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The only reason that remains, to why the ARM cpuidle driver calls
cpuidle_register_driver(), is to avoid printing an error message in case
another driver already have been registered for the CPU. This seems a bit
silly, but more importantly, if that is a common scenario, perhaps we
should change cpuidle_register() accordingly instead.
In either case, let's consolidate the code, by converting to use
cpuidle_register|unregister(), which also avoids the unnecessary allocation
of the struct cpuidle_device.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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There's no point to register the cpuidle driver for the current CPU, when
the initialization of the arch specific back-end data fails by returning
-ENXIO.
Instead, let's re-order the sequence to its original flow, by first trying
to initialize the back-end part and then act accordingly on the returned
error code. Additionally, let's print the error message, no matter of what
error code that was returned.
Fixes: a0d46a3dfdc3 (ARM: cpuidle: Register per cpuidle device)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: 4.19+ <stable@vger.kernel.org> # v4.19+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull more power management updates from Rafael Wysocki:
"These remove a questionable heuristic from the menu cpuidle governor,
fix a recent build regression in the intel_pstate driver, clean up ARM
big-Little support in cpufreq and fix up hung task watchdog's
interaction with system-wide power management transitions.
Specifics:
- Fix build regression in the intel_pstate driver that doesn't build
without CONFIG_ACPI after recent changes (Dominik Brodowski).
- One of the heuristics in the menu cpuidle governor is based on a
function returning 0 most of the time, so drop it and clean up the
scheduler code related to it (Daniel Lezcano).
- Prevent the arm_big_little cpufreq driver from being used on ARM64
which is not suitable for it and drop the arm_big_little_dt driver
that is not used any more (Sudeep Holla).
- Prevent the hung task watchdog from triggering during resume from
system-wide sleep states by disabling it before freezing tasks and
enabling it again after they have been thawed (Vitaly Kuznetsov)"
* tag 'pm-4.20-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
kernel: hung_task.c: disable on suspend
cpufreq: remove unused arm_big_little_dt driver
cpufreq: drop ARM_BIG_LITTLE_CPUFREQ support for ARM64
cpufreq: intel_pstate: Fix compilation for !CONFIG_ACPI
cpuidle: menu: Remove get_loadavg() from the performance multiplier
sched: Factor out nr_iowait and nr_iowait_cpu
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There are several definitions of those functions/macros in places that
mess with fixed-point load averages. Provide an official version.
[akpm@linux-foundation.org: fix missed conversion in block/blk-iolatency.c]
Link: http://lkml.kernel.org/r/20180828172258.3185-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Tested-by: Daniel Drake <drake@endlessm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Enderborg <peter.enderborg@sony.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The function get_loadavg() returns almost always zero. To be more
precise, statistically speaking for a total of 1023379 times passing
in the function, the load is equal to zero 1020728 times, greater than
100, 610 times, the remaining is between 0 and 5.
In 2011, the get_loadavg() was removed from the Android tree because
of the above [1]. At this time, the load was:
unsigned long this_cpu_load(void)
{
struct rq *this = this_rq();
return this->cpu_load[0];
}
In 2014, the code was changed by commit 372ba8cb46b2 (cpuidle: menu: Lookup CPU
runqueues less) and the load is:
void get_iowait_load(unsigned long *nr_waiters, unsigned long *load)
{
struct rq *rq = this_rq();
*nr_waiters = atomic_read(&rq->nr_iowait);
*load = rq->load.weight;
}
with the same result.
Both measurements show using the load in this code path does no matter
anymore. Removing it.
[1] https://android.googlesource.com/kernel/common/+/4dedd9f124703207895777ac6e91dacde0f7cc17
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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If the minimum interval taken into account in the average computation
loop in get_typical_interval() is less than the expected idle
duration determined so far, the resultant average cannot be greater
than that value as well and the entire return result of the function
is going to be discarded anyway going forward.
In that case, it is a waste of time to carry out the remaining
computations in get_typical_interval(), so avoid that by returning
early if the minimum interval is not below the expected idle duration.
No intentional changes of behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Since the correction factor cannot be greater than RESOLUTION * DECAY,
the result of the predicted_us computation in menu_select() cannot be
greater than data->next_timer_us, so it is not necessary to compare
the "typical interval" value coming from get_typical_interval() with
data->next_timer_us separately.
It is sufficient to copmare predicted_us with the return value of
get_typical_interval() directly, so do that and drop the now
redundant expected_interval variable.
No intentional changes of behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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After some recent menu governor changes, the promotion of the
"polling" state to a physical one is mostly controlled by the
latency limit (resulting from the "interactivity" factor) and
not by the time to the closest timer event, so it should be
sufficient to check the exit latency of that state for this
purpose (of course, its target residency still needs to be
within the next timer event range for energy-efficiency).
