Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-6-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Collection of aesthetic adjustments to various PPS-related files,
directories and Documentation, some quite minor just for the sake of
consistency, including:
* Updated example of pps device tree node (courtesy Rodolfo G.)
* "PPS-API" -> "PPS API"
* "pps_source_info_s" -> "pps_source_info"
* "ktimer driver" -> "pps-ktimer driver"
* "ppstest /dev/pps0" -> "ppstest /dev/pps1" to match example
* Add missing PPS-related entries to MAINTAINERS file
* Other trivialities
Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1708261048220.8106@localhost.localdomain
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Drop the P-state selection algorithm based on a PID controller
from intel_pstate and make it use the same P-state selection
method (based on the CPU load) for all types of systems in the
active mode (Rafael Wysocki, Srinivas Pandruvada).
- Rework the cpufreq core and governors to make it possible to
take cross-CPU utilization updates into account and modify the
schedutil governor to actually do so (Viresh Kumar).
- Clean up the handling of transition latency information in the
cpufreq core and untangle it from the information on which drivers
cannot do dynamic frequency switching (Viresh Kumar).
- Add support for new SoCs (MT2701/MT7623 and MT7622) to the
mediatek cpufreq driver and update its DT bindings (Sean Wang).
- Modify the cpufreq dt-platdev driver to autimatically create
cpufreq devices for the new (v2) Operating Performance Points
(OPP) DT bindings and update its whitelist of supported systems
(Viresh Kumar, Shubhrajyoti Datta, Marc Gonzalez, Khiem Nguyen,
Finley Xiao).
- Add support for Ux500 to the cpufreq-dt driver and drop the
obsolete dbx500 cpufreq driver (Linus Walleij, Arnd Bergmann).
- Add new SoC (R8A7795) support to the cpufreq rcar driver (Khiem
Nguyen).
- Fix and clean up assorted issues in the cpufreq drivers and core
(Arvind Yadav, Christophe Jaillet, Colin Ian King, Gustavo Silva,
Julia Lawall, Leonard Crestez, Rob Herring, Sudeep Holla).
- Update the IO-wait boost handling in the schedutil governor to
make it less aggressive (Joel Fernandes).
- Rework system suspend diagnostics to make it print fewer messages
to the kernel log by default, add a sysfs knob to allow more
suspend-related messages to be printed and add Low Power S0 Idle
constraints checks to the ACPI suspend-to-idle code (Rafael
Wysocki, Srinivas Pandruvada).
- Prefer suspend-to-idle over S3 on ACPI-based systems with the
ACPI_FADT_LOW_POWER_S0 flag set and the Low Power Idle S0 _DSM
interface present in the ACPI tables (Rafael Wysocki).
- Update documentation related to system sleep and rename a number
of items in the code to make it cleare that they are related to
suspend-to-idle (Rafael Wysocki).
- Export a variable allowing device drivers to check the target
system sleep state from the core system suspend code (Florian
Fainelli).
- Clean up the cpuidle subsystem to handle the polling state on
x86 in a more straightforward way and to use %pOF instead of
full_name (Rafael Wysocki, Rob Herring).
- Update the devfreq framework to fix and clean up a few minor
issues (Chanwoo Choi, Rob Herring).
- Extend diagnostics in the generic power domains (genpd) framework
and clean it up slightly (Thara Gopinath, Rob Herring).
- Fix and clean up a couple of issues in the operating performance
points (OPP) framework (Viresh Kumar, Waldemar Rymarkiewicz).
- Add support for RV1108 to the rockchip-io Adaptive Voltage Scaling
(AVS) driver (David Wu).
- Fix the usage of notifiers in CPU power management on some
platforms (Alex Shi).
- Update the pm-graph system suspend/hibernation and boot profiling
utility (Todd Brandt).
- Make it possible to run the cpupower utility without CPU0 (Prarit
Bhargava).
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Merge tag 'pm-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"This time (again) cpufreq gets the majority of changes which mostly
are driver updates (including a major consolidation of intel_pstate),
some schedutil governor modifications and core cleanups.
