* pm-cpufreq:
cpufreq: Make cpufreq_notify_transition & cpufreq_notify_post_transition static
cpufreq: Convert existing drivers to use cpufreq_freq_transition_{begin|end}
cpufreq: Make sure frequency transitions are serialized
intel_pstate: Use del_timer_sync in intel_pstate_cpu_stop
cpufreq: resume drivers before enabling governors
* acpica:
ACPICA: Enable auto-serialization as a default kernel behavior.
ACPICA: Ignore sync_level for methods that have been auto-serialized.
ACPICA: Add additional named objects for the auto-serialize method scan.
ACPICA: Add auto-serialization support for ill-behaved control methods.
ACPICA: Remove global option to serialize all control methods.
cpufreq_notify_transition() and cpufreq_notify_post_transition() shouldn't be
called directly by cpufreq drivers anymore and so these should be marked static.
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CPUFreq core has new infrastructure that would guarantee serialized calls to
target() or target_index() callbacks. These are called
cpufreq_freq_transition_begin() and cpufreq_freq_transition_end().
This patch converts existing drivers to use these new set of routines.
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Whenever we change the frequency of a CPU, we call the PRECHANGE and POSTCHANGE
notifiers. They must be serialized, i.e. PRECHANGE and POSTCHANGE notifiers
should strictly alternate, thereby preventing two different sets of PRECHANGE or
POSTCHANGE notifiers from interleaving arbitrarily.
The following examples illustrate why this is important:
Scenario 1:
-----------
A thread reading the value of cpuinfo_cur_freq, will call
__cpufreq_cpu_get()->cpufreq_out_of_sync()->cpufreq_notify_transition()
The ondemand governor can decide to change the frequency of the CPU at the same
time and hence it can end up sending the notifications via ->target().
If the notifiers are not serialized, the following sequence can occur:
- PRECHANGE Notification for freq A (from cpuinfo_cur_freq)
- PRECHANGE Notification for freq B (from target())
- Freq changed by target() to B
- POSTCHANGE Notification for freq B
- POSTCHANGE Notification for freq A
We can see from the above that the last POSTCHANGE Notification happens for freq
A but the hardware is set to run at freq B.
Where would we break then?: adjust_jiffies() in cpufreq.c & cpufreq_callback()
in arch/arm/kernel/smp.c (which also adjusts the jiffies). All the
loops_per_jiffy calculations will get messed up.
Scenario 2:
-----------
The governor calls __cpufreq_driver_target() to change the frequency. At the
same time, if we change scaling_{min|max}_freq from sysfs, it will end up
calling the governor's CPUFREQ_GOV_LIMITS notification, which will also call
__cpufreq_driver_target(). And hence we end up issuing concurrent calls to
->target().
Typically, platforms have the following logic in their ->target() routines:
(Eg: cpufreq-cpu0, omap, exynos, etc)
A. If new freq is more than old: Increase voltage
B. Change freq
C. If new freq is less than old: decrease voltage
Now, if the two concurrent calls to ->target() are X and Y, where X is trying to
increase the freq and Y is trying to decrease it, we get the following race
condition:
X.A: voltage gets increased for larger freq
Y.A: nothing happens
Y.B: freq gets decreased
Y.C: voltage gets decreased
X.B: freq gets increased
X.C: nothing happens
Thus we can end up setting a freq which is not supported by the voltage we have
set. That will probably make the clock to the CPU unstable and the system might
not work properly anymore.
This patch introduces a set of synchronization primitives to serialize frequency
transitions, which are to be used as shown below:
cpufreq_freq_transition_begin();
//Perform the frequency change
cpufreq_freq_transition_end();
The _begin() call sends the PRECHANGE notification whereas the _end() call sends
the POSTCHANGE notification. Also, all the necessary synchronization is handled
within these calls. In particular, even drivers which set the ASYNC_NOTIFICATION
flag can also use these APIs for performing frequency transitions (ie., you can
call _begin() from one task, and call the corresponding _end() from a different
task).
The actual synchronization underneath is not that complicated:
The key challenge is to allow drivers to begin the transition from one thread
and end it in a completely different thread (this is to enable drivers that do
asynchronous POSTCHANGE notification from bottom-halves, to also use the same
interface).