Also, the physical state the "polling" one is promoted to need not
be the next one in principle (in case the next state is disabled,
for example).
For these reasons, simplify the checks made to decide whether or
not to promote the "polling" state to a physical one and update
the target idle duration when it is promoted in case the residency
of the new state turns out to be above the tick boundary (in which
case there is no reason to stop the tick).
Tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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If need_resched() returns "false", breaking out of the loop in
poll_idle() will cause a new idle state to be selected, so in fact
it usually doesn't make sense to spin in it longer than the target
residency of the second state. [Note that the "polling" state is
used only if there is at least one "real" state defined in addition
to it, so the second state is always there.] On the other hand,
breaking out of it early (say in case the next state is disabled)
shouldn't hurt as it is polling anyway.
For this reason, make the loop in poll_idle() break if the CPU has
been spinning longer than the target residency of the second state
(the "polling" state can only be state[0]).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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It is better to always update data->bucket before returning from
menu_select() to avoid updating the correction factor for a stale
bucket, so combine the latency_req == 0 special check with the more
general check below.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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If the next timer event (not including the tick) is closer than the
target residency of the second state or the PM QoS latency constraint
is below its exit latency, state[0] will be used regardless of any
other factors, so skip the computations in menu_select() then and
return 0 straight away from it.
Still, do that after the bucket has been determined to avoid
updating the correction factor for a stale bucket.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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It is not necessary to update data->last_state_idx in menu_select()
as it only is used in menu_update() which only runs when
data->needs_update is set and that is set only when updating
data->last_state_idx in menu_reflect().
Accordingly, drop the update of data->last_state_idx from
menu_select() and get rid of the (now redundant) "out" label
from it.
No intentional behavior changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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Rearrange the code in menu_select() so that the loop over idle states
always starts from 0 and get rid of the first_idx variable.
While at it, add two empty lines to separate conditional statements
from one another.
No intentional behavior changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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Since menu_select() can only set first_idx to 1 if the exit latency
of the second state is not greater than the latency limit, it should
first determine that limit. Thus first_idx should be computed after
the "interactivity" factor has been taken into account.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewedy-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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If the CPU exits the "polling" state due to the time limit in the
loop in poll_idle(), this is not a real wakeup and it just means
that the "polling" state selection was not adequate. The governor
mispredicted short idle duration, but had a more suitable state been
selected, the CPU might have spent more time in it. In fact, there
is no reason to expect that there would have been a wakeup event
earlier than the next timer in that case.
Handling such cases as regular wakeups in menu_update() may cause the
menu governor to make suboptimal decisions going forward, but ignoring
them altogether would not be correct either, because every time
menu_select() is invoked, it makes a separate new attempt to predict
the idle duration taking distinct time to the closest timer event as
input and the outcomes of all those attempts should be recorded.
For this reason, make menu_update() always assume that if the
"polling" state was exited due to the time limit, the next proper
wakeup event for the CPU would be the next timer event (not
including the tick).
Fixes: a37b969a61c1 "cpuidle: poll_state: Add time limit to poll_idle()"
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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The predicted_us field in struct menu_device is only accessed in
menu_select(), so replace it with a local variable in that function.
With that, stop using expected_interval instead of predicted_us to
store the new predicted idle duration value if it is set to the
selected state's target residency which is quite confusing.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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Currently, ktime_us_delta() is invoked unconditionally to compute the
idle residency of the CPU, but it only makes sense to do that if a
valid idle state has been entered, so move the ktime_us_delta()
invocation after the entered_state >= 0 check.
While at it, merge two comment blocks in there into one and drop
a space between type casting of diff.
This patch has no functional changes.
Signed-off-by: Fieah Lim <kw@fieahl.im>
[ rjw: Changelog cleanup, comment format fix ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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cpuidle_get_last_residency() is just a wrapper for retrieving
the last_residency member of struct cpuidle_device. It's also
weirdly the only wrapper function for accessing cpuidle_* struct
member (by my best guess is it could be a leftover from v2.x).
Anyhow, since the only two users (the ladder and menu governors)
can access dev->last_residency directly, and it's more intuitive to
do it that way, let's just get rid of the wrapper.
This patch tidies up CPU idle code a bit without functional changes.
