16 Jul, 2016
1 commit
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On Intel hardware, native_play_dead() uses mwait_play_dead() by
default and only falls back to the other methods if that fails.
That also happens during resume from hibernation, when the restore
(boot) kernel runs disable_nonboot_cpus() to take all of the CPUs
except for the boot one offline.However, that is problematic, because the address passed to
__monitor() in mwait_play_dead() is likely to be written to in the
last phase of hibernate image restoration and that causes the "dead"
CPU to start executing instructions again. Unfortunately, the page
containing the address in that CPU's instruction pointer may not be
valid any more at that point.First, that page may have been overwritten with image kernel memory
contents already, so the instructions the CPU attempts to execute may
simply be invalid. Second, the page tables previously used by that
CPU may have been overwritten by image kernel memory contents, so the
address in its instruction pointer is impossible to resolve then.A report from Varun Koyyalagunta and investigation carried out by
Chen Yu show that the latter sometimes happens in practice.To prevent it from happening, temporarily change the smp_ops.play_dead
pointer during resume from hibernation so that it points to a special
"play dead" routine which uses hlt_play_dead() and avoids the
inadvertent "revivals" of "dead" CPUs this way.A slightly unpleasant consequence of this change is that if the
system is hibernated with one or more CPUs offline, it will generally
draw more power after resume than it did before hibernation, because
the physical state entered by CPUs via hlt_play_dead() is higher-power
than the mwait_play_dead() one in the majority of cases. It is
possible to work around this, but it is unclear how much of a problem
that's going to be in practice, so the workaround will be implemented
later if it turns out to be necessary.Link: https://bugzilla.kernel.org/show_bug.cgi?id=106371
Reported-by: Varun Koyyalagunta
Original-by: Chen Yu
Tested-by: Chen Yu
Signed-off-by: Rafael J. Wysocki
Acked-by: Ingo Molnar
10 Jul, 2016
1 commit
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Make it possible to protect all pages holding image data during
hibernate image restoration by setting them read-only (so as to
catch attempts to write to those pages after image data have been
stored in them).This adds overhead to image restoration code (it may cause large
page mappings to be split as a result of page flags changes) and
the errors it protects against should never happen in theory, so
the feature is only active after passing hibernate=protect_image
to the command line of the restore kernel.Also it only is built if CONFIG_DEBUG_RODATA is set.
Signed-off-by: Rafael J. Wysocki
28 Jun, 2016
1 commit
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This makes pm notifier PREPARE/POST symmetrical: if PREPARE
fails, we will only undo what ever happened on PREPARE.It fixes the unbalanced CPU hotplug enable in CPU PM notifier.
Signed-off-by: Lianwei Wang
Signed-off-by: Rafael J. Wysocki
05 Jan, 2016
1 commit
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Some sysfs attributes in /sys/power/ should really be read-only,
so add support for that, convert those attributes to read-only
and drop the stub .show() routines from them.Original-by: Sergey Senozhatsky
Signed-off-by: Rafael J. Wysocki
19 May, 2015
1 commit
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Stop abusing struct page functionality and the swap end_io handler, and
instead add a modified version of the blk-lib.c bio_batch helpers.Also move the block I/O code into swap.c as they are directly tied into
each other.Signed-off-by: Christoph Hellwig
Tested-by: Pavel Machek
Tested-by: Ming Lin
Acked-by: Pavel Machek
Acked-by: Rafael J. Wysocki
Signed-off-by: Jens Axboe
03 Nov, 2014
1 commit
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This patch migrates swsusp_show_speed and its callers to using ktime_t instead
of 'struct timeval' which suffers from the y2038 problem.Changes to swsusp_show_speed:
- use ktime_t for start and stop times
- pass start and stop times by value
Calling functions affected:
- load_image
- load_image_lzo
- save_image
- save_image_lzo
- hibernate_preallocate_memory
Design decisions:
- use ktime_t to preserve same granularity of reporting as before
- use centisecs logic as before to avoid 'div by zero' issues caused by
using seconds and nanoseconds directly
- use monotonic time (ktime_get()) since we only care about elapsed time.Signed-off-by: Tina Ruchandani
Suggested-by: Arnd Bergmann
Reviewed-by: Arnd Bergmann
Acked-by: Pavel Machek
Signed-off-by: Rafael J. Wysocki
03 Sep, 2014
