mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-24 12:44:11 +08:00
The main changes in this cycle were:
- Improve uclamp performance by using a static key for the fast path
- Add the "sched_util_clamp_min_rt_default" sysctl, to optimize for
better power efficiency of RT tasks on battery powered devices.
(The default is to maximize performance & reduce RT latencies.)
- Improve utime and stime tracking accuracy, which had a fixed boundary
of error, which created larger and larger relative errors as the values
become larger. This is now replaced with more precise arithmetics,
using the new mul_u64_u64_div_u64() helper in math64.h.
- Improve the deadline scheduler, such as making it capacity aware
- Improve frequency-invariant scheduling
- Misc cleanups in energy/power aware scheduling
- Add sched_update_nr_running tracepoint to track changes to nr_running
- Documentation additions and updates
- Misc cleanups and smaller fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
- Improve uclamp performance by using a static key for the fast path
- Add the "sched_util_clamp_min_rt_default" sysctl, to optimize for
better power efficiency of RT tasks on battery powered devices.
(The default is to maximize performance & reduce RT latencies.)
- Improve utime and stime tracking accuracy, which had a fixed boundary
of error, which created larger and larger relative errors as the
values become larger. This is now replaced with more precise
arithmetics, using the new mul_u64_u64_div_u64() helper in math64.h.
- Improve the deadline scheduler, such as making it capacity aware
- Improve frequency-invariant scheduling
- Misc cleanups in energy/power aware scheduling
- Add sched_update_nr_running tracepoint to track changes to nr_running
- Documentation additions and updates
- Misc cleanups and smaller fixes
* tag 'sched-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
sched/doc: Factorize bits between sched-energy.rst & sched-capacity.rst
sched/doc: Document capacity aware scheduling
sched: Document arch_scale_*_capacity()
arm, arm64: Fix selection of CONFIG_SCHED_THERMAL_PRESSURE
Documentation/sysctl: Document uclamp sysctl knobs
sched/uclamp: Add a new sysctl to control RT default boost value
sched/uclamp: Fix a deadlock when enabling uclamp static key
sched: Remove duplicated tick_nohz_full_enabled() check
sched: Fix a typo in a comment
sched/uclamp: Remove unnecessary mutex_init()
arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE
sched: Cleanup SCHED_THERMAL_PRESSURE kconfig entry
arch_topology, sched/core: Cleanup thermal pressure definition
trace/events/sched.h: fix duplicated word
linux/sched/mm.h: drop duplicated words in comments
smp: Fix a potential usage of stale nr_cpus
sched/fair: update_pick_idlest() Select group with lowest group_util when idle_cpus are equal
sched: nohz: stop passing around unused "ticks" parameter.
sched: Better document ttwu()
sched: Add a tracepoint to track rq->nr_running
...
This commit is contained in:
Linus Torvalds
commit
e4cbce4d13
@ -1062,6 +1062,60 @@ Enables/disables scheduler statistics. Enabling this feature
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incurs a small amount of overhead in the scheduler but is
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useful for debugging and performance tuning.
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sched_util_clamp_min:
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=====================
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Max allowed *minimum* utilization.
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Default value is 1024, which is the maximum possible value.
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It means that any requested uclamp.min value cannot be greater than
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sched_util_clamp_min, i.e., it is restricted to the range
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[0:sched_util_clamp_min].
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sched_util_clamp_max:
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=====================
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Max allowed *maximum* utilization.
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Default value is 1024, which is the maximum possible value.
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It means that any requested uclamp.max value cannot be greater than
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sched_util_clamp_max, i.e., it is restricted to the range
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[0:sched_util_clamp_max].
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sched_util_clamp_min_rt_default:
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================================
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By default Linux is tuned for performance. Which means that RT tasks always run
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at the highest frequency and most capable (highest capacity) CPU (in
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heterogeneous systems).
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Uclamp achieves this by setting the requested uclamp.min of all RT tasks to
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1024 by default, which effectively boosts the tasks to run at the highest
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frequency and biases them to run on the biggest CPU.
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This knob allows admins to change the default behavior when uclamp is being
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used. In battery powered devices particularly, running at the maximum
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capacity and frequency will increase energy consumption and shorten the battery
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life.
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This knob is only effective for RT tasks which the user hasn't modified their
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requested uclamp.min value via sched_setattr() syscall.
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This knob will not escape the range constraint imposed by sched_util_clamp_min
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defined above.
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For example if
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sched_util_clamp_min_rt_default = 800
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sched_util_clamp_min = 600
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Then the boost will be clamped to 600 because 800 is outside of the permissible
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range of [0:600]. This could happen for instance if a powersave mode will
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restrict all boosts temporarily by modifying sched_util_clamp_min. As soon as
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this restriction is lifted, the requested sched_util_clamp_min_rt_default
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will take effect.
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seccomp
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=======
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@ -12,6 +12,7 @@ Linux Scheduler
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sched-deadline
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sched-design-CFS
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sched-domains
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sched-capacity
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sched-energy
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sched-nice-design
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sched-rt-group
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439
Documentation/scheduler/sched-capacity.rst
Normal file
439
Documentation/scheduler/sched-capacity.rst
Normal file
@ -0,0 +1,439 @@
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=========================
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Capacity Aware Scheduling
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=========================
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1. CPU Capacity
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===============
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1.1 Introduction
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----------------
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Conventional, homogeneous SMP platforms are composed of purely identical
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CPUs. Heterogeneous platforms on the other hand are composed of CPUs with
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different performance characteristics - on such platforms, not all CPUs can be
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considered equal.
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CPU capacity is a measure of the performance a CPU can reach, normalized against
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the most performant CPU in the system. Heterogeneous systems are also called
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asymmetric CPU capacity systems, as they contain CPUs of different capacities.
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Disparity in maximum attainable performance (IOW in maximum CPU capacity) stems
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from two factors:
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- not all CPUs may have the same microarchitecture (µarch).
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- with Dynamic Voltage and Frequency Scaling (DVFS), not all CPUs may be
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physically able to attain the higher Operating Performance Points (OPP).
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Arm big.LITTLE systems are an example of both. The big CPUs are more
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performance-oriented than the LITTLE ones (more pipeline stages, bigger caches,
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smarter predictors, etc), and can usually reach higher OPPs than the LITTLE ones
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can.
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CPU performance is usually expressed in Millions of Instructions Per Second
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(MIPS), which can also be expressed as a given amount of instructions attainable
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per Hz, leading to::
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capacity(cpu) = work_per_hz(cpu) * max_freq(cpu)
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1.2 Scheduler terms
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-------------------
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Two different capacity values are used within the scheduler. A CPU's
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``capacity_orig`` is its maximum attainable capacity, i.e. its maximum
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attainable performance level. A CPU's ``capacity`` is its ``capacity_orig`` to
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which some loss of available performance (e.g. time spent handling IRQs) is
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subtracted.