Signed-off-by: Fieah Lim <kw@fieahl.im>
[ rjw: Changelog cleanup ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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The case addressed by commit 5ef499cd571c (cpuidle: menu: Handle
stopped tick more aggressively) in the stopped tick case is present
when the tick has not been stopped yet too. Namely, if only two CPU
idle states, shallow state A with target residency significantly
below the tick boundary and deep state B with target residency
significantly above it, are available and the predicted idle
duration is above the tick boundary, but below the target residency
of state B, state A will be selected and the CPU may spend indefinite
amount of time in it, which is not quite energy-efficient.
However, if the tick has not been stopped yet and the governor is
about to select a shallow idle state for the CPU even though the idle
duration predicted by it is above the tick boundary, it should be
fine to wake up the CPU early, so the tick can be retained then and
the governor will have a chance to select a deeper state when it runs
next time.
[Note that when this really happens, it will make the idle duration
predictor believe that the CPU might be idle longer than predicted,
which will make it more likely to predict longer idle durations going
forward, but that will also cause deeper idle states to be selected
going forward, on average, which is what's needed here.]
Fixes: 87c9fe6ee495 (cpuidle: menu: Avoid selecting shallow states with stopped tick)
Reported-by: Leo Yan <leo.yan@linaro.org>
Cc: 4.17+ <stable@vger.kernel.org> # 4.17+: 5ef499cd571c (cpuidle: menu: Handle ...)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull more power management updates from Rafael Wysocki:
"These fix the main idle loop and the menu cpuidle governor, clean up
the latter, fix a mistake in the PCI bus type's support for system
suspend and resume, fix the ondemand and conservative cpufreq
governors, address a build issue in the system wakeup framework and
make the ACPI C-states desciptions less confusing.
Specifics:
- Make the idle loop handle stopped scheduler tick correctly (Rafael
Wysocki).
- Prevent the menu cpuidle governor from letting CPUs spend too much
time in shallow idle states when it is invoked with scheduler tick
stopped and clean it up somewhat (Rafael Wysocki).
- Avoid invoking the platform firmware to make the platform enter the
ACPI S3 sleep state with suspended PCIe root ports which may
confuse the firmware and cause it to crash (Rafael Wysocki).
- Fix sysfs-related race in the ondemand and conservative cpufreq
governors which may cause the system to crash if the governor
module is removed during an update of CPU frequency limits (Henry
Willard).
- Select SRCU when building the system wakeup framework to avoid a
build issue in it (zhangyi).
- Make the descriptions of ACPI C-states vendor-neutral to avoid
confusion (Prarit Bhargava)"
* tag 'pm-4.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpuidle: menu: Handle stopped tick more aggressively
sched: idle: Avoid retaining the tick when it has been stopped
PCI / ACPI / PM: Resume all bridges on suspend-to-RAM
cpuidle: menu: Update stale polling override comment
cpufreq: governor: Avoid accessing invalid governor_data
x86/ACPI/cstate: Make APCI C1 FFH MWAIT C-state description vendor-neutral
cpuidle: menu: Fix white space
PM / sleep: wakeup: Fix build error caused by missing SRCU support
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Commit 87c9fe6ee495 (cpuidle: menu: Avoid selecting shallow states
with stopped tick) missed the case when the target residencies of
deep idle states of CPUs are above the tick boundary which may cause
the CPU to get stuck in a shallow idle state for a long time.
Say there are two CPU idle states available: one shallow, with the
target residency much below the tick boundary and one deep, with
the target residency significantly above the tick boundary. In
that case, if the tick has been stopped already and the expected
next timer event is relatively far in the future, the governor will
assume the idle duration to be equal to TICK_USEC and it will select
the idle state for the CPU accordingly. However, that will cause the
shallow state to be selected even though it would have been more
energy-efficient to select the deep one.
To address this issue, modify the governor to always use the time
till the closest timer event instead of the predicted idle duration
if the latter is less than the tick period length and the tick has
been stopped already. Also make it extend the search for a matching
idle state if the tick is stopped to avoid settling on a shallow
state if deep states with target residencies above the tick period
length are available.
In addition, make it always indicate that the tick should be stopped
if it has been stopped already for consistency.
Fixes: 87c9fe6ee495 (cpuidle: menu: Avoid selecting shallow states with stopped tick)
Reported-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: 4.17+ <stable@vger.kernel.org> # 4.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull powerpc updates from Michael Ellerman:
"Notable changes:
- A fix for a bug in our page table fragment allocator, where a page
table page could be freed and reallocated for something else while
still in use, leading to memory corruption etc. The fix reuses
pt_mm in struct page (x86 only) for a powerpc only refcount.
- Fixes to our pkey support. Several are user-visible changes, but
bring us in to line with x86 behaviour and/or fix outright bugs.
Thanks to Florian Weimer for reporting many of these.
