Since the cacheinfo LLC information is used directly in arch_topology,
there is no need to parse and store the LLC ID information only for
ACPI systems in the CPU topology.
Remove the redundant LLC ID from the generic CPU arch_topology
information.
Link: https://lore.kernel.org/r/20220704101605.1318280-13-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Define topology_init_cpu_capacity_cppc() to use highest performance
values from _CPC objects to obtain and set maximum capacity information
for each CPU. acpi_cppc_processor_probe() is a good point at which to
trigger the initialization of CPU (u-arch) capacity values, as at this
point the highest performance values can be obtained from each CPU's
_CPC objects. Architectures can therefore use this functionality
through arch_init_invariance_cppc().
The performance scale used by CPPC is a unified scale for all CPUs in
the system. Therefore, by obtaining the raw highest performance values
from the _CPC objects, and normalizing them on the [0, 1024] capacity
scale, used by the task scheduler, we obtain the CPU capacity of each
CPU.
While an ACPI Notify(0x85) could alert about a change in the highest
performance value, which should in turn retrigger the CPU capacity
computations, this notification is not currently handled by the ACPI
processor driver. When supported, a call to arch_init_invariance_cppc()
would perform the update.
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no need of this function (and related) since code has been
converted to use the new arch_update_thermal_pressure() API. The old
code can be removed.
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The thermal pressure is a mechanism which is used for providing
information about reduced CPU performance to the scheduler. Usually code
has to convert the value from frequency units into capacity units,
which are understandable by the scheduler. Create a common conversion code
which can be just used via a handy API.
Internally, the topology_update_thermal_pressure() operates on frequency
in MHz and max CPU frequency is taken from 'freq_factor' (per-cpu).
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Both ACPI and DT provide the ability to describe additional layers of
topology between that of individual cores and higher level constructs
such as the level at which the last level cache is shared.
In ACPI this can be represented in PPTT as a Processor Hierarchy
Node Structure [1] that is the parent of the CPU cores and in turn
has a parent Processor Hierarchy Nodes Structure representing
a higher level of topology.
For example Kunpeng 920 has 6 or 8 clusters in each NUMA node, and each
cluster has 4 cpus. All clusters share L3 cache data, but each cluster
has local L3 tag. On the other hand, each clusters will share some
internal system bus.
+-----------------------------------+ +---------+
| +------+ +------+ +--------------------------+ |
| | CPU0 | | cpu1 | | +-----------+ | |
| +------+ +------+ | | | | |
| +----+ L3 | | |
| +------+ +------+ cluster | | tag | | |
| | CPU2 | | CPU3 | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | |
+-----------------------------------+ | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| | | L3 | | |
| +------+ +------+ +----+ tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | L3 |
| data |
+-----------------------------------+ | |
| +------+ +------+ | +-----------+ | |
| | | | | | | | | |
| +------+ +------+ +----+ L3 | | |
| | | tag | | |
| +------+ +------+ | | | | |
| | | | | | +-----------+ | |
| +------+ +------+ +--------------------------+ |
+-----------------------------------| | |
+-----------------------------------| | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| +----+ L3 | | |
| +------+ +------+ | | tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | |
+-----------------------------------+ | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| | | L3 | | |
| +------+ +------+ +---+ tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | |
+-----------------------------------+ | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| | | L3 | | |
| +------+ +------+ +--+ tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | +---------+
+-----------------------------------+
That means spreading tasks among clusters will bring more bandwidth
while packing tasks within one cluster will lead to smaller cache
synchronization latency. So both kernel and userspace will have
a chance to leverage this topology to deploy tasks accordingly to
achieve either smaller cache latency within one cluster or an even
distribution of load among clusters for higher throughput.
This patch exposes cluster topology to both kernel and userspace.
Libraried like hwloc will know cluster by cluster_cpus and related
sysfs attributes. PoC of HWLOC support at [2].
Note this patch only handle the ACPI case.