To achieve this, a 'transition_ongoing' flag, a 'transition_lock' spinlock and a
wait-queue are added per-policy. The flag and the wait-queue are used in
conjunction to create an "uninterrupted flow" from _begin() to _end(). The
spinlock is used to ensure that only one such "flow" is in flight at any given
time. Put together, this provides us all the necessary synchronization.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Ensure that no timer callback is running since we are about to free
the timer structure. We cannot guarantee that the call back is called
on the CPU where the timer is running.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
During suspend, we first stop governors and then suspend cpufreq drivers and
resume must be exactly opposite of that. i.e. resume drivers first and then
start governors.
But the current code in resume enables governors first and then resume drivers.
Fix it be changing code sequence there.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit df86f5df79 (ACPI / processor: Make it possible to get
APIC ID via GIC).
APIC ID refers the hardware ID of the CPU, which means MPIDR on
ARM/ARM64, but in ACPI 5.0, GIC ID feild in GIC structure have
no explicit definition and may not refer to the MPIDR.
Commit df86f5df79 assumed that gic->gic_id as MPIDR which may not be
the case, so revert it until the explicit definition of GIC structure
is ready.
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The previous commit "ACPICA: Add auto-serialization support for ill-behaved
control methods" introduced the auto-serialization facility as a workaround
that can be enabled by "acpi_auto_serialize":
This feature marks control methods that create named objects as "serialized"
to avoid unwanted AE_ALREADY_EXISTS control method evaluation failures.
Enable method auto-serialization as the default kernel behavior. The new kernel
parameter is also changed from "acpi_auto_serialize" to "acpi_no_auto_serialize"
to reflect the default behavior.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
References: http://www.spinics.net/lists/linux-acpi/msg49496.html
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cannot use a sync_level for methods that have been serialized at load-time
or runtime because this may interfere with any existing use of sync_levels
within the ASL code. So, we simply ignore the sync_level for these methods,
thus preserving any existing sync_level priorities. Note, the use of
sync_levels is actually rather rare within BIOS ASL code.
References: http://www.spinics.net/lists/linux-acpi/msg49496.html
Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Reported-by: Sabrina Dubroka <sd@queasysnail.net>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This change adds some additional opcodes that are detected and will
cause a method to be auto-serialized. These opcodes are the various
CreateXField and the FieldUnit opcodes. Lv Zheng.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This change adds support to automatically mark a control method as
"serialized" if the method creates any named objects. This will
positively prevent the method from being entered by more than one
thread and thus preventing a possible abort when an attempt is
made to create an object twice.
Implemented by parsing all non-serialize control methods at table
load time.
This feature is disabled by default and this patch also adds a new
Linux kernel parameter "acpi_auto_serialize" to allow this feature
to be turned on for a specific boot.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to the reports, the "acpi_serialize" mechanism is broken as:
A. The parallel method calls can still happen when the interpreter lock is
released under the following conditions:
1. External callbacks are invoked, for example, by the region handlers,
the exception handlers, etc.;
2. Module level execution is performed when Load/LoadTable opcodes are
executed, and
3. The _REG control methods are invoked to complete the region
registrations.
B. For the following situations, the interpreter lock need to be released
even for a serialized method while currently, the lock-releasing
operation is marked as a no-op by
acpi_ex_relinquish/reacquire_interpreter() when this mechanism is
enabled:
1. Wait opcode is executed,
2. Acquire opcode is executed, and
3. Sleep opcode is executed.
This patch removes this mechanism and the internal
acpi_ex_relinquish/reacquire_interpreter() APIs. Lv Zheng.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull devfreq fix for 3.15-rc1 from MyungJoo Ham.
* 'for-rafael' of git://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq:
PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs
* acpi-processor:
ACPI: Move BAD_MADT_ENTRY() to linux/acpi.h
ACPI / processor: Make it possible to get APIC ID via GIC
ACPI / processor: Build idle_boot_override on x86 and ia64
ACPI / processor: Use ACPI_PROCESSOR_DEVICE_HID instead of "ACPI0007"
ACPI / processor: Fix acpi_processor_eval_pdc() return value type
The current devfreq_update_status() has the following bugs:
- If previous frequency doesn't have a valid level, it does an out of bounds
access into the trans_table and causes memory corruption.
- When the new frequency doesn't have a valid level, the time spent in the
new frequency is counted towards the next valid frequency switch instead of
being ignored.
- The time spent on the previous frequency is added to the new frequency's
stats instead of the previous frequency's stats.
This patch fixes all of this.