There also are some changes in the system suspend area, mostly related
to diagnostics and debug messages plus some renames of things related
to suspend-to-idle. One major change here is that suspend-to-idle is
now going to be preferred over S3 on systems where the ACPI tables
indicate to do so and provide requsite support (the Low Power Idle S0
_DSM in particular). The system sleep documentation and the tools
related to it are updated too.
The rest is a few cpuidle changes (nothing major), devfreq updates,
generic power domains (genpd) framework updates and a few assorted
modifications elsewhere.
Specifics:
- Drop the P-state selection algorithm based on a PID controller from
intel_pstate and make it use the same P-state selection method
(based on the CPU load) for all types of systems in the active mode
(Rafael Wysocki, Srinivas Pandruvada).
- Rework the cpufreq core and governors to make it possible to take
cross-CPU utilization updates into account and modify the schedutil
governor to actually do so (Viresh Kumar).
- Clean up the handling of transition latency information in the
cpufreq core and untangle it from the information on which drivers
cannot do dynamic frequency switching (Viresh Kumar).
- Add support for new SoCs (MT2701/MT7623 and MT7622) to the mediatek
cpufreq driver and update its DT bindings (Sean Wang).
- Modify the cpufreq dt-platdev driver to autimatically create
cpufreq devices for the new (v2) Operating Performance Points (OPP)
DT bindings and update its whitelist of supported systems (Viresh
Kumar, Shubhrajyoti Datta, Marc Gonzalez, Khiem Nguyen, Finley
Xiao).
- Add support for Ux500 to the cpufreq-dt driver and drop the
obsolete dbx500 cpufreq driver (Linus Walleij, Arnd Bergmann).
- Add new SoC (R8A7795) support to the cpufreq rcar driver (Khiem
Nguyen).
- Fix and clean up assorted issues in the cpufreq drivers and core
(Arvind Yadav, Christophe Jaillet, Colin Ian King, Gustavo Silva,
Julia Lawall, Leonard Crestez, Rob Herring, Sudeep Holla).
- Update the IO-wait boost handling in the schedutil governor to make
it less aggressive (Joel Fernandes).
- Rework system suspend diagnostics to make it print fewer messages
to the kernel log by default, add a sysfs knob to allow more
suspend-related messages to be printed and add Low Power S0 Idle
constraints checks to the ACPI suspend-to-idle code (Rafael
Wysocki, Srinivas Pandruvada).
- Prefer suspend-to-idle over S3 on ACPI-based systems with the
ACPI_FADT_LOW_POWER_S0 flag set and the Low Power Idle S0 _DSM
interface present in the ACPI tables (Rafael Wysocki).
- Update documentation related to system sleep and rename a number of
items in the code to make it cleare that they are related to
suspend-to-idle (Rafael Wysocki).
- Export a variable allowing device drivers to check the target
system sleep state from the core system suspend code (Florian
Fainelli).
- Clean up the cpuidle subsystem to handle the polling state on x86
in a more straightforward way and to use %pOF instead of full_name
(Rafael Wysocki, Rob Herring).
- Update the devfreq framework to fix and clean up a few minor issues
(Chanwoo Choi, Rob Herring).
- Extend diagnostics in the generic power domains (genpd) framework
and clean it up slightly (Thara Gopinath, Rob Herring).
- Fix and clean up a couple of issues in the operating performance
points (OPP) framework (Viresh Kumar, Waldemar Rymarkiewicz).
- Add support for RV1108 to the rockchip-io Adaptive Voltage Scaling
(AVS) driver (David Wu).
- Fix the usage of notifiers in CPU power management on some
platforms (Alex Shi).
- Update the pm-graph system suspend/hibernation and boot profiling
utility (Todd Brandt).