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Note that a CPU's ``capacity`` is solely intended to be used by the CFS class,
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while ``capacity_orig`` is class-agnostic. The rest of this document will use
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the term ``capacity`` interchangeably with ``capacity_orig`` for the sake of
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brevity.
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1.3 Platform examples
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---------------------
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1.3.1 Identical OPPs
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~~~~~~~~~~~~~~~~~~~~
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Consider an hypothetical dual-core asymmetric CPU capacity system where
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- work_per_hz(CPU0) = W
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- work_per_hz(CPU1) = W/2
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- all CPUs are running at the same fixed frequency
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By the above definition of capacity:
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- capacity(CPU0) = C
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- capacity(CPU1) = C/2
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To draw the parallel with Arm big.LITTLE, CPU0 would be a big while CPU1 would
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be a LITTLE.
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With a workload that periodically does a fixed amount of work, you will get an
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execution trace like so::
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CPU0 work ^
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| ____ ____ ____
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| | | | | | |
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+----+----+----+----+----+----+----+----+----+----+-> time
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CPU1 work ^
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| _________ _________ ____
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| | | | | |
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+----+----+----+----+----+----+----+----+----+----+-> time
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CPU0 has the highest capacity in the system (C), and completes a fixed amount of
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work W in T units of time. On the other hand, CPU1 has half the capacity of
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CPU0, and thus only completes W/2 in T.
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1.3.2 Different max OPPs
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~~~~~~~~~~~~~~~~~~~~~~~~
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Usually, CPUs of different capacity values also have different maximum
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OPPs. Consider the same CPUs as above (i.e. same work_per_hz()) with:
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- max_freq(CPU0) = F
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- max_freq(CPU1) = 2/3 * F
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This yields:
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- capacity(CPU0) = C
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- capacity(CPU1) = C/3
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Executing the same workload as described in 1.3.1, which each CPU running at its
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maximum frequency results in::
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CPU0 work ^
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| ____ ____ ____
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| | | | | | |
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+----+----+----+----+----+----+----+----+----+----+-> time
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workload on CPU1
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CPU1 work ^
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| ______________ ______________ ____
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| | | | | |
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+----+----+----+----+----+----+----+----+----+----+-> time
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||||
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1.4 Representation caveat
|
||||
-------------------------
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It should be noted that having a *single* value to represent differences in CPU
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performance is somewhat of a contentious point. The relative performance
|
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difference between two different µarchs could be X% on integer operations, Y% on
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floating point operations, Z% on branches, and so on. Still, results using this
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simple approach have been satisfactory for now.
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2. Task utilization
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||||
===================
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2.1 Introduction
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||||
----------------
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||||
|
||||
Capacity aware scheduling requires an expression of a task's requirements with
|
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regards to CPU capacity. Each scheduler class can express this differently, and
|
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while task utilization is specific to CFS, it is convenient to describe it here
|
||||
in order to introduce more generic concepts.
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|
||||
Task utilization is a percentage meant to represent the throughput requirements
|
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of a task. A simple approximation of it is the task's duty cycle, i.e.::
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task_util(p) = duty_cycle(p)
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On an SMP system with fixed frequencies, 100% utilization suggests the task is a
|
||||
busy loop. Conversely, 10% utilization hints it is a small periodic task that
|
||||
spends more time sleeping than executing. Variable CPU frequencies and
|
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asymmetric CPU capacities complexify this somewhat; the following sections will
|
||||
expand on these.
|
||||
|
||||
2.2 Frequency invariance
|
||||
------------------------
|
||||
|
||||
One issue that needs to be taken into account is that a workload's duty cycle is
|
||||
directly impacted by the current OPP the CPU is running at. Consider running a
|
||||
periodic workload at a given frequency F::
|
||||
|
||||
CPU work ^
|
||||
| ____ ____ ____
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||||
| | | | | | |
|
||||
+----+----+----+----+----+----+----+----+----+----+-> time
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||||
|
||||
This yields duty_cycle(p) == 25%.
|
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|
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Now, consider running the *same* workload at frequency F/2::
|
||||
|
||||
CPU work ^
|
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| _________ _________ ____
|
||||
| | | | | |
|
||||
+----+----+----+----+----+----+----+----+----+----+-> time
|
||||
|
||||
This yields duty_cycle(p) == 50%, despite the task having the exact same
|
||||
behaviour (i.e. executing the same amount of work) in both executions.
|
||||
|
||||
The task utilization signal can be made frequency invariant using the following
|
||||
formula::
|
||||
|
||||
task_util_freq_inv(p) = duty_cycle(p) * (curr_frequency(cpu) / max_frequency(cpu))
|
||||
|
||||
Applying this formula to the two examples above yields a frequency invariant
|
||||
task utilization of 25%.
|
||||
|
||||
2.3 CPU invariance
|
||||
------------------
|
||||
|
||||
CPU capacity has a similar effect on task utilization in that running an
|
||||
identical workload on CPUs of different capacity values will yield different
|
||||
duty cycles.
|
||||
|
||||
Consider the system described in 1.3.2., i.e.::
|
||||
|
||||
- capacity(CPU0) = C
|
||||
- capacity(CPU1) = C/3
|
||||
|
||||
Executing a given periodic workload on each CPU at their maximum frequency would
|
||||
result in::
|
||||
|
||||
CPU0 work ^
|
||||
| ____ ____ ____
|
||||
| | | | | | |
|
||||
+----+----+----+----+----+----+----+----+----+----+-> time
|
||||
|
||||
CPU1 work ^
|
||||
| ______________ ______________ ____
|
||||
| | | | | |
|
||||
+----+----+----+----+----+----+----+----+----+----+-> time
|
||||
|
||||
IOW,
|
||||
|
||||
- duty_cycle(p) == 25% if p runs on CPU0 at its maximum frequency
|
||||
- duty_cycle(p) == 75% if p runs on CPU1 at its maximum frequency
|
||||
|
||||
The task utilization signal can be made CPU invariant using the following
|
||||
formula::
|
||||
|
||||
task_util_cpu_inv(p) = duty_cycle(p) * (capacity(cpu) / max_capacity)
|
||||
|
||||
with ``max_capacity`` being the highest CPU capacity value in the
|
||||
system. Applying this formula to the above example above yields a CPU
|
||||
invariant task utilization of 25%.
|
||||
|
||||
2.4 Invariant task utilization
|
||||
------------------------------
|
||||
|
||||
Both frequency and CPU invariance need to be applied to task utilization in
|
||||
order to obtain a truly invariant signal. The pseudo-formula for a task
|
||||
utilization that is both CPU and frequency invariant is thus, for a given
|
||||
task p::
|
||||
|
||||
curr_frequency(cpu) capacity(cpu)
|
||||
task_util_inv(p) = duty_cycle(p) * ------------------- * -------------
|
||||
max_frequency(cpu) max_capacity
|
||||
|
||||
In other words, invariant task utilization describes the behaviour of a task as
|
||||
if it were running on the highest-capacity CPU in the system, running at its
|
||||
maximum frequency.