- A series to improve the hvc driver & related OPAL console code,
which have been seen to cause hardlockups at times. The hvc driver
changes in particular have been in linux-next for ~month.
- Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y.
- Remove Power8 DD1 and Power9 DD1 support, neither chip should be in
use anywhere other than as a paper weight.
- An optimised memcmp implementation using Power7-or-later VMX
instructions
- Support for barrier_nospec on some NXP CPUs.
- Support for flushing the count cache on context switch on some IBM
CPUs (controlled by firmware), as a Spectre v2 mitigation.
- A series to enhance the information we print on unhandled signals
to bring it into line with other arches, including showing the
offending VMA and dumping the instructions around the fault.
Thanks to: Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey
Kardashevskiy, Alexey Spirkov, Alistair Popple, Andrew Donnellan,
Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Bartosz Golaszewski,
Benjamin Herrenschmidt, Bharat Bhushan, Bjoern Noetel, Boqun Feng,
Breno Leitao, Bryant G. Ly, Camelia Groza, Christophe Leroy, Christoph
Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt, Darren Stevens, Dave
Young, David Gibson, Diana Craciun, Finn Thain, Florian Weimer,
Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand,
Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel
Stanley, Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh
Salgaonkar, Markus Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues,
Michael Hanselmann, Michael Neuling, Michael Schmitz, Mukesh Ojha,
Murilo Opsfelder Araujo, Nicholas Piggin, Parth Y Shah, Paul
Mackerras, Paul Menzel, Ram Pai, Randy Dunlap, Rashmica Gupta, Reza
Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff, Scott Wood,
Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson, Thiago
Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat
Rao, zhong jiang"
* tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (234 commits)
powerpc/mm/book3s/radix: Add mapping statistics
powerpc/uaccess: Enable get_user(u64, *p) on 32-bit
powerpc/mm/hash: Remove unnecessary do { } while(0) loop
powerpc/64s: move machine check SLB flushing to mm/slb.c
powerpc/powernv/idle: Fix build error
powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range
powerpc/mm: remove warning about ‘type’ being set
powerpc/32: Include setup.h header file to fix warnings
powerpc: Move `path` variable inside DEBUG_PROM
powerpc/powermac: Make some functions static
powerpc/powermac: Remove variable x that's never read
cxl: remove a dead branch
powerpc/powermac: Add missing include of header pmac.h
powerpc/kexec: Use common error handling code in setup_new_fdt()
powerpc/xmon: Add address lookup for percpu symbols
powerpc/mm: remove huge_pte_offset_and_shift() prototype
powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled
powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.
powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements
powerpc/fadump: handle crash memory ranges array index overflow
...
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The comment to explain why the menu governor uses idle state 1
instead of idle state 0 as the first one sometimes is stale (among
other things it mentions a user setting not present any more),
so update it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Fix some damaged white space in menu_select().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Export pnv_idle_states and nr_pnv_idle_states so that its accessible to
cpuidle driver. Use properties from pnv_idle_states structure for powernv
cpuidle_init.
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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It's perfectly fine to have multiple cpuidle driver compiled in the
build configuration. However, it's not good to throw error on driver
registration failure if some other driver is already initialised and
assigned. In such cases, __cpuidle_register_driver returns -EBUSY and
we can check for such error before throwing the error.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull powerpc updates from Michael Ellerman:
"Notable changes:
- Support for split PMD page table lock on 64-bit Book3S (Power8/9).
- Add support for HAVE_RELIABLE_STACKTRACE, so we properly support
live patching again.
- Add support for patching barrier_nospec in copy_from_user() and
syscall entry.
- A couple of fixes for our data breakpoints on Book3S.
- A series from Nick optimising TLB/mm handling with the Radix MMU.
- Numerous small cleanups to squash sparse/gcc warnings from Mathieu
Malaterre.
- Several series optimising various parts of the 32-bit code from
Christophe Leroy.
- Removal of support for two old machines, "SBC834xE" and "C2K"
("GEFanuc,C2K"), which is why the diffstat has so many deletions.
And many other small improvements & fixes.
There's a few out-of-area changes. Some minor ftrace changes OK'ed by
Steve, and a fix to our powernv cpuidle driver. Then there's a series
touching mm, x86 and fs/proc/task_mmu.c, which cleans up some details
around pkey support. It was ack'ed/reviewed by Ingo & Dave and has
been in next for several weeks.
