()->update_cfs_shares()->reweight_entity()->update_curr()
before reweighting the entity while setting the group shares and this requires
an uptodate version of the runqueue clock.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365724262-20142-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Because the sched_class::put_prev_task() callback of rt and fair
classes are referring to the rq clock to update their runtime
statistics. There is a missing rq clock update from the CPU
hotplug notifier's entry point of the scheduler.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365724262-20142-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
migration_call() will do all the things that update_runtime() does.
So let's remove it.
Furthermore, there is potential risk that the current code will catch
BUG_ON at line 689 of rt.c when do cpu hotplug while there are realtime
threads running because of enabling runtime twice while the rt_runtime
may already changed.
Signed-off-by: Neil Zhang <zhangwm@marvell.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1365685499-26515-1-git-send-email-zhangwm@marvell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In autogroup_create(), a tg is allocated and added to the task_groups
list. If CONFIG_RT_GROUP_SCHED is set, this tg is then modified while on
the list, without locking. This can race with someone walking the list,
like __enable_runtime() during CPU unplug, and result in a use-after-free
bug.
To fix this, move sched_online_group(), which adds the tg to the list,
to the end of the autogroup_create() function after the modification.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1369411669-46971-2-git-send-email-gerald.schaefer@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
commit 26517f3e (tick: Avoid programming the local cpu timer if
broadcast pending) added a warning if the cpu enters broadcast mode
again while the pending bit is still set. Meelis reported that the
warning triggers. There are two corner cases which have been not
considered:
1) cpuidle calls clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER)
twice. That can result in the following scenario
CPU0 CPU1
cpuidle_idle_call()
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER)
set cpu in tick_broadcast_oneshot_mask
broadcast interrupt
event expired for cpu1
set pending bit
acpi_idle_enter_simple()
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER)
WARN_ON(pending bit)
Move the WARN_ON into the section where we enter broadcast mode so
it wont provide false positives on the second call.
2) safe_halt() enables interrupts, so a broadcast interrupt can be
delivered befor the broadcast mode is disabled. That sets the
pending bit for the CPU which receives the broadcast
interrupt. Though the interrupt is delivered right away from the
broadcast handler and leaves the pending bit stale.
Clear the pending bit for the current cpu in the broadcast handler.
Reported-and-tested-by: Meelis Roos <mroos@linux.ee>
Cc: Len Brown <lenb@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305271841130.4220@ionos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Unbreak architectures which do not use clockevents, but require to
build some of the core timekeeping infrastructure
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Parameters and usage of rt_mutex_adjust_prio_chain() are already
documented in Documentation/rt-mutex-design.txt. However, since this
function is called from several paths with different semantics (related
to the arguments), it is handy to have a quick reference directly in
the code.
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1368608650-7935-1-git-send-email-juri.lelli@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch moves commit 7cc23cd to the generic code:
perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL
The check is now implemented in generic code instead of x86 specific
code. That way we do not have to repeat the test in each arch
supporting branch sampling.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/20130521105337.GA2879@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch adds /sys/device/xxx/perf_event_mux_interval_ms to ajust
the multiplexing interval per PMU. The unit is milliseconds. Value has
to be >= 1.
In the 4th version, we renamed the sysfs file to be more consistent
with the other /proc/sys/kernel entries for perf_events.
In the 5th version, we handle the reprogramming of the hrtimer using
hrtimer_forward_now(). That way, we sync up to new timer value quickly
(suggested by Jiri Olsa).
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/1364991694-5876-3-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
The hw breakpoint pmu 'add' function is missing the
period_left update needed for SW events.
The perf HW breakpoint events use the SW events framework
to process the overflow, so it needs to be properly initialized
in the PMU 'add' method.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Reviewed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1367421944-19082-5-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Kconfig symbols ARCH_INLINE_READ_UNLOCK_IRQ,
ARCH_INLINE_SPIN_UNLOCK_IRQ, and ARCH_INLINE_WRITE_UNLOCK_IRQ were added
in v2.6.33, but have never actually been used. Ingo Molnar spotted that
this is caused by three identical copy/paste erros. Eg, the Kconfig
entry for
INLINE_READ_UNLOCK_IRQ
has an (optional) dependency on:
ARCH_INLINE_READ_UNLOCK_BH
were it apparently should depend on:
ARCH_INLINE_READ_UNLOCK_IRQ
instead. Likewise for the Kconfig entries for INLINE_SPIN_UNLOCK_IRQ and
INLINE_WRITE_UNLOCK_IRQ. Fix these three errors.
This never really caused any real problems as these symbols are set (or
unset) in a group - but it's worth fixing it nevertheless.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1368780693.1350.228.camel@x61.thuisdomein
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix kernel-doc warnings in kernel/auditfilter.c:
Warning(kernel/auditfilter.c:1029): Excess function parameter 'loginuid' description in 'audit_receive_filter'
Warning(kernel/auditfilter.c:1029): Excess function parameter 'sessionid' description in 'audit_receive_filter'
Warning(kernel/auditfilter.c:1029): Excess function parameter 'sid' description in 'audit_receive_filter'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
result in event_enable_func(). After checking the return status
of try_module_get(), it returned the status of try_module_get(). But
try_module_get() returns 0 on failure, which is success for
event_enable_func().
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Merge tag 'trace-fixes-v3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Masami Hiramatsu fixed another bug. This time returning a proper
result in event_enable_func(). After checking the return status of
try_module_get(), it returned the status of try_module_get().
But try_module_get() returns 0 on failure, which is success for
event_enable_func()"
* tag 'trace-fixes-v3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Return -EBUSY when event_enable_func() fails to get module
This patch converts cgroup_for_each_child(),
cgroup_next_descendant_pre/post() and thus
cgroup_for_each_descendant_pre/post() to use cgroup_next_sibling()
instead of manually dereferencing ->sibling.next.
The only reason the iterators couldn't allow dropping RCU read lock
while iteration is in progress was because they couldn't determine the
next sibling safely once RCU read lock is dropped. Using
cgroup_next_sibling() removes that problem and enables all iterators
to allow dropping RCU read lock in the middle. Comments are updated
accordingly.
This makes the iterators easier to use and will simplify controllers.
Note that @cgroup argument is renamed to @cgrp in
cgroup_for_each_child() because it conflicts with "struct cgroup" used
in the new macro body.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