- Make it possible to run the cpupower utility without CPU0 (Prarit
Bhargava)"
* tag 'pm-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (87 commits)
cpuidle: Make drivers initialize polling state
cpuidle: Move polling state initialization code to separate file
cpuidle: Eliminate the CPUIDLE_DRIVER_STATE_START symbol
cpufreq: imx6q: Fix imx6sx low frequency support
cpufreq: speedstep-lib: make several arrays static, makes code smaller
PM: docs: Delete the obsolete states.txt document
PM: docs: Describe high-level PM strategies and sleep states
PM / devfreq: Fix memory leak when fail to register device
PM / devfreq: Add dependency on PM_OPP
PM / devfreq: Move private devfreq_update_stats() into devfreq
PM / devfreq: Convert to using %pOF instead of full_name
PM / AVS: rockchip-io: add io selectors and supplies for RV1108
cpufreq: ti: Fix 'of_node_put' being called twice in error handling path
cpufreq: dt-platdev: Drop few entries from whitelist
cpufreq: dt-platdev: Automatically create cpufreq device with OPP v2
ARM: ux500: don't select CPUFREQ_DT
cpuidle: Convert to using %pOF instead of full_name
cpufreq: Convert to using %pOF instead of full_name
PM / Domains: Convert to using %pOF instead of full_name
cpufreq: Cap the default transition delay value to 10 ms
...
Pull timer fixes from Thomas Gleixner:
"A rather small update for the time(r) subsystem:
- A new clocksource driver IMX-TPM
- Minor fixes to the alarmtimer facility
- Device tree cleanups for Renesas drivers
- A new kselftest and fixes for the timer related tests
- Conversion of the clocksource drivers to use %pOF
- Use the proper helpers to access rlimits in the posix-cpu-timer
code"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
alarmtimer: Ensure RTC module is not unloaded
clocksource: Convert to using %pOF instead of full_name
clocksource/drivers/bcm2835: Remove message for a memory allocation failure
devicetree: bindings: Remove deprecated properties
devicetree: bindings: Remove unused 32-bit CMT bindings
devicetree: bindings: Deprecate property, update example
devicetree: bindings: r8a73a4 and R-Car Gen2 CMT bindings
devicetree: bindings: R-Car Gen2 CMT0 and CMT1 bindings
devicetree: bindings: Remove sh7372 CMT binding
clocksource/drivers/imx-tpm: Add imx tpm timer support
dt-bindings: timer: Add nxp tpm timer binding doc
posix-cpu-timers: Use dedicated helper to access rlimit values
alarmtimer: Fix unavailable wake-up source in sysfs
timekeeping: Use proper timekeeper for debug code
kselftests: timers: set-timer-lat: Add one-shot timer test cases
kselftests: timers: set-timer-lat: Tweak reporting when timer fires early
kselftests: timers: freq-step: Fix build warning
kselftests: timers: freq-step: Define ADJ_SETOFFSET if device has older kernel headers
* pm-sleep:
ACPI / PM: Check low power idle constraints for debug only
PM / s2idle: Rename platform operations structure
PM / s2idle: Rename ->enter_freeze to ->enter_s2idle
PM / s2idle: Rename freeze_state enum and related items
PM / s2idle: Rename PM_SUSPEND_FREEZE to PM_SUSPEND_TO_IDLE
ACPI / PM: Prefer suspend-to-idle over S3 on some systems
platform/x86: intel-hid: Wake up Dell Latitude 7275 from suspend-to-idle
PM / suspend: Define pr_fmt() in suspend.c
PM / suspend: Use mem_sleep_labels[] strings in messages
PM / sleep: Put pm_test under CONFIG_PM_SLEEP_DEBUG
PM / sleep: Check pm_wakeup_pending() in __device_suspend_noirq()
PM / core: Add error argument to dpm_show_time()
PM / core: Split dpm_suspend_noirq() and dpm_resume_noirq()
PM / s2idle: Rearrange the main suspend-to-idle loop
PM / timekeeping: Print debug messages when requested
PM / sleep: Mark suspend/hibernation start and finish
PM / sleep: Do not print debug messages by default
PM / suspend: Export pm_suspend_target_state
When registering the rtc device to be used to handle alarm timers,
get_device is used to ensure the device doesn't go away but the module can
still be unloaded.
Call try_module_get to ensure the rtc driver will not go away.