Thanks to: Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al
Viro, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd
Bergmann, Balbir Singh, Cédric Le Goater, Christophe Leroy, Christophe
Lombard, Colin Ian King, Dave Hansen, Fabio Estevam, Finn Thain,
Frederic Barrat, Gautham R. Shenoy, Haren Myneni, Hari Bathini, Ingo
Molnar, Jonathan Neuschäfer, Josh Poimboeuf, Kamalesh Babulal,
Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu Malaterre,
Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica
Gupta, Ravi Bangoria, Russell Currey, Sam Bobroff, Samuel
Mendoza-Jonas, Segher Boessenkool, Shilpasri G Bhat, Simon Guo,
Souptick Joarder, Stewart Smith, Thiago Jung Bauermann, Torsten Duwe,
Vaibhav Jain, Wei Yongjun, Wolfram Sang, Yisheng Xie, YueHaibing"
* tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (251 commits)
powerpc/64s/radix: Fix missing ptesync in flush_cache_vmap
cpuidle: powernv: Fix promotion from snooze if next state disabled
powerpc: fix build failure by disabling attribute-alias warning in pci_32
ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait()
powerpc-opal: fix spelling mistake "Uniterrupted" -> "Uninterrupted"
powerpc: fix spelling mistake: "Usupported" -> "Unsupported"
powerpc/pkeys: Detach execute_only key on !PROT_EXEC
powerpc/powernv: copy/paste - Mask SO bit in CR
powerpc: Remove core support for Marvell mv64x60 hostbridges
powerpc/boot: Remove core support for Marvell mv64x60 hostbridges
powerpc/boot: Remove support for Marvell mv64x60 i2c controller
powerpc/boot: Remove support for Marvell MPSC serial controller
powerpc/embedded6xx: Remove C2K board support
powerpc/lib: optimise PPC32 memcmp
powerpc/lib: optimise 32 bits __clear_user()
powerpc/time: inline arch_vtime_task_switch()
powerpc/Makefile: set -mcpu=860 flag for the 8xx
powerpc: Implement csum_ipv6_magic in assembly
powerpc/32: Optimise __csum_partial()
powerpc/lib: Adjust .balign inside string functions for PPC32
...
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The commit 78eaa10f027c ("cpuidle: powernv/pseries: Auto-promotion of
snooze to deeper idle state") introduced a timeout for the snooze idle
state so that it could be eventually be promoted to a deeper idle
state. The snooze timeout value is static and set to the target
residency of the next idle state, which would train the cpuidle
governor to pick the next idle state eventually.
The unfortunate side-effect of this is that if the next idle state(s)
is disabled, the CPU will forever remain in snooze, despite the fact
that the system is completely idle, and other deeper idle states are
available.
This patch fixes the issue by dynamically setting the snooze timeout
to the target residency of the next enabled state on the device.
Before Patch:
POWER8 : Only nap disabled.
$ cpupower monitor sleep 30
sleep took 30.01297 seconds and exited with status 0
|Idle_Stats
PKG |CORE|CPU | snoo | Nap | Fast
0| 8| 0| 96.41| 0.00| 0.00
0| 8| 1| 96.43| 0.00| 0.00
0| 8| 2| 96.47| 0.00| 0.00
0| 8| 3| 96.35| 0.00| 0.00
0| 8| 4| 96.37| 0.00| 0.00
0| 8| 5| 96.37| 0.00| 0.00
0| 8| 6| 96.47| 0.00| 0.00
0| 8| 7| 96.47| 0.00| 0.00
POWER9: Shallow states (stop0lite, stop1lite, stop2lite, stop0, stop1,
stop2) disabled:
$ cpupower monitor sleep 30
sleep took 30.05033 seconds and exited with status 0
|Idle_Stats
PKG |CORE|CPU | snoo | stop | stop | stop | stop | stop | stop | stop | stop
0| 16| 0| 89.79| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00
0| 16| 1| 90.12| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00
0| 16| 2| 90.21| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00
0| 16| 3| 90.29| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00
After Patch:
POWER8 : Only nap disabled.
$ cpupower monitor sleep 30
sleep took 30.01200 seconds and exited with status 0
|Idle_Stats
PKG |CORE|CPU | snoo | Nap | Fast
0| 8| 0| 16.58| 0.00| 77.21
0| 8| 1| 18.42| 0.00| 75.38
0| 8| 2| 4.70| 0.00| 94.09
0| 8| 3| 17.06| 0.00| 81.73
0| 8| 4| 3.06| 0.00| 95.73
0| 8| 5| 7.00| 0.00| 96.80
0| 8| 6| 1.00| 0.00| 98.79
0| 8| 7| 5.62| 0.00| 94.17
POWER9: Shallow states (stop0lite, stop1lite, stop2lite, stop0, stop1,
stop2) disabled:
$ cpupower monitor sleep 30
sleep took 30.02110 seconds and exited with status 0
|Idle_Stats
PKG |CORE|CPU | snoo | stop | stop | stop | stop | stop | stop | stop | stop
0| 0| 0| 0.69| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 9.39| 89.70
0| 0| 1| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.05| 93.21
0| 0| 2| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 89.93
0| 0| 3| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 93.26
Fixes: 78eaa10f027c ("cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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There is some code duplication related to the PM QoS handling between
the existing cpuidle governors, so move that code to a common helper
function and call that from the governors.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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PM_QOS_RESUME_LATENCY_NO_CONSTRAINT is defined as the 32-bit integer
maximum, so it is not necessary to test the return value of
dev_pm_qos_raw_read_value() against it directly in the menu and
ladder cpuidle governors.