|
||||
|
||||
Any mention of task utilization in the following sections will imply its
|
||||
invariant form.
|
||||
|
||||
2.5 Utilization estimation
|
||||
--------------------------
|
||||
|
||||
Without a crystal ball, task behaviour (and thus task utilization) cannot
|
||||
accurately be predicted the moment a task first becomes runnable. The CFS class
|
||||
maintains a handful of CPU and task signals based on the Per-Entity Load
|
||||
Tracking (PELT) mechanism, one of those yielding an *average* utilization (as
|
||||
opposed to instantaneous).
|
||||
|
||||
This means that while the capacity aware scheduling criteria will be written
|
||||
considering a "true" task utilization (using a crystal ball), the implementation
|
||||
will only ever be able to use an estimator thereof.
|
||||
|
||||
3. Capacity aware scheduling requirements
|
||||
=========================================
|
||||
|
||||
3.1 CPU capacity
|
||||
----------------
|
||||
|
||||
Linux cannot currently figure out CPU capacity on its own, this information thus
|
||||
needs to be handed to it. Architectures must define arch_scale_cpu_capacity()
|
||||
for that purpose.
|
||||
|
||||
The arm and arm64 architectures directly map this to the arch_topology driver
|
||||
CPU scaling data, which is derived from the capacity-dmips-mhz CPU binding; see
|
||||
Documentation/devicetree/bindings/arm/cpu-capacity.txt.
|
||||
|
||||
3.2 Frequency invariance
|
||||
------------------------
|
||||
|
||||
As stated in 2.2, capacity-aware scheduling requires a frequency-invariant task
|
||||
utilization. Architectures must define arch_scale_freq_capacity(cpu) for that
|
||||
purpose.
|
||||
|
||||
Implementing this function requires figuring out at which frequency each CPU
|
||||
have been running at. One way to implement this is to leverage hardware counters
|
||||
whose increment rate scale with a CPU's current frequency (APERF/MPERF on x86,
|
||||
AMU on arm64). Another is to directly hook into cpufreq frequency transitions,
|
||||
when the kernel is aware of the switched-to frequency (also employed by
|
||||
arm/arm64).
|
||||
|
||||
4. Scheduler topology
|
||||
=====================
|
||||
|
||||
During the construction of the sched domains, the scheduler will figure out
|
||||
whether the system exhibits asymmetric CPU capacities. Should that be the
|
||||
case:
|
||||
|
||||
- The sched_asym_cpucapacity static key will be enabled.
|
||||
- The SD_ASYM_CPUCAPACITY flag will be set at the lowest sched_domain level that
|
||||
spans all unique CPU capacity values.
|
||||
|
||||
The sched_asym_cpucapacity static key is intended to guard sections of code that
|
||||
cater to asymmetric CPU capacity systems. Do note however that said key is
|
||||
*system-wide*. Imagine the following setup using cpusets::
|
||||
|
||||
capacity C/2 C
|
||||
________ ________
|
||||
/ \ / \
|
||||
CPUs 0 1 2 3 4 5 6 7
|
||||
\__/ \______________/
|
||||
cpusets cs0 cs1
|
||||
|
||||
Which could be created via:
|
||||
|
||||
.. code-block:: sh
|
||||
|
||||
mkdir /sys/fs/cgroup/cpuset/cs0
|
||||
echo 0-1 > /sys/fs/cgroup/cpuset/cs0/cpuset.cpus
|
||||
echo 0 > /sys/fs/cgroup/cpuset/cs0/cpuset.mems
|
||||
|
||||
mkdir /sys/fs/cgroup/cpuset/cs1
|
||||
echo 2-7 > /sys/fs/cgroup/cpuset/cs1/cpuset.cpus
|
||||
echo 0 > /sys/fs/cgroup/cpuset/cs1/cpuset.mems
|
||||
|
||||
echo 0 > /sys/fs/cgroup/cpuset/cpuset.sched_load_balance
|
||||
|
||||
Since there *is* CPU capacity asymmetry in the system, the
|
||||
sched_asym_cpucapacity static key will be enabled. However, the sched_domain
|
||||
hierarchy of CPUs 0-1 spans a single capacity value: SD_ASYM_CPUCAPACITY isn't
|
||||
set in that hierarchy, it describes an SMP island and should be treated as such.
|
||||
|
||||
Therefore, the 'canonical' pattern for protecting codepaths that cater to
|
||||
asymmetric CPU capacities is to:
|
||||
|
||||
- Check the sched_asym_cpucapacity static key
|
||||
- If it is enabled, then also check for the presence of SD_ASYM_CPUCAPACITY in
|
||||
the sched_domain hierarchy (if relevant, i.e. the codepath targets a specific
|
||||
CPU or group thereof)
|
||||
|
||||
5. Capacity aware scheduling implementation
|
||||
===========================================
|
||||
|
||||
5.1 CFS
|
||||
-------
|
||||
|
||||
5.1.1 Capacity fitness
|
||||
~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
The main capacity scheduling criterion of CFS is::
|
||||
|
||||
task_util(p) < capacity(task_cpu(p))
|
||||
|
||||
This is commonly called the capacity fitness criterion, i.e. CFS must ensure a
|
||||
task "fits" on its CPU. If it is violated, the task will need to achieve more
|
||||
work than what its CPU can provide: it will be CPU-bound.
|
||||
|
||||
Furthermore, uclamp lets userspace specify a minimum and a maximum utilization
|
||||
value for a task, either via sched_setattr() or via the cgroup interface (see
|
||||
Documentation/admin-guide/cgroup-v2.rst). As its name imply, this can be used to
|
||||
clamp task_util() in the previous criterion.
|
||||
|
||||
5.1.2 Wakeup CPU selection
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
CFS task wakeup CPU selection follows the capacity fitness criterion described
|
||||
above. On top of that, uclamp is used to clamp the task utilization values,
|
||||
which lets userspace have more leverage over the CPU selection of CFS
|
||||
tasks. IOW, CFS wakeup CPU selection searches for a CPU that satisfies::
|
||||
|
||||
clamp(task_util(p), task_uclamp_min(p), task_uclamp_max(p)) < capacity(cpu)
|
||||
|
||||
By using uclamp, userspace can e.g. allow a busy loop (100% utilization) to run
|
||||
on any CPU by giving it a low uclamp.max value. Conversely, it can force a small
|
||||
periodic task (e.g. 10% utilization) to run on the highest-performance CPUs by
|
||||
giving it a high uclamp.min value.
|
||||
|
||||
.. note::
|
||||
|
||||
Wakeup CPU selection in CFS can be eclipsed by Energy Aware Scheduling
|
||||
(EAS), which is described in Documentation/scheduling/sched-energy.rst.