Reported-and-tested-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Link: http://lkml.kernel.org/r/20170820220146.30969-1-alexandre.belloni@free-electrons.com
In comqit fc6eead7c1 ("time: Clean up CLOCK_MONOTONIC_RAW time
handling"), the following code got mistakenly added to the update of the
raw timekeeper:
/* Update the monotonic raw base */
seconds = tk->raw_sec;
nsec = (u32)(tk->tkr_raw.xtime_nsec >> tk->tkr_raw.shift);
tk->tkr_raw.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
Which adds the raw_sec value and the shifted down raw xtime_nsec to the
base value.
But the read function adds the shifted down tk->tkr_raw.xtime_nsec value
another time, The result of this is that ktime_get_raw() users (which are
all internal users) see the raw time move faster then it should (the rate
at which can vary with the current size of tkr_raw.xtime_nsec), which has
resulted in at least problems with graphics rendering performance.
The change tried to match the monotonic base update logic:
seconds = (u64)(tk->xtime_sec + tk->wall_to_monotonic.tv_sec);
nsec = (u32) tk->wall_to_monotonic.tv_nsec;
tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
Which adds the wall_to_monotonic.tv_nsec value, but not the
tk->tkr_mono.xtime_nsec value to the base.
To fix this, simplify the tkr_raw.base accumulation to only accumulate the
raw_sec portion, and do not include the tkr_raw.xtime_nsec portion, which
will be added at read time.
Fixes: fc6eead7c1 ("time: Clean up CLOCK_MONOTONIC_RAW time handling")
Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Daniel Mentz <danielmentz@google.com>
Link: http://lkml.kernel.org/r/1503701824-1645-1-git-send-email-john.stultz@linaro.org
When a timer base is idle, it is forwarded when a new timer is added
to ensure that granularity does not become excessive. When not idle,
the timer tick is expected to increment the base.
However there are several problems:
- If an existing timer is modified, the base is forwarded only after
the index is calculated.
- The base is not forwarded by add_timer_on.
- There is a window after a timer is restarted from a nohz idle, after
it is marked not-idle and before the timer tick on this CPU, where a
timer may be added but the ancient base does not get forwarded.
These result in excessive granularity (a 1 jiffy timeout can blow out
to 100s of jiffies), which cause the rcu lockup detector to trigger,
among other things.
Fix this by keeping track of whether the timer base has been idle
since it was last run or forwarded, and if so then forward it before
adding a new timer.
There is still a case where mod_timer optimises the case of a pending
timer mod with the same expiry time, where the timer can see excessive
granularity relative to the new, shorter interval. A comment is added,
but it's not changed because it is an important fastpath for
networking.
This has been tested and found to fix the RCU softlockup messages.
Testing was also done with tracing to measure requested versus
achieved wakeup latencies for all non-deferrable timers in an idle
system (with no lockup watchdogs running). Wakeup latency relative to
absolute latency is calculated (note this suffers from round-up skew
at low absolute times) and analysed:
max avg std
upstream 506.0 1.20 4.68
patched 2.0 1.08 0.15
The bug was noticed due to the lockup detector Kconfig changes
dropping it out of people's .configs and resulting in larger base
clk skew When the lockup detectors are enabled, no CPU can go idle for
longer than 4 seconds, which limits the granularity errors.
Sub-optimal timer behaviour is observable on a smaller scale in that
case:
max avg std
upstream 9.0 1.05 0.19
patched 2.0 1.04 0.11
Fixes: Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: David Miller <davem@davemloft.net>
Cc: dzickus@redhat.com
Cc: sfr@canb.auug.org.au
Cc: mpe@ellerman.id.au
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: linuxarm@huawei.com
Cc: abdhalee@linux.vnet.ibm.com
Cc: John Stultz <john.stultz@linaro.org>
Cc: akpm@linux-foundation.org
Cc: paulmck@linux.vnet.ibm.com
Cc: torvalds@linux-foundation.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170822084348.21436-1-npiggin@gmail.com
Pull timekeepig updates from John Stultz
- kselftest improvements
- Use the proper timekeeper in the debug code
- Prevent accessing an unavailable wakeup source in the alarmtimer sysfs
interface.