Special consideration is needed for SMT processors, where it is
necessary to move 2 levels up the hierarchy from the leaf nodes
(thus skipping the processor core level).
Note that arm64 / ACPI does not provide any means of identifying
a die level in the topology but that may be unrelate to the cluster
level.
[1] ACPI Specification 6.3 - section 5.2.29.1 processor hierarchy node
structure (Type 0)
[2] https://github.com/hisilicon/hwloc/tree/linux-cluster
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210924085104.44806-2-21cnbao@gmail.com
The Frequency Invariance Engine (FIE) is providing a frequency scaling
correction factor that helps achieve more accurate load-tracking.
Normally, this scaling factor can be obtained directly with the help of
the cpufreq drivers as they know the exact frequency the hardware is
running at. But that isn't the case for CPPC cpufreq driver.
Another way of obtaining that is using the arch specific counter
support, which is already present in kernel, but that hardware is
optional for platforms.
This patch updates the CPPC driver to register itself with the topology
core to provide its own implementation (cppc_scale_freq_tick()) of
topology_scale_freq_tick() which gets called by the scheduler on every
tick. Note that the arch specific counters have higher priority than
CPPC counters, if available, though the CPPC driver doesn't need to have
any special handling for that.
On an invocation of cppc_scale_freq_tick(), we schedule an irq work
(since we reach here from hard-irq context), which then schedules a
normal work item and cppc_scale_freq_workfn() updates the per_cpu
arch_freq_scale variable based on the counter updates since the last
tick.
To allow platforms to disable this CPPC counter-based frequency
invariance support, this is all done under CONFIG_ACPI_CPPC_CPUFREQ_FIE,
which is enabled by default.
This also exports sched_setattr_nocheck() as the CPPC driver can be
built as a module.
Cc: linux-acpi@vger.kernel.org
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
This patch attempts to make it generic enough so other parts of the
kernel can also provide their own implementation of scale_freq_tick()
callback, which is called by the scheduler periodically to update the
per-cpu arch_freq_scale variable.
The implementations now need to provide 'struct scale_freq_data' for the
CPUs for which they have hardware counters available, and a callback
gets registered for each possible CPU in a per-cpu variable.
The arch specific (or ARM AMU) counters are updated to adapt to this and
they take the highest priority if they are available, i.e. they will be
used instead of CPPC based counters for example.
The special code to rebuild the sched domains, in case invariance status
change for the system, is moved out of arm64 specific code and is added
to arch_topology.c.
Note that this also defines SCALE_FREQ_SOURCE_CPUFREQ but doesn't use it
and it is added to show that cpufreq is also acts as source of
information for FIE and will be used by default if no other counters are
supported for a platform.
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Will Deacon <will@kernel.org> # for arm64
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Rename freq_scale to a less generic name, as it will get exported soon
for modules. Since x86 already names its own implementation of this as
arch_freq_scale, lets stick to that.
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Compared to other arch_* functions, arch_set_freq_scale() has an atypical
weak definition that can be replaced by a strong architecture specific
implementation.
The more typical support for architectural functions involves defining
an empty stub in a header file if the symbol is not already defined in
architecture code. Some examples involve:
- #define arch_scale_freq_capacity topology_get_freq_scale
- #define arch_scale_freq_invariant topology_scale_freq_invariant
- #define arch_scale_cpu_capacity topology_get_cpu_scale
- #define arch_update_cpu_topology topology_update_cpu_topology
- #define arch_scale_thermal_pressure topology_get_thermal_pressure
- #define arch_set_thermal_pressure topology_set_thermal_pressure
Bring arch_set_freq_scale() in line with these functions by renaming it to
topology_set_freq_scale() in the arch topology driver, and by defining the
arch_set_freq_scale symbol to point to the new function for arm and arm64.