|
||||
|
||||
5.1.3 Load balancing
|
||||
~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
A pathological case in the wakeup CPU selection occurs when a task rarely
|
||||
sleeps, if at all - it thus rarely wakes up, if at all. Consider::
|
||||
|
||||
w == wakeup event
|
||||
|
||||
capacity(CPU0) = C
|
||||
capacity(CPU1) = C / 3
|
||||
|
||||
workload on CPU0
|
||||
CPU work ^
|
||||
| _________ _________ ____
|
||||
| | | | | |
|
||||
+----+----+----+----+----+----+----+----+----+----+-> time
|
||||
w w w
|
||||
|
||||
workload on CPU1
|
||||
CPU work ^
|
||||
| ____________________________________________
|
||||
| |
|
||||
+----+----+----+----+----+----+----+----+----+----+->
|
||||
w
|
||||
|
||||
This workload should run on CPU0, but if the task either:
|
||||
|
||||
- was improperly scheduled from the start (inaccurate initial
|
||||
utilization estimation)
|
||||
- was properly scheduled from the start, but suddenly needs more
|
||||
processing power
|
||||
|
||||
then it might become CPU-bound, IOW ``task_util(p) > capacity(task_cpu(p))``;
|
||||
the CPU capacity scheduling criterion is violated, and there may not be any more
|
||||
wakeup event to fix this up via wakeup CPU selection.
|
||||
|
||||
Tasks that are in this situation are dubbed "misfit" tasks, and the mechanism
|
||||
put in place to handle this shares the same name. Misfit task migration
|
||||
leverages the CFS load balancer, more specifically the active load balance part
|
||||
(which caters to migrating currently running tasks). When load balance happens,
|
||||
a misfit active load balance will be triggered if a misfit task can be migrated
|
||||
to a CPU with more capacity than its current one.
|
||||
|
||||
5.2 RT
|
||||
------
|
||||
|
||||
5.2.1 Wakeup CPU selection
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
RT task wakeup CPU selection searches for a CPU that satisfies::
|
||||
|
||||
task_uclamp_min(p) <= capacity(task_cpu(cpu))
|
||||
|
||||
while still following the usual priority constraints. If none of the candidate
|
||||
CPUs can satisfy this capacity criterion, then strict priority based scheduling
|
||||
is followed and CPU capacities are ignored.
|
||||
|
||||
5.3 DL
|
||||
------
|
||||
|
||||
5.3.1 Wakeup CPU selection
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
DL task wakeup CPU selection searches for a CPU that satisfies::
|
||||
|
||||
task_bandwidth(p) < capacity(task_cpu(p))
|
||||
|
||||
while still respecting the usual bandwidth and deadline constraints. If
|
||||
none of the candidate CPUs can satisfy this capacity criterion, then the
|
||||
task will remain on its current CPU.
|
||||
@ -331,16 +331,8 @@ asymmetric CPU topologies for now. This requirement is checked at run-time by
|
||||
looking for the presence of the SD_ASYM_CPUCAPACITY flag when the scheduling
|
||||
domains are built.
|
||||
|
||||
The flag is set/cleared automatically by the scheduler topology code whenever
|
||||
there are CPUs with different capacities in a root domain. The capacities of
|
||||
CPUs are provided by arch-specific code through the arch_scale_cpu_capacity()
|
||||
callback. As an example, arm and arm64 share an implementation of this callback
|
||||
which uses a combination of CPUFreq data and device-tree bindings to compute the
|
||||
capacity of CPUs (see drivers/base/arch_topology.c for more details).
|
||||
|
||||
So, in order to use EAS on your platform your architecture must implement the
|
||||
arch_scale_cpu_capacity() callback, and some of the CPUs must have a lower
|
||||
capacity than others.
|
||||
See Documentation/sched/sched-capacity.rst for requirements to be met for this
|
||||
flag to be set in the sched_domain hierarchy.
|
||||
|
||||
Please note that EAS is not fundamentally incompatible with SMP, but no
|
||||
significant savings on SMP platforms have been observed yet. This restriction
|
||||
|
||||
@ -16,8 +16,9 @@
|
||||
/* Enable topology flag updates */
|
||||
#define arch_update_cpu_topology topology_update_cpu_topology
|
||||
|
||||
/* Replace task scheduler's default thermal pressure retrieve API */
|
||||
/* Replace task scheduler's default thermal pressure API */
|
||||
#define arch_scale_thermal_pressure topology_get_thermal_pressure
|
||||
#define arch_set_thermal_pressure topology_set_thermal_pressure
|
||||
|
||||
#else
|
||||
|
||||
|
||||
@ -34,8 +34,9 @@ void topology_scale_freq_tick(void);
|
||||
/* Enable topology flag updates */
|
||||
#define arch_update_cpu_topology topology_update_cpu_topology
|
||||
|
||||
/* Replace task scheduler's default thermal pressure retrieve API */
|
||||
/* Replace task scheduler's default thermal pressure API */
|
||||
#define arch_scale_thermal_pressure topology_get_thermal_pressure
|
||||
#define arch_set_thermal_pressure topology_set_thermal_pressure
|
||||
|
||||
#include <asm-generic/topology.h>
|
||||
|
||||
|
||||
@ -74,16 +74,26 @@ static inline u64 mul_u32_u32(u32 a, u32 b)
|
||||
#else
|
||||
# include <asm-generic/div64.h>
|
||||
|
||||
static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 div)
|
||||
/*
|
||||
* Will generate an #DE when the result doesn't fit u64, could fix with an
|
||||
* __ex_table[] entry when it becomes an issue.
|
||||
*/
|
||||
static inline u64 mul_u64_u64_div_u64(u64 a, u64 mul, u64 div)
|
||||
{
|
||||
u64 q;
|
||||
|
||||
asm ("mulq %2; divq %3" : "=a" (q)
|
||||
: "a" (a), "rm" ((u64)mul), "rm" ((u64)div)
|
||||
: "a" (a), "rm" (mul), "rm" (div)
|
||||
: "rdx");
|
||||
|
||||
return q;
|
||||
}
|
||||
#define mul_u64_u64_div_u64 mul_u64_u64_div_u64
|
||||
|
||||
static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 div)
|
||||
{
|
||||
return mul_u64_u64_div_u64(a, mul, div);
|
||||
}
|
||||
#define mul_u64_u32_div mul_u64_u32_div
|
||||
|
||||
#endif /* CONFIG_X86_32 */
|
||||
|
||||
@ -193,7 +193,7 @@ static inline void sched_clear_itmt_support(void)
|
||||
}
|
||||
#endif /* CONFIG_SCHED_MC_PRIO */
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
#if defined(CONFIG_SMP) && defined(CONFIG_X86_64)
|
||||
#include <asm/cpufeature.h>
|
||||
|
||||
DECLARE_STATIC_KEY_FALSE(arch_scale_freq_key);
|
||||
|
||||
@ -56,6 +56,7 @@
|
||||
#include <linux/cpuidle.h>
|
||||
#include <linux/numa.h>
|
||||
#include <linux/pgtable.h>
|
||||
#include <linux/overflow.h>
|
||||
|
||||
#include <asm/acpi.h>
|
||||
#include <asm/desc.h>
|
||||
@ -1777,6 +1778,7 @@ void native_play_dead(void)
|
||||
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_X86_64
|
||||
/*
|
||||
* APERF/MPERF frequency ratio computation.