Drop these redundant checks.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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If the scheduler tick has been stopped already and the governor
selects a shallow idle state, the CPU can spend a long time in that
state if the selection is based on an inaccurate prediction of idle
time. That effect turns out to be relevant, so it needs to be
mitigated.
To that end, modify the menu governor to discard the result of the
idle time prediction if the tick is stopped and the predicted idle
time is less than the tick period length, unless the tick timer is
going to expire soon.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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If the tick isn't stopped, the target residency of the state selected
by the menu governor may be greater than the actual time to the next
tick and that means lost energy.
To avoid that, make tick_nohz_get_sleep_length() return the current
time to the next event (before stopping the tick) in addition to the
estimated one via an extra pointer argument and make menu_select()
use that value to refine the state selection when necessary.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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Add a new pointer argument to cpuidle_select() and to the ->select
cpuidle governor callback to allow a boolean value indicating
whether or not the tick should be stopped before entering the
selected state to be returned from there.
Make the ladder governor ignore that pointer (to preserve its
current behavior) and make the menu governor return 'false" through
it if:
(1) the idle exit latency is constrained at 0, or
(2) the selected state is a polling one, or
(3) the expected idle period duration is within the tick period
range.
In addition to that, the correction factor computations in the menu
governor need to take the possibility that the tick may not be
stopped into account to avoid artificially small correction factor
values. To that end, add a mechanism to record tick wakeups, as
suggested by Peter Zijlstra, and use it to modify the menu_update()
behavior when tick wakeup occurs. Namely, if the CPU is woken up by
the tick and the return value of tick_nohz_get_sleep_length() is not
within the tick boundary, the predicted idle duration is likely too
short, so make menu_update() try to compensate for that by updating
the governor statistics as though the CPU was idle for a long time.
Since the value returned through the new argument pointer of
cpuidle_select() is not used by its caller yet, this change by
itself is not expected to alter the functionality of the code.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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Rik reports that he sees an increase in CPU use in one benchmark
due to commit 612f1a22f067 "cpuidle: poll_state: Add time limit to
poll_idle()" that caused poll_idle() to call local_clock() in every
iteration of the loop. Utilization increase generally means more
non-idle time with respect to total CPU time (on the average) which
implies reduced CPU frequency.
Doug reports that limiting the rate of local_clock() invocations
in there causes much less power to be drawn during a CPU-intensive
parallel workload (with idle states 1 and 2 disabled to enforce more
state 0 residency).
These two reports together suggest that executing local_clock() on
multiple CPUs in parallel at a high rate may cause chips to get hot
and trigger thermal/power limits on them to kick in, so reduce the
rate of local_clock() invocations in poll_idle() to avoid that issue.
Fixes: 612f1a22f067 "cpuidle: poll_state: Add time limit to poll_idle()"
Reported-by: Rik van Riel <riel@surriel.com>
Reported-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
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Add a new attribute group called "s2idle" under the sysfs directory
of each cpuidle state that supports the ->enter_s2idle callback
and put two new attributes, "usage" and "time", into that group to
represent the number of times the given state was requested for
suspend-to-idle and the total time spent in suspend-to-idle after
requesting that state, respectively.
That will allow diagnostic information related to suspend-to-idle
to be collected without enabling advanced debug features and
analyzing dmesg output.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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All the needed code has been already merged to mach-exynos core in
commit af9971144dde ("ARM: EXYNOS: add coupled cpuidle support for
Exynos3250"), so enable support for coupled variant also for Exynos3250
SoCs.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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If poll_idle() is allowed to spin until need_resched() returns 'true',
it may actually spin for a much longer time than expected by the idle
governor, since set_tsk_need_resched() is not always called by the
timer interrupt handler. If that happens, the CPU may spend much
more time than anticipated in the "polling" state.
To prevent that from happening, limit the time of the spinning loop
in poll_idle().