While there are other users of the arch_topology driver, this patch defines
arch_set_freq_scale for arm and arm64 only, due to their existing
definitions of arch_scale_freq_capacity. This is the getter function of the
frequency invariance scale factor and without a getter function, the
setter function - arch_set_freq_scale() has not purpose.
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com> (BL_SWITCHER and topology parts)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
arch_scale_freq_invariant() is used by schedutil to determine whether
the scheduler's load-tracking signals are frequency invariant. Its
definition is overridable, though by default it is hardcoded to 'true'
if arch_scale_freq_capacity() is defined ('false' otherwise).
This behaviour is not overridden on arm, arm64 and other users of the
generic arch topology driver, which is somewhat precarious:
arch_scale_freq_capacity() will always be defined, yet not all cpufreq
drivers are guaranteed to drive the frequency invariance scale factor
setting. In other words, the load-tracking signals may very well *not*
be frequency invariant.
Now that cpufreq can be queried on whether the current driver is driving
the Frequency Invariance (FI) scale setting, the current situation can
be improved. This combines the query of whether cpufreq supports the
setting of the frequency scale factor, with whether all online CPUs are
counter-based FI enabled.
While cpufreq FI enablement applies at system level, for all CPUs,
counter-based FI support could also be used for only a subset of CPUs to
set the invariance scale factor. Therefore, if cpufreq-based FI support
is present, we consider the system to be invariant. If missing, we
require all online CPUs to be counter-based FI enabled in order for the
full system to be considered invariant.
If the system ends up not being invariant, a new condition is needed in
the counter initialization code that disables all scale factor setting
based on counters.
Precedence of counters over cpufreq use is not important here. The
invariant status is only given to the system if all CPUs have at least
one method of setting the frequency scale factor.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The passed cpumask arguments to arch_set_freq_scale() and
arch_freq_counters_available() are only iterated over, so reflect this
in the prototype. This also allows to pass system cpumasks like
cpu_online_mask without getting a warning.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The following commit:
14533a16c4 ("thermal/cpu-cooling, sched/core: Move the arch_set_thermal_pressure() API to generic scheduler code")
moved the definition of arch_set_thermal_pressure() to sched/core.c, but
kept its declaration in linux/arch_topology.h. When building e.g. an x86
kernel with CONFIG_SCHED_THERMAL_PRESSURE=y, cpufreq_cooling.c ends up
getting the declaration of arch_set_thermal_pressure() from
include/linux/arch_topology.h, which is somewhat awkward.
On top of this, sched/core.c unconditionally defines
o The thermal_pressure percpu variable
o arch_set_thermal_pressure()
while arch_scale_thermal_pressure() does nothing unless redefined by the
architecture.
arch_*() functions are meant to be defined by architectures, so revert the
aforementioned commit and re-implement it in a way that keeps
arch_set_thermal_pressure() architecture-definable, and doesn't define the
thermal pressure percpu variable for kernels that don't need
it (CONFIG_SCHED_THERMAL_PRESSURE=n).
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200712165917.9168-2-valentin.schneider@arm.com
- In-kernel Pointer Authentication support (previously only offered to
user space).
- ARM Activity Monitors (AMU) extension support allowing better CPU
utilisation numbers for the scheduler (frequency invariance).
- Memory hot-remove support for arm64.
- Lots of asm annotations (SYM_*) in preparation for the in-kernel
Branch Target Identification (BTI) support.
- arm64 perf updates: ARMv8.5-PMU 64-bit counters, refactoring the PMU
init callbacks, support for new DT compatibles.
- IPv6 header checksum optimisation.
- Fixes: SDEI (software delegated exception interface) double-lock on
hibernate with shared events.
- Minor clean-ups and refactoring: cpu_ops accessor, cpu_do_switch_mm()
converted to C, cpufeature finalisation helper.
- sys_mremap() comment explaining the asymmetric address untagging
behaviour.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
"The bulk is in-kernel pointer authentication, activity monitors and
lots of asm symbol annotations. I also queued the sys_mremap() patch
commenting the asymmetry in the address untagging.