|
||||
*
|
||||
@ -1975,6 +1977,7 @@ static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
|
||||
static bool intel_set_max_freq_ratio(void)
|
||||
{
|
||||
u64 base_freq, turbo_freq;
|
||||
u64 turbo_ratio;
|
||||
|
||||
if (slv_set_max_freq_ratio(&base_freq, &turbo_freq))
|
||||
goto out;
|
||||
@ -2000,15 +2003,23 @@ out:
|
||||
/*
|
||||
* Some hypervisors advertise X86_FEATURE_APERFMPERF
|
||||
* but then fill all MSR's with zeroes.
|
||||
* Some CPUs have turbo boost but don't declare any turbo ratio
|
||||
* in MSR_TURBO_RATIO_LIMIT.
|
||||
*/
|
||||
if (!base_freq) {
|
||||
pr_debug("Couldn't determine cpu base frequency, necessary for scale-invariant accounting.\n");
|
||||
if (!base_freq || !turbo_freq) {
|
||||
pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n");
|
||||
return false;
|
||||
}
|
||||
|
||||
arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE,
|
||||
base_freq);
|
||||
turbo_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq);
|
||||
if (!turbo_ratio) {
|
||||
pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n");
|
||||
return false;
|
||||
}
|
||||
|
||||
arch_turbo_freq_ratio = turbo_ratio;
|
||||
arch_set_max_freq_ratio(turbo_disabled());
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
@ -2048,11 +2059,19 @@ static void init_freq_invariance(bool secondary)
|
||||
}
|
||||
}
|
||||
|
||||
static void disable_freq_invariance_workfn(struct work_struct *work)
|
||||
{
|
||||
static_branch_disable(&arch_scale_freq_key);
|
||||
}
|
||||
|
||||
static DECLARE_WORK(disable_freq_invariance_work,
|
||||
disable_freq_invariance_workfn);
|
||||
|
||||
DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE;
|
||||
|
||||
void arch_scale_freq_tick(void)
|
||||
{
|
||||
u64 freq_scale;
|
||||
u64 freq_scale = SCHED_CAPACITY_SCALE;
|
||||
u64 aperf, mperf;
|
||||
u64 acnt, mcnt;
|
||||
|
||||
@ -2064,19 +2083,32 @@ void arch_scale_freq_tick(void)
|
||||
|
||||
acnt = aperf - this_cpu_read(arch_prev_aperf);
|
||||
mcnt = mperf - this_cpu_read(arch_prev_mperf);
|
||||
if (!mcnt)
|
||||
return;
|
||||
|
||||
this_cpu_write(arch_prev_aperf, aperf);
|
||||
this_cpu_write(arch_prev_mperf, mperf);
|
||||
|
||||
acnt <<= 2*SCHED_CAPACITY_SHIFT;
|
||||
mcnt *= arch_max_freq_ratio;
|
||||
if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt))
|
||||
goto error;
|
||||
|
||||
if (check_mul_overflow(mcnt, arch_max_freq_ratio, &mcnt) || !mcnt)
|
||||
goto error;
|
||||
|
||||
freq_scale = div64_u64(acnt, mcnt);
|
||||
if (!freq_scale)
|
||||
goto error;
|
||||
|
||||
if (freq_scale > SCHED_CAPACITY_SCALE)
|
||||
freq_scale = SCHED_CAPACITY_SCALE;
|
||||
|
||||
this_cpu_write(arch_freq_scale, freq_scale);
|
||||
return;
|
||||
|
||||
error:
|
||||
pr_warn("Scheduler frequency invariance went wobbly, disabling!\n");
|
||||
schedule_work(&disable_freq_invariance_work);
|
||||
}
|
||||
#else
|
||||
static inline void init_freq_invariance(bool secondary)
|
||||
{
|
||||
}
|
||||
#endif /* CONFIG_X86_64 */
|
||||
|
||||
@ -54,6 +54,17 @@ void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
|
||||
per_cpu(cpu_scale, cpu) = capacity;
|
||||
}
|
||||
|
||||
DEFINE_PER_CPU(unsigned long, thermal_pressure);
|
||||
|
||||
void topology_set_thermal_pressure(const struct cpumask *cpus,
|
||||
unsigned long th_pressure)
|
||||
{
|
||||
int cpu;
|
||||
|
||||
for_each_cpu(cpu, cpus)
|
||||
WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);
|
||||
}
|
||||
|
||||
static ssize_t cpu_capacity_show(struct device *dev,
|
||||
struct device_attribute *attr,
|
||||
char *buf)
|
||||
|
||||
@ -12,6 +12,7 @@
|
||||
#include <linux/string.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/sched/isolation.h>
|
||||
#include <linux/cpu.h>
|
||||
#include <linux/pm_runtime.h>
|
||||
#include <linux/suspend.h>
|
||||
@ -333,6 +334,7 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
|
||||
const struct pci_device_id *id)
|
||||
{
|
||||
int error, node, cpu;
|
||||
int hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
|
||||
struct drv_dev_and_id ddi = { drv, dev, id };
|
||||
|
||||
/*
|
||||
@ -353,7 +355,8 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
|
||||
pci_physfn_is_probed(dev))
|
||||
cpu = nr_cpu_ids;
|
||||
else
|
||||
cpu = cpumask_any_and(cpumask_of_node(node), cpu_online_mask);
|
||||
cpu = cpumask_any_and(cpumask_of_node(node),
|
||||
housekeeping_cpumask(hk_flags));
|
||||
|
||||
if (cpu < nr_cpu_ids)
|
||||
error = work_on_cpu(cpu, local_pci_probe, &ddi);
|
||||
|
||||
@ -109,12 +109,31 @@
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Align to a 32 byte boundary equal to the
|
||||
* alignment gcc 4.5 uses for a struct
|
||||
* GCC 4.5 and later have a 32 bytes section alignment for structures.
|
||||
* Except GCC 4.9, that feels the need to align on 64 bytes.
|
||||
*/
|
||||
#if __GNUC__ == 4 && __GNUC_MINOR__ == 9
|
||||
#define STRUCT_ALIGNMENT 64
|
||||
#else
|
||||
#define STRUCT_ALIGNMENT 32
|
||||
#endif
|
||||
#define STRUCT_ALIGN() . = ALIGN(STRUCT_ALIGNMENT)
|
||||
|
||||
/*
|
||||
* The order of the sched class addresses are important, as they are
|
||||
* used to determine the order of the priority of each sched class in
|
||||
* relation to each other.