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
This patch removes the use of the IRQF_DISABLED flag
from drivers/pnp/resource.c
It's a NOOP since 2.6.35 and it will be removed one day.
Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-cpufreq: (30 commits)
intel_pstate: Set core to min P state during core offline
cpufreq: Add stop CPU callback to cpufreq_driver interface
cpufreq: Remove unnecessary braces
cpufreq: Fix checkpatch errors and warnings
cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs
cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}
cpufreq: Do not allow ->setpolicy drivers to provide ->target
cpufreq: arm_big_little: set 'physical_cluster' for each CPU
cpufreq: arm_big_little: make vexpress driver depend on bL core driver
cpufreq: SPEAr: Instantiate as platform_driver
cpufreq: Remove unnecessary variable/parameter 'frozen'
cpufreq: Remove cpufreq_generic_exit()
cpufreq: add 'freq_table' in struct cpufreq_policy
cpufreq: Reformat printk() statements
cpufreq: Tegra: Use cpufreq_generic_suspend()
cpufreq: s5pv210: Use cpufreq_generic_suspend()
cpufreq: exynos: Use cpufreq_generic_suspend()
cpufreq: Implement cpufreq_generic_suspend()
cpufreq: suspend governors on system suspend/hibernate
cpufreq: move call to __find_governor() to cpufreq_init_policy()
...
* pm-cpuidle:
cpuidle: delay enabling interrupts until all coupled CPUs leave idle
cpuidle: poll state can measure residency
cpuidle: Move perf multiplier calculation out of the selection loop
cpuidle: Do not substract exit latency from assumed sleep length
cpuidle: Ensure menu coefficients stay within domain
cpuidle: Use actual state latency in menu governor
cpuidle: rename expected_us to next_timer_us in menu governor
rjw> Why exactly are they errors?
Geert> checkpatch.pl says: "WARNING: please, no space before tabs",
Vim (with "let c_space_errors=1") shows them in red.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Change to use the new ->stop_cpu() callback to do clean up during CPU
hotplug. The requested P state for an offline core will be used by the
hardware coordination function to select the package P state. If the
core is under load when it is offlined it will fix the package P state
floor to the requested P state of offline core.
Reported-by: Patrick Marlier <patrick.marlier@gmail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
[rjw: Minor modifications]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove unnecessary braces from a single statement.
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix 2 checkpatch errors about using assignment in if condition,
1 checkpatch error about a required space after comma
and 3 warnings about line over 80 characters.
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to the data provided by HW Team, at least 12 internal platform
clock cycles are required to stabilize a DFS clock switch on FSL e500mc Socs.
This patch replaces the CPUFREQ_ETERNAL with appropriate HW clock transition
latency to make DFS governors work normally on Freescale e500mc boards.
Signed-off-by: Zhuoyu Zhang <Zhuoyu.Zhang@freescale.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
For a few subsystems I am the person who actually applies patches
and people don't CC me on patch submissions, because my address is
not the first one in the given MAINTAINERS item.
Reorder PM and ACPI maintainer addresses in MAINTAINERS to make
the probability of that a bit smaller.
Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
As of commit 45f0a85c82 ('PM / Runtime: Rework the "runtime idle"
helper routine'), the return value of ->runtime_idle() is no longer
ignored by the PM core, but used to decide whether to suspend the
device or not.
Update the documentation to match the code.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It was only ever used by the ACPI video driver, and that only use case
vanished over 3 years ago (see commit 677bd810, "ACPI video: remove
output switching control".) So this is dead code and I guess we can
remove it now.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The fujitsu-laptop driver includes <linux/video_output.h> but doesn't
call any of its functions. Drop the unneeded include to avoid
unnecessary driver rebuilds.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Jonathan Woithe <jwoithe@just42.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI_VIDEO no longer depends on VIDEO_OUTPUT_CONTROL, so drivers which
want to select ACPI_VIDEO no longer have to select
VIDEO_OUTPUT_CONTROL.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI_VIDEO no longer depends on VIDEO_OUTPUT_CONTROL, so drivers which
want to select ACPI_VIDEO no longer have to select
VIDEO_OUTPUT_CONTROL.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI_VIDEO stopped depending on VIDEO_OUTPUT_CONTROL over 3 years ago
(see commit 677bd810, "ACPI video: remove output switching control".)