Summary:
- In-kernel Pointer Authentication support (previously only offered
to user space).
- ARM Activity Monitors (AMU) extension support allowing better CPU
utilisation numbers for the scheduler (frequency invariance).
- Memory hot-remove support for arm64.
- Lots of asm annotations (SYM_*) in preparation for the in-kernel
Branch Target Identification (BTI) support.
- arm64 perf updates: ARMv8.5-PMU 64-bit counters, refactoring the
PMU init callbacks, support for new DT compatibles.
- IPv6 header checksum optimisation.
- Fixes: SDEI (software delegated exception interface) double-lock on
hibernate with shared events.
- Minor clean-ups and refactoring: cpu_ops accessor,
cpu_do_switch_mm() converted to C, cpufeature finalisation helper.
- sys_mremap() comment explaining the asymmetric address untagging
behaviour"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits)
mm/mremap: Add comment explaining the untagging behaviour of mremap()
arm64: head: Convert install_el2_stub to SYM_INNER_LABEL
arm64: Introduce get_cpu_ops() helper function
arm64: Rename cpu_read_ops() to init_cpu_ops()
arm64: Declare ACPI parking protocol CPU operation if needed
arm64: move kimage_vaddr to .rodata
arm64: use mov_q instead of literal ldr
arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH
lkdtm: arm64: test kernel pointer authentication
arm64: compile the kernel with ptrauth return address signing
kconfig: Add support for 'as-option'
arm64: suspend: restore the kernel ptrauth keys
arm64: __show_regs: strip PAC from lr in printk
arm64: unwind: strip PAC from kernel addresses
arm64: mask PAC bits of __builtin_return_address
arm64: initialize ptrauth keys for kernel booting task
arm64: initialize and switch ptrauth kernel keys
arm64: enable ptrauth earlier
arm64: cpufeature: handle conflicts based on capability
arm64: cpufeature: Move cpu capability helpers inside C file
...
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle are:
- Various NUMA scheduling updates: harmonize the load-balancer and
NUMA placement logic to not work against each other. The intended
result is better locality, better utilization and fewer migrations.
- Introduce Thermal Pressure tracking and optimizations, to improve
task placement on thermally overloaded systems.
- Implement frequency invariant scheduler accounting on (some) x86
CPUs. This is done by observing and sampling the 'recent' CPU
frequency average at ~tick boundaries. The CPU provides this data
via the APERF/MPERF MSRs. This hopefully makes our capacity
estimates more precise and keeps tasks on the same CPU better even
if it might seem overloaded at a lower momentary frequency. (As
usual, turbo mode is a complication that we resolve by observing
the maximum frequency and renormalizing to it.)
- Add asymmetric CPU capacity wakeup scan to improve capacity
utilization on asymmetric topologies. (big.LITTLE systems)
- PSI fixes and optimizations.
- RT scheduling capacity awareness fixes & improvements.
- Optimize the CONFIG_RT_GROUP_SCHED constraints code.
- Misc fixes, cleanups and optimizations - see the changelog for
details"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits)
threads: Update PID limit comment according to futex UAPI change
sched/fair: Fix condition of avg_load calculation
sched/rt: cpupri_find: Trigger a full search as fallback
kthread: Do not preempt current task if it is going to call schedule()
sched/fair: Improve spreading of utilization
sched: Avoid scale real weight down to zero
psi: Move PF_MEMSTALL out of task->flags
MAINTAINERS: Add maintenance information for psi
psi: Optimize switching tasks inside shared cgroups
psi: Fix cpu.pressure for cpu.max and competing cgroups
sched/core: Distribute tasks within affinity masks
sched/fair: Fix enqueue_task_fair warning
thermal/cpu-cooling, sched/core: Move the arch_set_thermal_pressure() API to generic scheduler code
sched/rt: Remove unnecessary push for unfit tasks
sched/rt: Allow pulling unfitting task
sched/rt: Optimize cpupri_find() on non-heterogenous systems
sched/rt: Re-instate old behavior in select_task_rq_rt()
sched/rt: cpupri_find: Implement fallback mechanism for !fit case
sched/fair: Fix reordering of enqueue/dequeue_task_fair()
sched/fair: Fix runnable_avg for throttled cfs
...