1 commit
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After commit d431cbc53cb7 (PM / sleep: Simplify sleep states sysfs
interface code) the pm_states[] array is not populated initially,
which causes setup_test_suspend() to always fail and the suspend
testing during boot doesn't work any more.Fix the problem by using pm_labels[] instead of pm_states[] in
setup_test_suspend() and storing a pointer to the label of the
sleep state to test rather than the number representing it,
because the connection between the state numbers and labels is
only established by suspend_set_ops().Fixes: d431cbc53cb7 (PM / sleep: Simplify sleep states sysfs interface code)
Reported-by: Srinivas Pandruvada
Signed-off-by: Rafael J. Wysocki
21 Jul, 2014
1 commit
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Simplify the sleep states sysfs interface /sys/power/state code by
redefining pm_states[] as an array of pointers to constant strings
such that only the entries corresponding to valid states are set.Signed-off-by: Rafael J. Wysocki
26 May, 2014
2 commits
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Use the observation that, for platform-dependent sleep states
(PM_SUSPEND_STANDBY, PM_SUSPEND_MEM), a given state is either
always supported or always unsupported and store that information
in pm_states[] instead of calling valid_state() every time we
need to check it.Also do not use valid_state() for PM_SUSPEND_FREEZE, which is always
valid, and move the pm_test_level validity check for PM_SUSPEND_FREEZE
directly into enter_state().Signed-off-by: Rafael J. Wysocki
-
To allow sleep states corresponding to the "mem", "standby" and
"freeze" lables to be different from the pm_states[] indexes of
those strings, introduce struct pm_sleep_state, consisting of
a string label and a state number, and turn pm_states[] into an
array of objects of that type.This modification should not lead to any functional changes.
Signed-off-by: Rafael J. Wysocki
08 Apr, 2014
1 commit
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To increase compiler portability there is which
provides convenience macros for various gcc constructs. Eg: __weak for
__attribute__((weak)). I've replaced all instances of gcc attributes
with the right macro in the kernel subsystem.Signed-off-by: Gideon Israel Dsouza
Cc: "Rafael J. Wysocki"
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 Mar, 2014
1 commit
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Move prototype declaration of function to header file
kernel/power/power.h because it is used by more than one file.This eliminates the following warning in kernel/power/snapshot.c:
kernel/power/snapshot.c:1588:16: warning: no previous prototype for ‘swsusp_save’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria
Reviewed-by: Josh Triplett
Acked-by: Pavel Machek
Signed-off-by: Rafael J. Wysocki
01 Jul, 2012
1 commit
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It is often useful to suspend to memory after hibernation image has been
written to disk. If the battery runs out or power is otherwise lost, the
computer will resume from the hibernated image. If not, it will resume
from memory and hibernation image will be discarded.Signed-off-by: Bojan Smojver
Signed-off-by: Rafael J. Wysocki
02 May, 2012
2 commits
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Android allows user space to manipulate wakelocks using two
sysfs file located in /sys/power/, wake_lock and wake_unlock.
Writing a wakelock name and optionally a timeout to the wake_lock
file causes the wakelock whose name was written to be acquired (it
is created before is necessary), optionally with the given timeout.
Writing the name of a wakelock to wake_unlock causes that wakelock
to be released.Implement an analogous interface for user space using wakeup sources.
Add the /sys/power/wake_lock and /sys/power/wake_unlock files
allowing user space to create, activate and deactivate wakeup
sources, such that writing a name and optionally a timeout to
wake_lock causes the wakeup source of that name to be activated,
optionally with the given timeout. If that wakeup source doesn't
exist, it will be created and then activated. Writing a name to
wake_unlock causes the wakeup source of that name, if there is one,
to be deactivated. Wakeup sources created with the help of
wake_lock that haven't been used for more than 5 minutes are garbage
collected and destroyed. Moreover, there can be only WL_NUMBER_LIMIT
wakeup sources created with the help of wake_lock present at a time.The data type used to track wakeup sources created by user space is
called "struct wakelock" to indicate the origins of this feature.This version of the patch includes an rbtree manipulation fix from John Stultz.