Use rlimit() and rlimit_max() helper instead of manually writing
whole chain from task to rlimit value
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170705172548.7911-1-k.opasiak@samsung.com
Currently the alarmtimer registers a wake-up source unconditionally,
regardless of the system having a (wake-up capable) RTC or not.
Hence the alarmtimer will always show up in
/sys/kernel/debug/wakeup_sources, even if it is not available, and thus
cannot be a wake-up source.
To fix this, postpone registration until a wake-up capable RTC device is
added.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: John Stultz <john.stultz@linaro.org>
When CONFIG_DEBUG_TIMEKEEPING is enabled the timekeeping_check_update()
function will update status like last_warning and underflow_seen on the
timekeeper.
If there are issues found this state is used to rate limit the warnings
that get printed.
This rate limiting doesn't really really work if stored in real_tk as
the shadow timekeeper is overwritten onto real_tk at the end of every
update_wall_time() call, resetting last_warning and other statuses.
Fix rate limiting by using the shadow_timekeeper for
timekeeping_check_update().
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Fixes: commit 57d05a93ad ("time: Rework debugging variables so they aren't global")
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
For e.g. HZ=100, timer being 430 jiffies in the future, and 32 bit
unsigned int, there is an overflow on unsigned int right-hand side
of the expression which results with wrong values being returned.
Type cast the multiplier to 64bit to avoid that issue.
Fixes: 46c8f0b077 ("timers: Fix get_next_timer_interrupt() computation")
Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: khilman@baylibre.com
Cc: akpm@linux-foundation.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/a7900f04-2a21-c9fd-67be-ab334d459ee5@nokia.com
The messages printed by tk_debug_account_sleep_time() are basically
useful for system sleep debugging, so print them only when the other
debug messages from the core suspend/hibernate code are enabled.
While at it, make it clear that the messages from
tk_debug_account_sleep_time() are about timekeeping suspend
duration, because in general timekeeping may be suspeded and
resumed for multiple times during one system suspend-resume cycle.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull timer-related user access updates from Al Viro:
"Continuation of timers-related stuff (there had been more, but my
parts of that series are already merged via timers/core). This is more
of y2038 work by Deepa Dinamani, partially disrupted by the
unification of native and compat timers-related syscalls"
* 'timers-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
posix_clocks: Use get_itimerspec64() and put_itimerspec64()
timerfd: Use get_itimerspec64() and put_itimerspec64()
nanosleep: Use get_timespec64() and put_timespec64()
posix-timers: Use get_timespec64() and put_timespec64()
posix-stubs: Conditionally include COMPAT_SYS_NI defines
time: introduce {get,put}_itimerspec64
time: add get_timespec64 and put_timespec64
Pull timer updates from Thomas Gleixner:
"A rather large update for timers/timekeeping:
- compat syscall consolidation (Al Viro)
- Posix timer consolidation (Christoph Helwig / Thomas Gleixner)
- Cleanup of the device tree based initialization for clockevents and
clocksources (Daniel Lezcano)
- Consolidation of the FTTMR010 clocksource/event driver (Linus
Walleij)
- The usual set of small fixes and updates all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (93 commits)
timers: Make the cpu base lock raw
clocksource/drivers/mips-gic-timer: Fix an error code in 'gic_clocksource_of_init()'
clocksource/drivers/fsl_ftm_timer: Unmap region obtained by of_iomap
clocksource/drivers/tcb_clksrc: Make IO endian agnostic
clocksource/drivers/sun4i: Switch to the timer-of common init
clocksource/drivers/timer-of: Fix invalid iomap check
Revert "ktime: Simplify ktime_compare implementation"
clocksource/drivers: Fix uninitialized variable use in timer_of_init
kselftests: timers: Add test for frequency step
kselftests: timers: Fix inconsistency-check to not ignore first timestamp
time: Add warning about imminent deprecation of CONFIG_GENERIC_TIME_VSYSCALL_OLD
time: Clean up CLOCK_MONOTONIC_RAW time handling
posix-cpu-timers: Make timespec to nsec conversion safe
itimer: Make timeval to nsec conversion range limited
timers: Fix parameter description of try_to_del_timer_sync()
ktime: Simplify ktime_compare implementation
clocksource/drivers/fttmr010: Factor out clock read code
clocksource/drivers/fttmr010: Implement delay timer
clocksource/drivers: Add timer-of common init routine
clocksource/drivers/tcb_clksrc: Save timer context on suspend/resume
...