So it's about time to remove the Kconfig dependency between these two
options.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Two cpufreq notifiers CPUFREQ_RESUMECHANGE and CPUFREQ_SUSPENDCHANGE have
not been used for some time, so remove them to clean up code a bit.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq drivers that provide the ->setpolicy() callback are supposed
to have integrated governors, so they don't need to set ->target()
or ->target_index() and may confuse the core if any of these callbacks
is present.
For this reason, add a check preventing ->setpolicy cpufreq drivers
from registering if they have non-NULL ->target or ->target_index.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
We have a per-CPU variable for managing which cluster a CPU belongs to.
Currently, physical_cluster is set for policy->cpu only which leads to
the following on some SoC's:
- There are two clusters:
- Cluster 0 has four ARM Cortex A7 CPUs (slower ones): 0,1,2,3
- Cluster 1 has four ARM Cortex A15 CPUs (faster ones): 4,5,6,7
- CPUs are booted in order 0,1..7 and so initially policy->cpu for A7 cluster
would be 0 and for A15 cluster would be 4.
- Now CPU4 (i.e. A15_0) is hotplugged out and so policy->cpu for A15 cluster
becomes 5 (i.e. A15_1).
- But physical cluster is only set for CPU0 and CPU4 in ARM big LITTLE driver
and isn't updated.
- Now freq change request comes for A15 cluster and we would try to update freq
of physical_cluster of CPU5, i.e. A15_1. And it is currently set to zero
(default value of uninitialized global variables).
- And so we actually try to change freq of A7 cluster instead of A15.
- This also results in kernel crash as sometimes we might request freq above
A7's limit and CPU may behave badly..
Fix this by initializing physical_cluster for all CPUs of a policy.
Based on previous work by Xin Wang.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently vexpress big LITTLE driver selects ARM_BIG_LITTLE_CPUFREQ, so
if CONFIG_BIG_LITTLE isn't enabled and CONFIG_ARM_VEXPRESS_SPC_CPUFREQ
is enabled, we get the following build warnings:
warning: (ARM_VEXPRESS_SPC_CPUFREQ) selects ARM_BIG_LITTLE_CPUFREQ which has
unmet direct dependencies (ARCH_HAS_CPUFREQ && CPU_FREQ && (ARM || ARM64) && ARM
&& BIG_LITTLE && ARM_CPU_TOPOLOGY && HAVE_CLK)
To fix this, make ARM_VEXPRESS_SPC_CPUFREQ depend on ARM_BIG_LITTLE_CPUFREQ
instead of selecting it.
This also moves the entry for ARM_VEXPRESS_SPC_CPUFREQ along with other
big LITTLE config entries.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 1696d9d (ACPI: Remove the old /proc/acpi/event interface)
removed ACPI Button event which originally was sent to userspace via
/proc/acpi/event. This caused ACPI shutdown regression on gentoo
in VirtualBox. Now ACPI events are sent to userspace via netlink,
so add ACPI Button event back via netlink routine.
References: https://bugzilla.kernel.org/show_bug.cgi?id=71721
Reported-and-tested-by: Richard Musil <richard.musil@gmail.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We already have a macro for PREFIX of "ACPI: " in
drivers/acpi/internal.h, so remove the duplicate ones
in ACPI drivers when internal.h is included.
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On HP Pavilion dv6-6179er there are no notifications when AC adapter
is plugged/unplugged.
However, when AC status is read (acpi_ac_get_state), and if AC status
has changed, AML code triggers the notification.
This patch solves the problem by re-reading AC adapter status upon
ACPI_BATTERY_NOTIFY_STATUS notification.
Signed-off-by: Alexander Mezin <mezin.alexander@gmail.com>
Acked-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Allow other drivers to subscribe to battery status notifications.
Just like AC driver does.
Signed-off-by: Alexander Mezin <mezin.alexander@gmail.com>
Acked-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI_BATTERY_CLASS is used in multiple places.
Also, I'll use ACPI_BATTERY_NOTIFY_STATUS inside AC driver in
one of following patches.
So, create a header file and move ACPI_BATTERY_CLASS and
ACPI_BATTERY_NOTIFY_* definitions into it.
Also, remove copy of ACPI_BATTERY_CLASS from sbs.c
Signed-off-by: Alexander Mezin <mezin.alexander@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This reverts commit aae576e5faefa8ba70647efa320d4747b6375f1e.
Push and Pop are not portable "enough", and caused problems for
some ACPICA customers.
Signed-off-by: Robert Moore <Robert.Moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>