|
||||
*/
|
||||
#define SCHED_DATA \
|
||||
STRUCT_ALIGN(); \
|
||||
__begin_sched_classes = .; \
|
||||
*(__idle_sched_class) \
|
||||
*(__fair_sched_class) \
|
||||
*(__rt_sched_class) \
|
||||
*(__dl_sched_class) \
|
||||
*(__stop_sched_class) \
|
||||
__end_sched_classes = .;
|
||||
|
||||
/* The actual configuration determine if the init/exit sections
|
||||
* are handled as text/data or they can be discarded (which
|
||||
* often happens at runtime)
|
||||
@ -389,6 +408,7 @@
|
||||
.rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \
|
||||
__start_rodata = .; \
|
||||
*(.rodata) *(.rodata.*) \
|
||||
SCHED_DATA \
|
||||
RO_AFTER_INIT_DATA /* Read only after init */ \
|
||||
. = ALIGN(8); \
|
||||
__start___tracepoints_ptrs = .; \
|
||||
|
||||
@ -39,8 +39,8 @@ static inline unsigned long topology_get_thermal_pressure(int cpu)
|
||||
return per_cpu(thermal_pressure, cpu);
|
||||
}
|
||||
|
||||
void arch_set_thermal_pressure(struct cpumask *cpus,
|
||||
unsigned long th_pressure);
|
||||
void topology_set_thermal_pressure(const struct cpumask *cpus,
|
||||
unsigned long th_pressure);
|
||||
|
||||
struct cpu_topology {
|
||||
int thread_id;
|
||||
|
||||
@ -263,6 +263,8 @@ static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 divisor)
|
||||
}
|
||||
#endif /* mul_u64_u32_div */
|
||||
|
||||
u64 mul_u64_u64_div_u64(u64 a, u64 mul, u64 div);
|
||||
|
||||
#define DIV64_U64_ROUND_UP(ll, d) \
|
||||
({ u64 _tmp = (d); div64_u64((ll) + _tmp - 1, _tmp); })
|
||||
|
||||
|
||||
@ -153,9 +153,10 @@ struct psi_group {
|
||||
unsigned long avg[NR_PSI_STATES - 1][3];
|
||||
|
||||
/* Monitor work control */
|
||||
atomic_t poll_scheduled;
|
||||
struct kthread_worker __rcu *poll_kworker;
|
||||
struct kthread_delayed_work poll_work;
|
||||
struct task_struct __rcu *poll_task;
|
||||
struct timer_list poll_timer;
|
||||
wait_queue_head_t poll_wait;
|
||||
atomic_t poll_wakeup;
|
||||
|
||||
/* Protects data used by the monitor */
|
||||
struct mutex trigger_lock;
|
||||
|
||||
@ -155,24 +155,24 @@ struct task_group;
|
||||
*
|
||||
* for (;;) {
|
||||
* set_current_state(TASK_UNINTERRUPTIBLE);
|
||||
* if (!need_sleep)
|
||||
* break;
|
||||
* if (CONDITION)
|
||||
* break;
|
||||
*
|
||||
* schedule();
|
||||
* }
|
||||
* __set_current_state(TASK_RUNNING);
|
||||
*
|
||||
* If the caller does not need such serialisation (because, for instance, the
|
||||
* condition test and condition change and wakeup are under the same lock) then
|
||||
* CONDITION test and condition change and wakeup are under the same lock) then
|
||||
* use __set_current_state().
|
||||
*
|
||||
* The above is typically ordered against the wakeup, which does:
|
||||
*
|
||||
* need_sleep = false;
|
||||
* CONDITION = 1;
|
||||
* wake_up_state(p, TASK_UNINTERRUPTIBLE);
|
||||
*
|
||||
* where wake_up_state() executes a full memory barrier before accessing the
|
||||
* task state.
|
||||
* where wake_up_state()/try_to_wake_up() executes a full memory barrier before
|
||||
* accessing p->state.
|
||||
*
|
||||
* Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
|
||||
* once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
|
||||
@ -375,7 +375,7 @@ struct util_est {
|
||||
* For cfs_rq, they are the aggregated values of all runnable and blocked
|
||||
* sched_entities.
|
||||
*
|
||||
* The load/runnable/util_avg doesn't direcly factor frequency scaling and CPU
|
||||
* The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
|
||||
* capacity scaling. The scaling is done through the rq_clock_pelt that is used
|
||||
* for computing those signals (see update_rq_clock_pelt())
|
||||
*
|
||||
@ -687,9 +687,15 @@ struct task_struct {
|
||||
struct sched_dl_entity dl;
|
||||
|
||||
#ifdef CONFIG_UCLAMP_TASK
|
||||
/* Clamp values requested for a scheduling entity */
|
||||
/*
|
||||
* Clamp values requested for a scheduling entity.
|
||||
* Must be updated with task_rq_lock() held.
|
||||
*/
|
||||
struct uclamp_se uclamp_req[UCLAMP_CNT];
|
||||
/* Effective clamp values used for a scheduling entity */
|
||||
/*
|
||||
* Effective clamp values used for a scheduling entity.
|
||||
* Must be updated with task_rq_lock() held.
|
||||
*/
|
||||
struct uclamp_se uclamp[UCLAMP_CNT];
|
||||
#endif
|
||||
|
||||
@ -2039,6 +2045,7 @@ const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
|
||||
const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
|
||||
|
||||
int sched_trace_rq_cpu(struct rq *rq);
|
||||
int sched_trace_rq_nr_running(struct rq *rq);
|
||||
|
||||
const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
|
||||
|
||||
|
||||
@ -14,6 +14,7 @@ enum hk_flags {
|
||||
HK_FLAG_DOMAIN = (1 << 5),
|
||||
HK_FLAG_WQ = (1 << 6),
|
||||
HK_FLAG_MANAGED_IRQ = (1 << 7),
|
||||
HK_FLAG_KTHREAD = (1 << 8),
|
||||
};
|
||||
|
||||
#ifdef CONFIG_CPU_ISOLATION
|
||||
|
||||
@ -43,6 +43,6 @@ extern unsigned long calc_load_n(unsigned long load, unsigned long exp,
|
||||
#define LOAD_INT(x) ((x) >> FSHIFT)
|
||||
#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
|
||||
|
||||
extern void calc_global_load(unsigned long ticks);
|
||||
extern void calc_global_load(void);
|
||||
|
||||
#endif /* _LINUX_SCHED_LOADAVG_H */
|
||||
|
||||
@ -23,7 +23,7 @@ extern struct mm_struct *mm_alloc(void);
|
||||
* will still exist later on and mmget_not_zero() has to be used before
|
||||
* accessing it.
|
||||
*
|
||||
* This is a preferred way to to pin @mm for a longer/unbounded amount
|
||||
* This is a preferred way to pin @mm for a longer/unbounded amount
|
||||
* of time.
|
||||
*
|
||||
* Use mmdrop() to release the reference acquired by mmgrab().