Signed-off-by: Rafael J. Wysocki
Acked-by: Greg Kroah-Hartman
Reviewed-by: NeilBrown -
Introduce a mechanism by which the kernel can trigger global
transitions to a sleep state chosen by user space if there are no
active wakeup sources.It consists of a new sysfs attribute, /sys/power/autosleep, that
can be written one of the strings returned by reads from
/sys/power/state, an ordered workqueue and a work item carrying out
the "suspend" operations. If a string representing the system's
sleep state is written to /sys/power/autosleep, the work item
triggering transitions to that state is queued up and it requeues
itself after every execution until user space writes "off" to
/sys/power/autosleep.That work item enables the detection of wakeup events using the
functions already defined in drivers/base/power/wakeup.c (with one
small modification) and calls either pm_suspend(), or hibernate() to
put the system into a sleep state. If a wakeup event is reported
while the transition is in progress, it will abort the transition and
the "system suspend" work item will be queued up again.Signed-off-by: Rafael J. Wysocki
Acked-by: Greg Kroah-Hartman
Reviewed-by: NeilBrown
18 Feb, 2012
1 commit
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The enter_state() function in kernel/power/suspend.c should be
static and state_store() in kernel/power/suspend.c should call
pm_suspend() instead of it, so make that happen (which also reduces
code duplication related to suspend statistics).Signed-off-by: Rafael J. Wysocki
Acked-by: Srivatsa S. Bhat
13 Feb, 2012
1 commit
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The Finish label in suspend_freeze_processes() is in fact unnecessary
and makes the function look more complicated than it really is, so
remove that label (along with a few empty lines).Signed-off-by: Rafael J. Wysocki
Acked-by: Srivatsa S. Bhat
05 Feb, 2012
1 commit
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If freezing of kernel threads fails, we are expected to automatically
thaw tasks in the error recovery path. However, at times, we encounter
situations in which we would like the automatic error recovery path
to thaw only the kernel threads, because we want to be able to do
some more cleanup before we thaw userspace. Something like:error = freeze_kernel_threads();
if (error) {
/* Do some cleanup *//* Only then thaw userspace tasks*/
thaw_processes();
}An example of such a situation is where we freeze/thaw filesystems
during suspend/hibernation. There, if freezing of kernel threads
fails, we would like to thaw the frozen filesystems before thawing
the userspace tasks.So, modify freeze_kernel_threads() to thaw only kernel threads in
case of freezing failure. And change suspend_freeze_processes()
accordingly. (At the same time, let us also get rid of the rather
cryptic usage of the conditional operator (:?) in that function.)[rjw: In fact, this patch fixes a regression introduced during the
3.3 merge window, because without it thaw_processes() may be called
before swsusp_free() in some situations and that may lead to massive
memory allocation failures.]Signed-off-by: Srivatsa S. Bhat
Acked-by: Tejun Heo
Acked-by: Nigel Cunningham
Signed-off-by: Rafael J. Wysocki
07 Dec, 2011
1 commit
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Commit 2aede851ddf08666f68ffc17be446420e9d2a056 (PM / Hibernate: Freeze
kernel threads after preallocating memory) moved the freezing of kernel
threads to hibernation_snapshot() function.So now, if the call to hibernation_snapshot() returns early due to a
successful hibernation test, the caller has to thaw processes to ensure
that the system gets back to its original state.But in SNAPSHOT_CREATE_IMAGE hibernation ioctl, the caller does not thaw
processes in case hibernation_snapshot() returned due to a successful
freezer test. Fix this issue. But note we still send the value of 'in_suspend'
(which is now 0) to userspace, because we are not in an error path per-se,
and moreover, the value of in_suspend correctly depicts the situation here.Signed-off-by: Srivatsa S. Bhat
Signed-off-by: Rafael J. Wysocki
17 Oct, 2011
2 commits
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Use threads for LZO compression/decompression on hibernate/thaw.
Improve buffering on hibernate/thaw.
Calculate/verify CRC32 of the image pages on hibernate/thaw.In my testing, this improved write/read speed by a factor of about two.