Pull nohz updates from Ingo Molnar:
"The main changes in this cycle relate to fixing another bad (but
sporadic and hard to detect) interaction between the dynticks
scheduler tick and hrtimers, plus related improvements to better
detection and handling of similar problems - by Frédéric Weisbecker"
* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
nohz: Fix spurious warning when hrtimer and clockevent get out of sync
nohz: Fix buggy tick delay on IRQ storms
nohz: Reset next_tick cache even when the timer has no regs
nohz: Fix collision between tick and other hrtimers, again
nohz: Add hrtimer sanity check
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle were:
- Add the SYSTEM_SCHEDULING bootup state to move various scheduler
debug checks earlier into the bootup. This turns silent and
sporadically deadly bugs into nice, deterministic splats. Fix some
of the splats that triggered. (Thomas Gleixner)
- A round of restructuring and refactoring of the load-balancing and
topology code (Peter Zijlstra)
- Another round of consolidating ~20 of incremental scheduler code
history: this time in terms of wait-queue nomenclature. (I didn't
get much feedback on these renaming patches, and we can still
easily change any names I might have misplaced, so if anyone hates
a new name, please holler and I'll fix it.) (Ingo Molnar)
- sched/numa improvements, fixes and updates (Rik van Riel)
- Another round of x86/tsc scheduler clock code improvements, in hope
of making it more robust (Peter Zijlstra)
- Improve NOHZ behavior (Frederic Weisbecker)
- Deadline scheduler improvements and fixes (Luca Abeni, Daniel
Bristot de Oliveira)
- Simplify and optimize the topology setup code (Lauro Ramos
Venancio)
- Debloat and decouple scheduler code some more (Nicolas Pitre)
- Simplify code by making better use of llist primitives (Byungchul
Park)
- ... plus other fixes and improvements"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
sched/cputime: Refactor the cputime_adjust() code
sched/debug: Expose the number of RT/DL tasks that can migrate
sched/numa: Hide numa_wake_affine() from UP build
sched/fair: Remove effective_load()
sched/numa: Implement NUMA node level wake_affine()
sched/fair: Simplify wake_affine() for the single socket case
sched/numa: Override part of migrate_degrades_locality() when idle balancing
sched/rt: Move RT related code from sched/core.c to sched/rt.c
sched/deadline: Move DL related code from sched/core.c to sched/deadline.c
sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled
sched/fair: Spare idle load balancing on nohz_full CPUs
nohz: Move idle balancer registration to the idle path
sched/loadavg: Generalize "_idle" naming to "_nohz"
sched/core: Drop the unused try_get_task_struct() helper function
sched/fair: WARN() and refuse to set buddy when !se->on_rq
sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well
sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c
sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h>
...
Pull RCU updates from Ingo Molnar:
"The sole purpose of these changes is to shrink and simplify the RCU
code base, which has suffered from creeping bloat over the past couple
of years. The end result is a net removal of ~2700 lines of code:
79 files changed, 1496 insertions(+), 4211 deletions(-)
Plus there's a marked reduction in the Kconfig space complexity as
well, here's the number of matches on 'grep RCU' in the .config:
before after
x86-defconfig 17 15
x86-allmodconfig 33 20"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits)
rcu: Remove RCU CPU stall warnings from Tiny RCU
rcu: Remove event tracing from Tiny RCU
rcu: Move RCU debug Kconfig options to kernel/rcu
rcu: Move RCU non-debug Kconfig options to kernel/rcu
rcu: Eliminate NOCBs CPU-state Kconfig options
rcu: Remove debugfs tracing
srcu: Remove Classic SRCU
srcu: Fix rcutorture-statistics typo
rcu: Remove SPARSE_RCU_POINTER Kconfig option
rcu: Remove the now-obsolete PROVE_RCU_REPEATEDLY Kconfig option
rcu: Remove typecheck() from RCU locking wrapper functions
rcu: Remove #ifdef moving rcu_end_inkernel_boot from rcupdate.h
rcu: Remove nohz_full full-system-idle state machine
rcu: Remove the RCU_KTHREAD_PRIO Kconfig option
rcu: Remove *_SLOW_* Kconfig options
srcu: Use rnp->lock wrappers to replace explicit memory barriers
rcu: Move rnp->lock wrappers for SRCU use
rcu: Convert rnp->lock wrappers to macros for SRCU use
rcu: Refactor #includes from include/linux/rcupdate.h
bcm47xx: Fix build regression
...