|
||||
@ -49,8 +49,6 @@ static inline void mmdrop(struct mm_struct *mm)
|
||||
__mmdrop(mm);
|
||||
}
|
||||
|
||||
void mmdrop(struct mm_struct *mm);
|
||||
|
||||
/*
|
||||
* This has to be called after a get_task_mm()/mmget_not_zero()
|
||||
* followed by taking the mmap_lock for writing before modifying the
|
||||
@ -234,7 +232,7 @@ static inline unsigned int memalloc_noio_save(void)
|
||||
* @flags: Flags to restore.
|
||||
*
|
||||
* Ends the implicit GFP_NOIO scope started by memalloc_noio_save function.
|
||||
* Always make sure that that the given flags is the return value from the
|
||||
* Always make sure that the given flags is the return value from the
|
||||
* pairing memalloc_noio_save call.
|
||||
*/
|
||||
static inline void memalloc_noio_restore(unsigned int flags)
|
||||
@ -265,7 +263,7 @@ static inline unsigned int memalloc_nofs_save(void)
|
||||
* @flags: Flags to restore.
|
||||
*
|
||||
* Ends the implicit GFP_NOFS scope started by memalloc_nofs_save function.
|
||||
* Always make sure that that the given flags is the return value from the
|
||||
* Always make sure that the given flags is the return value from the
|
||||
* pairing memalloc_nofs_save call.
|
||||
*/
|
||||
static inline void memalloc_nofs_restore(unsigned int flags)
|
||||
|
||||
@ -61,9 +61,13 @@ int sched_proc_update_handler(struct ctl_table *table, int write,
|
||||
extern unsigned int sysctl_sched_rt_period;
|
||||
extern int sysctl_sched_rt_runtime;
|
||||
|
||||
extern unsigned int sysctl_sched_dl_period_max;
|
||||
extern unsigned int sysctl_sched_dl_period_min;
|
||||
|
||||
#ifdef CONFIG_UCLAMP_TASK
|
||||
extern unsigned int sysctl_sched_uclamp_util_min;
|
||||
extern unsigned int sysctl_sched_uclamp_util_max;
|
||||
extern unsigned int sysctl_sched_uclamp_util_min_rt_default;
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_CFS_BANDWIDTH
|
||||
|
||||
@ -55,6 +55,7 @@ extern asmlinkage void schedule_tail(struct task_struct *prev);
|
||||
extern void init_idle(struct task_struct *idle, int cpu);
|
||||
|
||||
extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
|
||||
extern void sched_post_fork(struct task_struct *p);
|
||||
extern void sched_dead(struct task_struct *p);
|
||||
|
||||
void __noreturn do_task_dead(void);
|
||||
|
||||
@ -217,6 +217,16 @@ static inline bool cpus_share_cache(int this_cpu, int that_cpu)
|
||||
#endif /* !CONFIG_SMP */
|
||||
|
||||
#ifndef arch_scale_cpu_capacity
|
||||
/**
|
||||
* arch_scale_cpu_capacity - get the capacity scale factor of a given CPU.
|
||||
* @cpu: the CPU in question.
|
||||
*
|
||||
* Return: the CPU scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
|
||||
*
|
||||
* max_perf(cpu)
|
||||
* ----------------------------- * SCHED_CAPACITY_SCALE
|
||||
* max(max_perf(c) : c \in CPUs)
|
||||
*/
|
||||
static __always_inline
|
||||
unsigned long arch_scale_cpu_capacity(int cpu)
|
||||
{
|
||||
@ -232,6 +242,13 @@ unsigned long arch_scale_thermal_pressure(int cpu)
|
||||
}
|
||||
#endif
|
||||
|
||||
#ifndef arch_set_thermal_pressure
|
||||
static __always_inline
|
||||
void arch_set_thermal_pressure(const struct cpumask *cpus,
|
||||
unsigned long th_pressure)
|
||||
{ }
|
||||
#endif
|
||||
|
||||
static inline int task_node(const struct task_struct *p)
|
||||
{
|
||||
return cpu_to_node(task_cpu(p));
|
||||
|
||||
@ -91,7 +91,7 @@ DEFINE_EVENT(sched_wakeup_template, sched_waking,
|
||||
|
||||
/*
|
||||
* Tracepoint called when the task is actually woken; p->state == TASK_RUNNNG.
|
||||
* It it not always called from the waking context.
|
||||
* It is not always called from the waking context.
|
||||
*/
|
||||
DEFINE_EVENT(sched_wakeup_template, sched_wakeup,
|
||||
TP_PROTO(struct task_struct *p),
|
||||
@ -634,6 +634,18 @@ DECLARE_TRACE(sched_overutilized_tp,
|
||||
TP_PROTO(struct root_domain *rd, bool overutilized),
|
||||
TP_ARGS(rd, overutilized));
|
||||
|
||||
DECLARE_TRACE(sched_util_est_cfs_tp,
|
||||
TP_PROTO(struct cfs_rq *cfs_rq),
|
||||
TP_ARGS(cfs_rq));
|
||||
|
||||
DECLARE_TRACE(sched_util_est_se_tp,
|
||||
TP_PROTO(struct sched_entity *se),
|
||||
TP_ARGS(se));
|
||||
|
||||
DECLARE_TRACE(sched_update_nr_running_tp,
|
||||
TP_PROTO(struct rq *rq, int change),
|
||||
TP_ARGS(rq, change));
|
||||
|
||||
#endif /* _TRACE_SCHED_H */
|
||||
|
||||
/* This part must be outside protection */
|
||||
|
||||
17
init/Kconfig
17
init/Kconfig
@ -492,8 +492,23 @@ config HAVE_SCHED_AVG_IRQ
|
||||
depends on SMP
|
||||
|
||||
config SCHED_THERMAL_PRESSURE
|
||||
bool "Enable periodic averaging of thermal pressure"
|
||||
bool
|
||||
default y if ARM && ARM_CPU_TOPOLOGY
|
||||
default y if ARM64
|
||||
depends on SMP
|
||||
depends on CPU_FREQ_THERMAL
|
||||
help
|
||||
Select this option to enable thermal pressure accounting in the
|
||||
scheduler. Thermal pressure is the value conveyed to the scheduler
|
||||
that reflects the reduction in CPU compute capacity resulted from
|
||||
thermal throttling. Thermal throttling occurs when the performance of
|
||||
a CPU is capped due to high operating temperatures.
|
||||
|
||||
If selected, the scheduler will be able to balance tasks accordingly,
|
||||
i.e. put less load on throttled CPUs than on non/less throttled ones.
|
||||
|
||||
This requires the architecture to implement
|
||||
arch_set_thermal_pressure() and arch_get_thermal_pressure().