Signed-off-by: Bojan Smojver
Signed-off-by: Rafael J. Wysocki -
There is a problem with the current ordering of hibernate code which
leads to deadlocks in some filesystems' memory shrinkers. Namely,
some filesystems use freezable kernel threads that are inactive when
the hibernate memory preallocation is carried out. Those same
filesystems use memory shrinkers that may be triggered by the
hibernate memory preallocation. If those memory shrinkers wait for
the frozen kernel threads, the hibernate process deadlocks (this
happens with XFS, for one example).Apparently, it is not technically viable to redesign the filesystems
in question to avoid the situation described above, so the only
possible solution of this issue is to defer the freezing of kernel
threads until the hibernate memory preallocation is done, which is
implemented by this change.Unfortunately, this requires the memory preallocation to be done
before the "prepare" stage of device freeze, so after this change the
only way drivers can allocate additional memory for their freeze
routines in a clean way is to use PM notifiers.Reported-by: Christoph
Signed-off-by: Rafael J. Wysocki
18 May, 2011
1 commit
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Martin reports that on his system hibernation occasionally fails due
to the lack of memory, because the radeon driver apparently allocates
too much of it during the device freeze stage. It turns out that the
amount of memory allocated by radeon during hibernation (and
presumably during system suspend too) depends on the utilization of
the GPU (e.g. hibernating while there are two KDE 4 sessions with
compositing enabled causes radeon to allocate more memory than for
one KDE 4 session).In principle it should be possible to use image_size to make the
memory preallocation mechanism free enough memory for the radeon
driver, but in practice it is not easy to guess the right value
because of the way the preallocation code uses image_size. For this
reason, it seems reasonable to allow users to control the amount of
memory reserved for driver allocations made after the hibernate
preallocation, which currently is constant and amounts to 1 MB.Introduce a new sysfs file, /sys/power/reserved_size, whose value
will be used as the amount of memory to reserve for the
post-preallocation reservations made by device drivers, in bytes.
For backwards compatibility, set its default (and initial) value to
the currently used number (1 MB).References: https://bugzilla.kernel.org/show_bug.cgi?id=34102
Reported-and-tested-by: Martin Steigerwald
Signed-off-by: Rafael J. Wysocki
17 Oct, 2010
2 commits
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The default hibernation image size is currently hard coded and euqal
to 500 MB, which is not a reasonable default on many contemporary
systems. Make it equal 2/5 of the total RAM size (this is slightly
below the maximum, i.e. 1/2 of the total RAM size, and seems to be
generally suitable).Signed-off-by: Rafael J. Wysocki
Tested-by: M. Vefa Bicakci -
Compress hibernation image with LZO in order to save on I/O and
therefore time to hibernate/thaw.[rjw: Added hibernate=nocompress command line option instead of just
nocompress which would be confusing, fixed a couple of compiler
warnings, fixed kerneldoc comments, minor cleanups.]Signed-off-by: Bojan Smojver
Signed-off-by: Rafael J. Wysocki
11 May, 2010
2 commits
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Move block I/O operations to a separate file. It is because it will
be used later not only by the swap writer.Signed-off-by: Jiri Slaby
Signed-off-by: Rafael J. Wysocki -
Remove support of reads with offset. This means snapshot_read/write_next
now does not accept count parameter. It allows to clean up the functions
and snapshot handle which no longer needs to care about offsets./dev/snapshot handler is converted to simple_{read_from,write_to}_buffer
which take care of offsets.Signed-off-by: Jiri Slaby
Acked-by: Pavel Machek
Signed-off-by: Rafael J. Wysocki
15 Sep, 2009
1 commit
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Since the hibernation code is now going to use allocations of memory
to make enough room for the image, it can also use the page frames
allocated at this stage as image page frames. The low-level
hibernation code needs to be rearranged for this purpose, but it
allows us to avoid freeing a great number of pages and allocating
these same pages once again later, so it generally is worth doing.[rev. 2: Take highmem into account correctly.]
Signed-off-by: Rafael J. Wysocki
13 Jun, 2009
3 commits
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Change the name of kernel/power/disk.c to kernel/power/hibernate.c
in analogy with the file names introduced by the changes that
separated the suspend to RAM and standby funtionality from the
common PM functions.Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek -
Move the suspend to RAM and standby code from kernel/power/main.c
to two separate files, kernel/power/suspend.c containing the basic
functions and kernel/power/suspend_test.c containing the automatic
suspend test facility based on the RTC clock alarm.There are no changes in functionality related to these modifications.
Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek -
A future patch is going to modify the memory shrinking code so that
it will make memory allocations to free memory instead of using an
artificial memory shrinking mechanism for that. For this purpose it
is convenient to move swsusp_shrink_memory() from
kernel/power/swsusp.c to kernel/power/snapshot.c, because the new
memory-shrinking code is going to use things that are local to
kernel/power/snapshot.c .[rev. 2: Make some functions static and remove their headers from
kernel/power/power.h]Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek
Acked-by: Wu Fengguang
21 Oct, 2008
1 commit
-
Signed-off-by: Al Viro
27 Jul, 2008
1 commit
-
This patch implements devices state save/restore before after kexec.
This patch together with features in kexec_jump patch can be used for
following:- A simple hibernation implementation without ACPI support. You can kexec a
hibernating kernel, save the memory image of original system and shutdown
the system. When resuming, you restore the memory image of original system
via ordinary kexec load then jump back.- Kernel/system debug through making system snapshot. You can make system
snapshot, jump back, do some thing and make another system snapshot.- Cooperative multi-kernel/system. With kexec jump, you can switch between
several kernels/systems quickly without boot process except the first time.
This appears like swap a whole kernel/system out/in.- A general method to call program in physical mode (paging turning
off). This can be used to invoke BIOS code under Linux.The following user-space tools can be used with kexec jump:
- kexec-tools needs to be patched to support kexec jump. The patches
and the precompiled kexec can be download from the following URL:
source: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-src_git_kh10.tar.bz2
patches: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-patches_git_kh10.tar.bz2
binary: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec_git_kh10- makedumpfile with patches are used as memory image saving tool, it
can exclude free pages from original kernel memory image file. The
patches and the precompiled makedumpfile can be download from the
following URL:
source: http://khibernation.sourceforge.net/download/release_v10/makedumpfile/makedumpfile-src_cvs_kh10.tar.bz2
patches: http://khibernation.sourceforge.net/download/release_v10/makedumpfile/makedumpfile-patches_cvs_kh10.tar.bz2
binary: http://khibernation.sourceforge.net/download/release_v10/makedumpfile/makedumpfile_cvs_kh10- An initramfs image can be used as the root file system of kexeced
kernel. An initramfs image built with "BuildRoot" can be downloaded
from the following URL:
initramfs image: http://khibernation.sourceforge.net/download/release_v10/initramfs/rootfs_cvs_kh10.gz
All user space tools above are included in the initramfs image.Usage example of simple hibernation:
1. Compile and install patched kernel with following options selected:
CONFIG_X86_32=y
CONFIG_RELOCATABLE=y
CONFIG_KEXEC=y
CONFIG_CRASH_DUMP=y
CONFIG_PM=y
CONFIG_HIBERNATION=y
CONFIG_KEXEC_JUMP=y2. Build an initramfs image contains kexec-tool and makedumpfile, or
download the pre-built initramfs image, called rootfs.gz in
following text.3. Prepare a partition to save memory image of original kernel, called
hibernating partition in following text.4. Boot kernel compiled in step 1 (kernel A).
5. In the kernel A, load kernel compiled in step 1 (kernel B) with
/sbin/kexec. The shell command line can be as follow:/sbin/kexec --load-preserve-context /boot/bzImage --mem-min=0x100000
--mem-max=0xffffff --initrd=rootfs.gz6. Boot the kernel B with following shell command line:
/sbin/kexec -e
7. The kernel B will boot as normal kexec. In kernel B the memory
image of kernel A can be saved into hibernating partition as
follow:jump_back_entry=`cat /proc/cmdline | tr ' ' '\n' | grep kexec_jump_back_entry | cut -d '='`
echo $jump_back_entry > kexec_jump_back_entry
cp /proc/vmcore dump.elfThen you can shutdown the machine as normal.
8. Boot kernel compiled in step 1 (kernel C). Use the rootfs.gz as
root file system.9. In kernel C, load the memory image of kernel A as follow:
/sbin/kexec -l --args-none --entry=`cat kexec_jump_back_entry` dump.elf
10. Jump back to the kernel A as follow:
/sbin/kexec -e
Then, kernel A is resumed.
Implementation point:
To support jumping between two kernels, before jumping to (executing)
the new kernel and jumping back to the original kernel, the devices
are put into quiescent state, and the state of devices and CPU is
saved. After jumping back from kexeced kernel and jumping to the new
kernel, the state of devices and CPU are restored accordingly. The
devices/CPU state save/restore code of software suspend is called to
implement corresponding function.Known issues:
- Because the segment number supported by sys_kexec_load is limited,
hibernation image with many segments may not be load. This is
planned to be eliminated by adding a new flag to sys_kexec_load to
make a image can be loaded with multiple sys_kexec_load invoking.Now, only the i386 architecture is supported.