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Doug Smythies <dsmythies@telus.net>
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Omit an extra message for a memory allocation failure in this function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull powerpc updates from Michael Ellerman:
"Highlights:
- Enable support for memory protection keys aka "pkeys" on Power7/8/9
when using the hash table MMU.
- Extend our interrupt soft masking to support masking PMU interrupts
as well as "normal" interrupts, and then use that to implement
local_t for a ~4x speedup vs the current atomics-based
implementation.
- A new driver "ocxl" for "Open Coherent Accelerator Processor
Interface (OpenCAPI)" devices.
- Support for new device tree properties on PowerVM to describe
hotpluggable memory and devices.
- Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit
VDSO.
- Freescale updates from Scott: fixes for CPM GPIO and an FSL PCI
erratum workaround, plus a minor cleanup patch.
As well as quite a lot of other changes all over the place, and small
fixes and cleanups as always.
Thanks to: Alan Modra, Alastair D'Silva, Alexey Kardashevskiy,
Alistair Popple, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
Anju T Sudhakar, Anshuman Khandual, Anton Blanchard, Arnd Bergmann,
Balbir Singh, Benjamin Herrenschmidt, Bhaktipriya Shridhar, Bryant G.
Ly, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Cyril Bur,
David Gibson, Desnes A. Nunes do Rosario, Dmitry Torokhov, Frederic
Barrat, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo A. R. Silva,
Gustavo Romero, Ivan Mikhaylov, Joakim Tjernlund, Joe Perches, Josh
Poimboeuf, Juan J. Alvarez, Julia Cartwright, Kamalesh Babulal,
Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael
Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud,
Ram Pai, Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee,
Simon Guo, Stewart Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann,
Vaibhav Jain, Vasyl Gomonovych"
* tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (199 commits)
powerpc/mm/radix: Fix build error when RADIX_MMU=n
macintosh/ams-input: Use true and false for boolean values
macintosh: change some data types from int to bool
powerpc/watchdog: Print the NIP in soft_nmi_interrupt()
powerpc/watchdog: regs can't be null in soft_nmi_interrupt()
powerpc/watchdog: Tweak watchdog printks
powerpc/cell: Remove axonram driver
rtc-opal: Fix handling of firmware error codes, prevent busy loops
powerpc/mpc52xx_gpt: make use of raw_spinlock variants
macintosh/adb: Properly mark continued kernel messages
powerpc/pseries: Fix cpu hotplug crash with memoryless nodes
powerpc/numa: Ensure nodes initialized for hotplug
powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
powerpc/kernel: Block interrupts when updating TIDR
powerpc/powernv/idoa: Remove unnecessary pcidev from pci_dn
powerpc/mm/nohash: do not flush the entire mm when range is a single page
powerpc/pseries: Add Initialization of VF Bars
powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV
powerpc/eeh: Add EEH notify resume sysfs
powerpc/eeh: Add EEH operations to notify resume
...
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For shared processor guests (e.g., KVM), add an idle polling mode rather
than immediately returning to the hypervisor when the guest CPU goes
idle.
Test setup is a 2 socket POWER9 with 4 guests running, each with vCPUs
equal to 1/2 of real of CPUs. Saturated each guest with tbench. Using
polling idle gives about 1.4x throughput.
Kernel compile speed was not changed significantly.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Since e1689795a7 ("cpuidle: Add common time keeping and irq enabling"),
cpuidle drivers are expected to return from ->enter with irqs disabled.
Update the cpuidle-powernv snooze and cede loops to disable irqs before
returning.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Since e1689795a7 ("cpuidle: Add common time keeping and irq enabling"),
cpuidle drivers are expected to return from ->enter with irqs disabled.
Update the cpuidle-powernv snooze loop to disable irqs before returning.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Checks if the new governor is NULL before updating the
cupidle_curr_governor.
Signed-off-by: gaurav jindal <gauravjindal1104@gmail.com>
[ rjw : Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Pull powerpc updates from Michael Ellerman:
"A bit of a small release, I suspect in part due to me travelling for
KS. But my backlog of patches to review is smaller than usual, so I
think in part folks just didn't send as much this cycle.
Non-highlights:
- Five fixes for the >128T address space handling, both to fix bugs
in our implementation and to bring the semantics exactly into line
with x86.
Highlights:
- Support for a new OPAL call on bare metal machines which gives us a
true NMI (ie. is not masked by MSR[EE]=0) for debugging etc.
- Support for Power9 DD2 in the CXL driver.
- Improvements to machine check handling so that uncorrectable errors
can be reported into the generic memory_failure() machinery.
- Some fixes and improvements for VPHN, which is used under PowerVM
to notify the Linux partition of topology changes.
