Extend the support for LZ4 compression to be used with hibernation.
The main idea is that different compression algorithms
have different characteristics and hibernation may benefit when it uses
any of these algorithms: a default algorithm, having higher
compression rate but is slower(compression/decompression) and a
secondary algorithm, that is faster(compression/decompression) but has
lower compression rate.
LZ4 algorithm has better decompression speeds over LZO. This reduces
the hibernation image restore time.
As per test results:
LZO LZ4
Size before Compression(bytes) 682696704 682393600
Size after Compression(bytes) 146502402 155993547
Decompression Rate 335.02 MB/s 501.05 MB/s
Restore time 4.4s 3.8s
LZO is the default compression algorithm used for hibernation. Enable
CONFIG_HIBERNATION_COMP_LZ4 to set the default compressor as LZ4.
Signed-off-by: Nikhil V <quic_nprakash@quicinc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently for hibernation, LZO is the only compression algorithm
available and uses the existing LZO library calls. However, there
is no flexibility to switch to other algorithms which provides better
results. The main idea is that different compression algorithms have
different characteristics and hibernation may benefit when it uses
alternate algorithms.
By moving to crypto based APIs, it lays a foundation to use other
compression algorithms for hibernation. There are no functional changes
introduced by this approach.
Signed-off-by: Nikhil V <quic_nprakash@quicinc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it. Therefore, remove the "select SRCU"
Kconfig statements.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Run the following command to find and remove the trailing spaces and tabs:
$ find kernel/power/ -type f | xargs sed -r -i 's/[ \t]+$//'
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove "default n" options. If the "default" line is removed, it
defaults to 'n'.
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Energy Model supports now other devices like GPUs, DSPs, not only CPUs.
Thus, update the description in the config option. Remove also unneeded
"default n". If the "default" line is removed, it defaults to 'n'.
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Make it possible to reduce the attack surface in case the snapshot
device is not to be used from userspace.
Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ARCH_SAVE_PAGE_KEYS has been introduced in order to be able to save
and restore s390 specific storage keys into a hibernation image.
With hibernation support removed from s390 there is no point in
keeping the callbacks.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The sysfs attribute `/sys/power/sync_on_suspend` controls, whether or not
filesystems are synced by the kernel before system suspend.
Congruously, the behaviour of build-time switch CONFIG_SUSPEND_SKIP_SYNC
is slightly changed: It now defines the run-tim default for the new sysfs
attribute `/sys/power/sync_on_suspend`.
The run-time attribute is added because the existing corresponding
build-time Kconfig flag for (`CONFIG_SUSPEND_SKIP_SYNC`) is not flexible
enough. E.g. Linux distributions that provide pre-compiled kernels
usually want to stick with the default (sync filesystems before suspend)
but under special conditions this needs to be changed.
One example for such a special condition is user-space handling of
suspending block devices (e.g. using `cryptsetup luksSuspend` or `dmsetup
suspend`) before system suspend. The Kernel trying to sync filesystems
after the underlying block device already got suspended obviously leads
to dead-locks. Be aware that you have to take care of the filesystem sync
yourself before suspending the system in those scenarios.
Signed-off-by: Jonas Meurer <jonas@freesources.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Convert the PM documents to ReST, in order to allow them to
build with Sphinx.
The conversion is actually:
- add blank lines and indentation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch provides an arch option, ARCH_SUSPEND_NONZERO_CPU, to
opt-in to allowing suspend to occur on one of the housekeeping CPUs
rather than hardcoded CPU0.
This will allow CPU0 to be a nohz_full CPU with a later change.
It may be possible for platforms with hardware/firmware restrictions
on suspend/wake effectively support this by handing off the final
stage to CPU0 when kernel housekeeping is no longer required. Another
option is to make housekeeping / nohz_full mask dynamic at runtime,
but the complexity could not be justified at this time.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lkml.kernel.org/r/20190411033448.20842-4-npiggin@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Several subsystems in the kernel (task scheduler and/or thermal at the
time of writing) can benefit from knowing about the energy consumed by
CPUs. Yet, this information can come from different sources (DT or
firmware for example), in different formats, hence making it hard to
exploit without a standard API.