The Frequency Invariance Engine (FIE) is providing a frequency
scaling correction factor that helps achieve more accurate
load-tracking.
So far, for arm and arm64 platforms, this scale factor has been
obtained based on the ratio between the current frequency and the
maximum supported frequency recorded by the cpufreq policy. The
setting of this scale factor is triggered from cpufreq drivers by
calling arch_set_freq_scale. The current frequency used in computation
is the frequency requested by a governor, but it may not be the
frequency that was implemented by the platform.
This correction factor can also be obtained using a core counter and a
constant counter to get information on the performance (frequency based
only) obtained in a period of time. This will more accurately reflect
the actual current frequency of the CPU, compared with the alternative
implementation that reflects the request of a performance level from
the OS.
Therefore, implement arch_scale_freq_tick to use activity monitors, if
present, for the computation of the frequency scale factor.
The use of AMU counters depends on:
- CONFIG_ARM64_AMU_EXTN - depents on the AMU extension being present
- CONFIG_CPU_FREQ - the current frequency obtained using counter
information is divided by the maximum frequency obtained from the
cpufreq policy.
While it is possible to have a combination of CPUs in the system with
and without support for activity monitors, the use of counters for
frequency invariance is only enabled for a CPU if all related CPUs
(CPUs in the same frequency domain) support and have enabled the core
and constant activity monitor counters. In this way, there is a clear
separation between the policies for which arch_set_freq_scale (cpufreq
based FIE) is used, and the policies for which arch_scale_freq_tick
(counter based FIE) is used to set the frequency scale factor. For
this purpose, a late_initcall_sync is registered to trigger validation
work for policies that will enable or disable the use of AMU counters
for frequency invariance. If CONFIG_CPU_FREQ is not defined, the use
of counters is enabled on all CPUs only if all possible CPUs correctly
support the necessary counters.
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add architecture specific APIs to update and track thermal pressure on a
per CPU basis. A per CPU variable thermal_pressure is introduced to keep
track of instantaneous per CPU thermal pressure. Thermal pressure is the
delta between maximum capacity and capped capacity due to a thermal event.
topology_get_thermal_pressure can be hooked into the scheduler specified
arch_scale_thermal_pressure to retrieve instantaneous thermal pressure of
a CPU.
arch_set_thermal_pressure can be used to update the thermal pressure.
Considering topology_get_thermal_pressure reads thermal_pressure and
arch_set_thermal_pressure writes into thermal_pressure, one can argue for
some sort of locking mechanism to avoid a stale value. But considering
topology_get_thermal_pressure can be called from a system critical path
like scheduler tick function, a locking mechanism is not ideal. This means
that it is possible the thermal_pressure value used to calculate average
thermal pressure for a CPU can be stale for up to 1 tick period.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-4-thara.gopinath@linaro.org
The storage class and inline definition as well as the return type,
function name and parameter list fit all into one line.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20200211181515.32570-3-dietmar.eggemann@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The sched domain pointer argument from topology_get_freq_scale() and
topology_get_cpu_scale() got removed by commit 7673c8a4c7
("sched/cpufreq: Remove arch_scale_freq_capacity()'s 'sd' parameter")
and commit 8ec59c0f5f ("sched/topology: Remove unused 'sd' parameter
from arch_scale_cpu_capacity()").
So the 'struct sched_domain' forward declaration is no longer needed.