Signed-off-by: Huang Ying
Acked-by: Vivek Goyal
Cc: "Eric W. Biederman"
Cc: Pavel Machek
Cc: Nigel Cunningham
Cc: "Rafael J. Wysocki"
Cc: Ingo Molnar
Cc: Thomas Gleixner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
02 Feb, 2008
8 commits
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This patch makes the freezer optional for suspend to allow the
system to work (or not work) like the original PMU suspend.Signed-off-by: Johannes Berg
Acked-by: Pavel Machek
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Len Brown -
Move the low level restore code to kernel/power/disk.c , since the
corresponding low level hibernation code is already there.Make restore fail if device_power_down(PMSG_PRETHAW) returns an
error.Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek
Signed-off-by: Len Brown -
This patch (as1008b) converts the PM notifier routines from inline
calls to out-of-line code. It also prevents pm_chain_head from
being created when CONFIG_PM_SLEEP isn't enabled, and EXPORTs the
notifier registration and unregistration routines.Signed-off-by: Alan Stern
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Len Brown -
Make it possible to test the hibernation core code with the help of the
/sys/power/pm_test attribute introduced for suspend testing in the previous
patch.Writing an appropriate string to this file causes the hibernation code to work
in one of the test modes defined as follows:freezer
- test the freezing of processesdevices
- test the freezing of processes and suspending of devicesplatform
- test the freezing of processes, suspending of devices and platform global
control methods(*)processors
- test the freezing of processes, suspending of devices, platform global
control methods(*) and the disabling of nonboot CPUscore
- test the freezing of processes, suspending of devices, platform global
control methods(*), the disabling of nonboot CPUs and suspending of
platform/system devices(*) - the platform global control methods are only available on ACPI systems
and are only tested if the hibernation mode is set to "platform"Then, if a hibernation is started by normal means, the hibernation core will
perform its normal operations up to the point indicated by given test level.
Next, it will wait for 5 seconds and carry out the resume operations needed to
transition the system back to the fully functional state.Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek
Signed-off-by: Len Brown -
Introduce sysfs attribute /sys/power/pm_test allowing one to test the suspend
core code. Namely, writing one of the strings:freezer
devices
platform
processors
coreto this file causes the suspend code to work in one of the test modes defined as
follows:freezer
- test the freezing of processesdevices
- test the freezing of processes and suspending of devicesplatform
- test the freezing of processes, suspending of devices and platform global
control methods(*)processors
- test the freezing of processes, suspending of devices, platform global
control methods and the disabling of nonboot CPUscore
- test the freezing of processes, suspending of devices, platform global
control methods, the disabling of nonboot CPUs and suspending of
platform/system devices(*) These are ACPI global control methods on ACPI systems
Then, if a suspend is started by normal means, the suspend core will perform
its normal operations up to the point indicated by given test level. Next, it
will wait for 5 seconds and carry out the resume operations needed to transition
the system back to the fully functional state.Writing "none" to /sys/power/pm_test turns the testing off.
When open for reading, /sys/power/pm_test contains a space-separated list of all
available tests (including "none" that represents the normal functionality) in
which the current test level is indicated by square brackets.Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek
Signed-off-by: Len Brown -
This patch moves the prototypes of count_highmem_pages() and
restore_highmem() to kernel/power/power.hSigned-off-by: Adrian Bunk
Acked-by: Pavel Machek
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Len Brown -
Move the definitions of hibernation ioctls to a separate header file in
include/linux, which can be exported to the user space.Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek
Signed-off-by: Len Brown -
Three ioctl numbers belonging to the hibernation userland interface,
SNAPSHOT_ATOMIC_SNAPSHOT, SNAPSHOT_AVAIL_SWAP, SNAPSHOT_GET_SWAP_PAGE,
are defined in a wrong way (eg. not portable). Provide new ioctl numbers for
these ioctls and mark the existing ones as deprecated.Signed-off-by: Rafael J. Wysocki
Acked-by: Pavel Machek
Signed-off-by: Len Brown