As an attempt to address this, introduce a centralized Energy Model
(EM) management framework which aggregates the power values provided
by drivers into a table for each performance domain in the system. The
power cost tables are made available to interested clients (e.g. task
scheduler or thermal) via platform-agnostic APIs. The overall design
is represented by the diagram below (focused on Arm-related drivers as
an example, but applicable to any architecture):
+---------------+ +-----------------+ +-------------+
| Thermal (IPA) | | Scheduler (EAS) | | Other |
+---------------+ +-----------------+ +-------------+
| | em_pd_energy() |
| | em_cpu_get() |
+-----------+ | +--------+
| | |
v v v
+---------------------+
| |
| Energy Model |
| |
| Framework |
| |
+---------------------+
^ ^ ^
| | | em_register_perf_domain()
+----------+ | +---------+
| | |
+---------------+ +---------------+ +--------------+
| cpufreq-dt | | arm_scmi | | Other |
+---------------+ +---------------+ +--------------+
^ ^ ^
| | |
+--------------+ +---------------+ +--------------+
| Device Tree | | Firmware | | ? |
+--------------+ +---------------+ +--------------+
Drivers (typically, but not limited to, CPUFreq drivers) can register
data in the EM framework using the em_register_perf_domain() API. The
calling driver must provide a callback function with a standardized
signature that will be used by the EM framework to build the power
cost tables of the performance domain. This design should offer a lot of
flexibility to calling drivers which are free of reading information
from any location and to use any technique to compute power costs.
Moreover, the capacity states registered by drivers in the EM framework
are not required to match real performance states of the target. This
is particularly important on targets where the performance states are
not known by the OS.
The power cost coefficients managed by the EM framework are specified in
milli-watts. Although the two potential users of those coefficients (IPA
and EAS) only need relative correctness, IPA specifically needs to
compare the power of CPUs with the power of other components (GPUs, for
example), which are still expressed in absolute terms in their
respective subsystems. Hence, specifying the power of CPUs in
milli-watts should help transitioning IPA to using the EM framework
without introducing new problems by keeping units comparable across
sub-systems.
On the longer term, the EM of other devices than CPUs could also be
managed by the EM framework, which would enable to remove the absolute
unit. However, this is not absolutely required as a first step, so this
extension of the EM framework is left for later.
On the client side, the EM framework offers APIs to access the power
cost tables of a CPU (em_cpu_get()), and to estimate the energy
consumed by the CPUs of a performance domain (em_pd_energy()). Clients
such as the task scheduler can then use these APIs to access the shared
data structures holding the Energy Model of CPUs.