Usage of these apis and their compat versions makes
the syscalls: timer_settime and timer_gettime and their
compat implementations simpler.
This patch also serves as a preparatory patch for changing
syscalls to use new time_t data types to support the
y2038 effort by isolating the processing of user pointers
through these apis.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Usage of these apis and their compat versions makes
the syscalls: clock_nanosleep and nanosleep and
their compat implementations simpler.
This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Usage of these apis and their compat versions makes
the syscalls: clock_gettime, clock_settime, clock_getres
and their compat implementations simpler.
This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The timers cpu base lock could not be converted to a raw spinlock becaue
the lock held time was non-deterministic due to cascading and long lasting
timer wheel traversals.
The rework of the timer wheel to the new non-cascading model removed also
the wheel traversals and the lock held times are deterministic now. This
allows to make the lock raw and thereby unbreaks NOHz* on preempt-RT.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20170627161538.30257-1-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
These apis only need to be defined if CONFIG_COMPAT is
enabled.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
As we change the user space type for the timerfd and posix timer
functions to newer data types, we need some form of conversion
helpers to avoid duplicating that logic.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add helper functions to convert between struct timespec64 and
struct timespec at userspace boundaries.
This is a preparatory patch to use timespec64 as the basic type
internally in the kernel as timespec is not y2038 safe on 32 bit systems.
The patch helps the cause by containing all data conversions at the
userspace boundaries within these functions.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The idle load balancing registration path assumes that we only stop the
tick when the CPU is idle, ignoring the nohz full case. As a result, a
nohz full CPU that is running a task may be chosen to perform idle load
balancing.
Lets make sure that only CPUs in dynticks idle mode can be picked as
idle load balancers.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1497838322-10913-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The loadavg naming code still assumes that nohz == idle whereas its code
is actually handling well both nohz idle and nohz full.
So lets fix the naming according to what the code actually does, to
unconfuse the reader.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1497838322-10913-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge time(keeping) updates from John Stultz:
"Just a small set of changes, the biggest changes being the MONOTONIC_RAW
handling cleanup, and a new kselftest from Miroslav. Also a a clear
warning deprecating CONFIG_GENERIC_TIME_VSYSCALL_OLD, which affects ppc
and ia64."
CONFIG_GENERIC_TIME_VSYSCALL_OLD was introduced five years ago
to allow a transition from the old vsyscall implementations to
the new method (which simplified internal accounting and made
timekeeping more precise).
However, PPC and IA64 have yet to make the transition, despite
in some cases me sending test patches to try to help it along.
http://patches.linaro.org/patch/30501/http://patches.linaro.org/patch/35412/
If its helpful, my last pass at the patches can be found here:
https://git.linaro.org/people/john.stultz/linux.git dev/oldvsyscall-cleanup
So I think its time to set a deadline and make it clear this
is going away. So this patch adds warnings about this
functionality being dropped. Likely to be in v4.15.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Now that we fixed the sub-ns handling for CLOCK_MONOTONIC_RAW,
remove the duplicitive tk->raw_time.tv_nsec, which can be
stored in tk->tkr_raw.xtime_nsec (similarly to how its handled
for monotonic time).
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Mentz <danielmentz@google.com>
Tested-by: Daniel Mentz <danielmentz@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The expiry time of a posix cpu timer is supplied through sys_timer_set()
via a struct timespec. The timespec is validated for correctness.
In the actual set timer implementation the timespec is converted to a
scalar nanoseconds value. If the tv_sec part of the time spec is large
enough the conversion to nanoseconds (sec * NSEC_PER_SEC) overflows 64bit.