- Plumbing to enable TM (transactional memory) without suspend on
some Power9 processors (PPC_FEATURE2_HTM_NO_SUSPEND).
- Support for emulating vector loads form cache-inhibited memory, on
some Power9 revisions.
- Disable the fast-endian switch "syscall" by default (behind a
CONFIG), we believe it has never had any users.
- A major rework of the API drivers use when initiating and waiting
for long running operations performed by OPAL firmware, and changes
to the powernv_flash driver to use the new API.
- Several fixes for the handling of FP/VMX/VSX while processes are
using transactional memory.
- Optimisations of TLB range flushes when using the radix MMU on
Power9.
- Improvements to the VAS facility used to access coprocessors on
Power9, and related improvements to the way the NX crypto driver
handles requests.
- Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit.
Thanks to: Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew
Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin
Herrenschmidt, Breno Leitao, Christophe Leroy, Christophe Lombard,
Cyril Bur, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven,
Guilherme G. Piccoli, Gustavo Romero, Haren Myneni, Joel Stanley,
Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami Hiramatsu,
Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao,
Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia
Franco de Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee,
Shriya, Stephen Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel
Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, and William A.
Kennington III"
* tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (151 commits)
powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature
powerpc/64s: Fix masking of SRR1 bits on instruction fault
powerpc/64s: mm_context.addr_limit is only used on hash
powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation
powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary
powerpc/64s/hash: Fix fork() with 512TB process address space
powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation
powerpc/64s/hash: Fix 512T hint detection to use >= 128T
powerpc: Fix DABR match on hash based systems
powerpc/signal: Properly handle return value from uprobe_deny_signal()
powerpc/fadump: use kstrtoint to handle sysfs store
powerpc/lib: Implement UACCESS_FLUSHCACHE API
powerpc/lib: Implement PMEM API
powerpc/powernv/npu: Don't explicitly flush nmmu tlb
powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm()
powerpc/powernv/idle: Round up latency and residency values
powerpc/kprobes: refactor kprobe_lookup_name for safer string operations
powerpc/kprobes: Blacklist emulate_update_regs() from kprobes
powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace
powerpc/kprobes: Disable preemption before invoking probe handler for optprobes
...
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* pm-cpuidle:
intel_idle: Graceful probe failure when MWAIT is disabled
cpuidle: Avoid assignment in if () argument
cpuidle: Clean up cpuidle_enable_device() error handling a bit
cpuidle: ladder: Add per CPU PM QoS resume latency support
ARM: cpuidle: Refactor rollback operations if init fails
ARM: cpuidle: Correct driver unregistration if init fails
intel_idle: replace conditionals with static_cpu_has(X86_FEATURE_ARAT)
cpuidle: fix broadcast control when broadcast can not be entered
Conflicts:
drivers/idle/intel_idle.c
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* pm-qos:
PM / QoS: Fix device resume latency framework
PM / QoS: Drop PM_QOS_FLAG_REMOTE_WAKEUP
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On PowerNV platforms, firmware provides exit latency and
target residency for each of the idle states in nano
seconds. Cpuidle framework expects the values in micro
seconds. Round up to nearest micro seconds to avoid errors
in cases where the values are defined as fractional micro
seconds.
Default idle state of 'snooze' has exit latency of zero. If
other states have fractional micro second exit latency, they
would get rounded down to zero micro second and make cpuidle
framework choose deeper idle state when snooze loop is the
right choice.
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Clean up cpuidle_enable_device() to avoid doing an assignment
in an expression evaluated as an argument of if (), which also
makes the code in question more readable.
Signed-off-by: Gaurav Jindal <gauravjindal1104@gmail.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Do not fetch per CPU drv if cpuidle_curr_governor is NULL
to avoid useless per CPU processing.
Signed-off-by: Gaurav Jindal <gauravjindal1104@gmail.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Individual CPUs may have special requirements to not enter
deep idle states. For example, a CPU running real time
applications would not want to enter deep idle states to
avoid latency impacts. At the same time other CPUs that
do not have such a requirement could allow deep idle
states to save power.
This was already implemented in the menu governor.
Implementing similar changes in the ladder governor which
gets selected when CONFIG_NO_HZ and CONFIG_NO_HZ_IDLE are not
set. Refer following commits for the menu governor changes.
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
Ulf Hansson
Linus Torvalds
Johannes Weiner
Daniel Lezcano
Rafael J. Wysocki
Fieah Lim
Akshay Adiga
Sudeep Holla
Gautham R. Shenoy
Marek Szyprowski
Markus Elfring
Nicholas Piggin
gaurav jindal
Vaidyanathan Srinivasan
Ramesh Thomas