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: adharmap@codeaurora.org
Cc: chris.redpath@arm.com
Cc: currojerez@riseup.net
Cc: dietmar.eggemann@arm.com
Cc: edubezval@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: javi.merino@kernel.org
Cc: joel@joelfernandes.org
Cc: juri.lelli@redhat.com
Cc: morten.rasmussen@arm.com
Cc: patrick.bellasi@arm.com
Cc: pkondeti@codeaurora.org
Cc: skannan@codeaurora.org
Cc: smuckle@google.com
Cc: srinivas.pandruvada@linux.intel.com
Cc: thara.gopinath@linaro.org
Cc: tkjos@google.com
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Cc: viresh.kumar@linaro.org
Link: https://lkml.kernel.org/r/20181203095628.11858-4-quentin.perret@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit ea0212f40c (power: auto select CONFIG_SRCU) made the code in
drivers/base/power/wakeup.c use SRCU instead of RCU, but it forgot to
select CONFIG_SRCU in Kconfig, which leads to the following build
error if CONFIG_SRCU is not selected somewhere else:
drivers/built-in.o: In function `wakeup_source_remove':
(.text+0x3c6fc): undefined reference to `synchronize_srcu'
drivers/built-in.o: In function `pm_print_active_wakeup_sources':
(.text+0x3c7a8): undefined reference to `__srcu_read_lock'
drivers/built-in.o: In function `pm_print_active_wakeup_sources':
(.text+0x3c84c): undefined reference to `__srcu_read_unlock'
drivers/built-in.o: In function `device_wakeup_arm_wake_irqs':
(.text+0x3d1d8): undefined reference to `__srcu_read_lock'
drivers/built-in.o: In function `device_wakeup_arm_wake_irqs':
(.text+0x3d228): undefined reference to `__srcu_read_unlock'
drivers/built-in.o: In function `device_wakeup_disarm_wake_irqs':
(.text+0x3d24c): undefined reference to `__srcu_read_lock'
drivers/built-in.o: In function `device_wakeup_disarm_wake_irqs':
(.text+0x3d29c): undefined reference to `__srcu_read_unlock'
drivers/built-in.o:(.data+0x4158): undefined reference to `process_srcu'
Fix this error by selecting CONFIG_SRCU when PM_SLEEP is enabled.
Fixes: ea0212f40c (power: auto select CONFIG_SRCU)
Cc: 4.2+ <stable@vger.kernel.org> # 4.2+
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
[ rjw: Minor subject/changelog fixups ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The drivers/base/power/ directory is special and contains code related
to power management core like system suspend/resume, hibernation, etc.
It was fine to keep the OPP code inside it when we had just one file for
it, but it is growing now and already has a directory for itself.
Lets move it directly under drivers/ directory, just like cpufreq and
cpuidle.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The APM emulation code does multiple things, and some of them depend on
PM_SLEEP, while the battery management does not. However, selecting
the symbol like SHARPSL_PM does causes a Kconfig warning:
warning: (SHARPSL_PM && PMAC_APM_EMU) selects APM_EMULATION which has unmet direct dependencies (PM && SYS_SUPPORTS_APM_EMULATION)
From all I can tell, this is completely harmless, and we can simply allow
APM_EMULATION to be enabled here, even if PM is not.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The Linux kernel suspend path has traditionally invoked sys_sync()
before freezing user threads.
But sys_sync() can be expensive, and some user-space OS's do not want
the kernel to pay the cost of sys_sync() on every suspend -- preferring
invoke sync() from user-space if/when they want it.
So make sys_sync on suspend build-time optional.
The default is unchanged.
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Many harddisks (mostly WD ones) have firmware problems and take too
long, more than 10 seconds, to resume from suspend. And this often
exceeds the default DPM watchdog timeout (12 seconds), resulting in a
kernel panic out of sudden.
Since most distros just take the default as is, we should give a bit
more safer value. This patch increases the default value from 12
seconds to one minute, which has been confirmed to be long enough for
such problematic disks.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=91921
Fixes: 70fea60d88 (PM / Sleep: Detect device suspend/resume lockup and log event)
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
SRCU is not necessary to be compiled by default in all cases. For tinification
efforts not compiling SRCU unless necessary is desirable.
The current patch tries to make compiling SRCU optional by introducing a new
Kconfig option CONFIG_SRCU which is selected when any of the components making
use of SRCU are selected.
If we do not select CONFIG_SRCU, srcu.o will not be compiled at all.
text data bss dec hex filename
2007 0 0 2007 7d7 kernel/rcu/srcu.o
Size of arch/powerpc/boot/zImage changes from
text data bss dec hex filename
831552 64180 23944 919676 e087c arch/powerpc/boot/zImage : before
829504 64180 23952 917636 e0084 arch/powerpc/boot/zImage : after
so the savings are about ~2000 bytes.
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ]
Having switched over all of the users of CONFIG_PM_RUNTIME to use
CONFIG_PM directly, turn the latter into a user-selectable option
and drop the former entirely from the tree.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