Mitigate that by using the timespec_to_ktime() conversion function, which
checks the tv_sec part for a potential mult overflow and clamps the result
to KTIME_MAX, which is about 292 years.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170620154113.588276707@linutronix.de
The expiry time of a itimer is supplied through sys_setitimer() via a
struct timeval. The timeval is validated for correctness.
In the actual set timer implementation the timeval is converted to a
scalar nanoseconds value. If the tv_sec part of the time spec is large
enough the conversion to nanoseconds (sec * NSEC_PER_SEC) overflows 64bit.
Mitigate that by using the timeval_to_ktime() conversion function, which
checks the tv_sec part for a potential mult overflow and clamps the result
to KTIME_MAX, which is about 292 years.
Reported-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170620154113.505981643@linutronix.de
Conflicts:
kernel/sched/Makefile
Pick up the waitqueue related renames - it didn't get much feedback,
so it appears to be uncontroversial. Famous last words? ;-)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Due to how the MONOTONIC_RAW accumulation logic was handled,
there is the potential for a 1ns discontinuity when we do
accumulations. This small discontinuity has for the most part
gone un-noticed, but since ARM64 enabled CLOCK_MONOTONIC_RAW
in their vDSO clock_gettime implementation, we've seen failures
with the inconsistency-check test in kselftest.
This patch addresses the issue by using the same sub-ns
accumulation handling that CLOCK_MONOTONIC uses, which avoids
the issue for in-kernel users.
Since the ARM64 vDSO implementation has its own clock_gettime
calculation logic, this patch reduces the frequency of errors,
but failures are still seen. The ARM64 vDSO will need to be
updated to include the sub-nanosecond xtime_nsec values in its
calculation for this issue to be completely fixed.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: "stable #4 . 8+" <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In tests, which excercise switching of clocksources, a NULL
pointer dereference can be observed on AMR64 platforms in the
clocksource read() function:
u64 clocksource_mmio_readl_down(struct clocksource *c)
{
return ~(u64)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
}
This is called from the core timekeeping code via:
cycle_now = tkr->read(tkr->clock);
tkr->read is the cached tkr->clock->read() function pointer.
When the clocksource is changed then tkr->clock and tkr->read
are updated sequentially. The code above results in a sequential
load operation of tkr->read and tkr->clock as well.
If the store to tkr->clock hits between the loads of tkr->read
and tkr->clock, then the old read() function is called with the
new clock pointer. As a consequence the read() function
dereferences a different data structure and the resulting 'reg'
pointer can point anywhere including NULL.
This problem was introduced when the timekeeping code was
switched over to use struct tk_read_base. Before that, it was
theoretically possible as well when the compiler decided to
reload clock in the code sequence:
now = tk->clock->read(tk->clock);
Add a helper function which avoids the issue by reading
tk_read_base->clock once into a local variable clk and then issue
the read function via clk->read(clk). This guarantees that the
read() function always gets the proper clocksource pointer handed
in.
Since there is now no use for the tkr.read pointer, this patch
also removes it, and to address stopping the fast timekeeper
during suspend/resume, it introduces a dummy clocksource to use
rather then just a dummy read function.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: stable <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Daniel Mentz <danielmentz@google.com>
Link: http://lkml.kernel.org/r/1496965462-20003-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No nanosleep implementation modifies the rqtp argument. Mark is const.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
No point in converting the expiry time back and forth.
No point either to update the value in the caller supplied variable. mark
the rqtp argument const.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Move them to the native implementations and get rid of the set_fs() hackery.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-13-viro@ZenIV.linux.org.uk
get rid of set_fs(), sanitize compat copyin/copyout.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-12-viro@ZenIV.linux.org.uk
... and get rid of set_fs() in there
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-11-viro@ZenIV.linux.org.uk
... and get rid of set_fs() in there
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-10-viro@ZenIV.linux.org.uk
Get rid of set_fs() mess and sanitize compat_{get,put}_timex(),
while we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-9-viro@ZenIV.linux.org.uk
Frederic Weisbecker