Remove it.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20200211181515.32570-2-dietmar.eggemann@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The parse_acpi_topology() is not declared anywhere which
causes the following sparse warning:
drivers/base/arch_topology.c:522:19: warning: symbol 'parse_acpi_topology' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20191022084323.13594-1-ben.dooks@codethink.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, ARM32 and ARM64 uses different data structures to represent
their cpu topologies. Since, we are moving the ARM64 topology to common
code to be used by other architectures, we can reuse that for ARM32 as
well.
Take this opprtunity to remove the redundant functions from ARM32 and
reuse the common code instead.
To: Russell King <linux@armlinux.org.uk>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com> (on TC2)
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Both RISC-V & ARM64 are using cpu-map device tree to describe
their cpu topology. It's better to move the relevant code to
a common place instead of duplicate code.
To: Will Deacon <will.deacon@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
[Tested on QDF2400]
Tested-by: Jeffrey Hugo <jhugo@codeaurora.org>
[Tested on Juno and other embedded platforms.]
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
The setting of SD_ASYM_CPUCAPACITY depends on the per-CPU capacities.
These might not have their final values when the hierarchy is initially
built as the values depend on cpufreq to be initialized or the values
being set through sysfs. To ensure that the flags are set correctly we
need to rebuild the sched_domain hierarchy whenever the reported per-CPU
capacity (arch_scale_cpu_capacity()) changes.
This patch ensure that a full sched_domain rebuild happens when CPU
capacity changes occur.
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Link: http://lkml.kernel.org/r/1532093554-30504-3-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
* pm-cpufreq: (22 commits)
cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE
cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const
cpufreq: arm_big_little: make function arguments and structure pointer const
cpufreq: pxa: convert to clock API
cpufreq: speedstep-lib: mark expected switch fall-through
cpufreq: ti-cpufreq: add missing of_node_put()
cpufreq: dt: Remove support for Exynos4212 SoCs
cpufreq: imx6q: Move speed grading check to cpufreq driver
cpufreq: ti-cpufreq: kfree opp_data when failure
cpufreq: SPEAr: pr_err() strings should end with newlines
cpufreq: powernow-k8: pr_err() strings should end with newlines
cpufreq: dt-platdev: drop socionext,uniphier-ld6b from whitelist
arm64: wire cpu-invariant accounting support up to the task scheduler
arm64: wire frequency-invariant accounting support up to the task scheduler
arm: wire cpu-invariant accounting support up to the task scheduler
arm: wire frequency-invariant accounting support up to the task scheduler
drivers base/arch_topology: allow inlining cpu-invariant accounting support
drivers base/arch_topology: provide frequency-invariant accounting support
cpufreq: dt: invoke frequency-invariance setter function
cpufreq: arm_big_little: invoke frequency-invariance setter function
...
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allow inlining of topology_get_cpu_scale() into the task
scheduler fast path (e.g. __update_load_avg_se()) by coding it as a
static inline function in the arch topology header file.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Implements the arch-specific (arm and arm64) frequency-invariance setter
function arch_set_freq_scale() which provides the following frequency
scaling factor:
current_freq(cpu) << SCHED_CAPACITY_SHIFT / max_supported_freq(cpu)
One possible consumer of the frequency-invariance getter function
topology_get_freq_scale() is the Per-Entity Load Tracking (PELT)
mechanism of the task scheduler.
Allow inlining of topology_get_freq_scale() into the task scheduler
fast path (e.g. __update_load_avg_se()) by coding it as a static inline
function in the arch topology header file.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
topology_parse_cpu_capacity() returns 1 on success and 0 on errors. Make
it return bool instead of int as that suits the purpose better.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that some functions that deal with arch topology information live
under drivers, there is a clash of naming that might create confusion.
Tidy things up by creating a topology namespace for interfaces used by
arch code; achieve this by prepending a 'topology_' prefix to driver
interfaces.
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Create a new header file (include/linux/arch_topology.h) and put there
declarations of interfaces used by arm, arm64 and drivers code.
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sudeep Holla