|
||||
|
||||
config BSD_PROCESS_ACCT
|
||||
bool "BSD Process Accounting"
|
||||
|
||||
@ -2302,6 +2302,7 @@ static __latent_entropy struct task_struct *copy_process(
|
||||
write_unlock_irq(&tasklist_lock);
|
||||
|
||||
proc_fork_connector(p);
|
||||
sched_post_fork(p);
|
||||
cgroup_post_fork(p, args);
|
||||
perf_event_fork(p);
|
||||
|
||||
|
||||
@ -27,6 +27,7 @@
|
||||
#include <linux/ptrace.h>
|
||||
#include <linux/uaccess.h>
|
||||
#include <linux/numa.h>
|
||||
#include <linux/sched/isolation.h>
|
||||
#include <trace/events/sched.h>
|
||||
|
||||
|
||||
@ -383,7 +384,8 @@ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
|
||||
* The kernel thread should not inherit these properties.
|
||||
*/
|
||||
sched_setscheduler_nocheck(task, SCHED_NORMAL, ¶m);
|
||||
set_cpus_allowed_ptr(task, cpu_all_mask);
|
||||
set_cpus_allowed_ptr(task,
|
||||
housekeeping_cpumask(HK_FLAG_KTHREAD));
|
||||
}
|
||||
kfree(create);
|
||||
return task;
|
||||
@ -608,7 +610,7 @@ int kthreadd(void *unused)
|
||||
/* Setup a clean context for our children to inherit. */
|
||||
set_task_comm(tsk, "kthreadd");
|
||||
ignore_signals(tsk);
|
||||
set_cpus_allowed_ptr(tsk, cpu_all_mask);
|
||||
set_cpus_allowed_ptr(tsk, housekeeping_cpumask(HK_FLAG_KTHREAD));
|
||||
set_mems_allowed(node_states[N_MEMORY]);
|
||||
|
||||
current->flags |= PF_NOFREEZE;
|
||||
|
||||
@ -6,6 +6,10 @@
|
||||
*
|
||||
* Copyright (C) 1991-2002 Linus Torvalds
|
||||
*/
|
||||
#define CREATE_TRACE_POINTS
|
||||
#include <trace/events/sched.h>
|
||||
#undef CREATE_TRACE_POINTS
|
||||
|
||||
#include "sched.h"
|
||||
|
||||
#include <linux/nospec.h>
|
||||
@ -23,9 +27,6 @@
|
||||
#include "pelt.h"
|
||||
#include "smp.h"
|
||||
|
||||
#define CREATE_TRACE_POINTS
|
||||
#include <trace/events/sched.h>
|
||||
|
||||
/*
|
||||
* Export tracepoints that act as a bare tracehook (ie: have no trace event
|
||||
* associated with them) to allow external modules to probe them.
|
||||
@ -36,6 +37,9 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(pelt_dl_tp);
|
||||
EXPORT_TRACEPOINT_SYMBOL_GPL(pelt_irq_tp);
|
||||
EXPORT_TRACEPOINT_SYMBOL_GPL(pelt_se_tp);
|
||||
EXPORT_TRACEPOINT_SYMBOL_GPL(sched_overutilized_tp);
|
||||
EXPORT_TRACEPOINT_SYMBOL_GPL(sched_util_est_cfs_tp);
|
||||
EXPORT_TRACEPOINT_SYMBOL_GPL(sched_util_est_se_tp);
|
||||
EXPORT_TRACEPOINT_SYMBOL_GPL(sched_update_nr_running_tp);
|
||||
|
||||
DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
|
||||
|
||||
@ -75,6 +79,100 @@ __read_mostly int scheduler_running;
|
||||
*/
|
||||
int sysctl_sched_rt_runtime = 950000;
|
||||
|
||||
|
||||
/*
|
||||
* Serialization rules:
|
||||
*
|
||||
* Lock order:
|
||||
*
|
||||
* p->pi_lock
|
||||
* rq->lock
|
||||
* hrtimer_cpu_base->lock (hrtimer_start() for bandwidth controls)
|
||||
*
|
||||
* rq1->lock
|
||||
* rq2->lock where: rq1 < rq2
|
||||
*
|
||||
* Regular state:
|
||||
*
|
||||
* Normal scheduling state is serialized by rq->lock. __schedule() takes the
|
||||
* local CPU's rq->lock, it optionally removes the task from the runqueue and
|
||||
* always looks at the local rq data structures to find the most elegible task
|
||||
* to run next.
|
||||
*
|
||||
* Task enqueue is also under rq->lock, possibly taken from another CPU.
|
||||
* Wakeups from another LLC domain might use an IPI to transfer the enqueue to
|
||||
* the local CPU to avoid bouncing the runqueue state around [ see
|
||||
* ttwu_queue_wakelist() ]
|
||||
*
|
||||
* Task wakeup, specifically wakeups that involve migration, are horribly
|
||||
* complicated to avoid having to take two rq->locks.
|
||||
*
|
||||
* Special state:
|
||||
*
|
||||
* System-calls and anything external will use task_rq_lock() which acquires
|
||||
* both p->pi_lock and rq->lock. As a consequence the state they change is
|
||||
* stable while holding either lock:
|
||||
*
|
||||
* - sched_setaffinity()/
|
||||
* set_cpus_allowed_ptr(): p->cpus_ptr, p->nr_cpus_allowed
|
||||
* - set_user_nice(): p->se.load, p->*prio
|
||||
* - __sched_setscheduler(): p->sched_class, p->policy, p->*prio,
|
||||
* p->se.load, p->rt_priority,
|
||||
* p->dl.dl_{runtime, deadline, period, flags, bw, density}
|
||||
* - sched_setnuma(): p->numa_preferred_nid
|
||||
* - sched_move_task()/
|
||||
* cpu_cgroup_fork(): p->sched_task_group
|
||||
* - uclamp_update_active() p->uclamp*
|
||||
*
|
||||
* p->state <- TASK_*:
|
||||
*
|
||||
* is changed locklessly using set_current_state(), __set_current_state() or
|
||||
* set_special_state(), see their respective comments, or by
|
||||
* try_to_wake_up(). This latter uses p->pi_lock to serialize against
|
||||
* concurrent self.
|
||||
*
|
||||
* p->on_rq <- { 0, 1 = TASK_ON_RQ_QUEUED, 2 = TASK_ON_RQ_MIGRATING }:
|
||||
*
|
||||
* is set by activate_task() and cleared by deactivate_task(), under
|
||||
* rq->lock. Non-zero indicates the task is runnable, the special
|
||||
* ON_RQ_MIGRATING state is used for migration without holding both
|
||||
* rq->locks. It indicates task_cpu() is not stable, see task_rq_lock().
|
||||
*
|
||||
* p->on_cpu <- { 0, 1 }:
|
||||
*
|
||||
* is set by prepare_task() and cleared by finish_task() such that it will be
|
||||
* set before p is scheduled-in and cleared after p is scheduled-out, both
|
||||
* under rq->lock. Non-zero indicates the task is running on its CPU.
|
||||
*
|
||||
* [ The astute reader will observe that it is possible for two tasks on one
|
||||
* CPU to have ->on_cpu = 1 at the same time. ]
|
||||
*
|
||||
* task_cpu(p): is changed by set_task_cpu(), the rules are:
|
||||
*
|
||||
* - Don't call set_task_cpu() on a blocked task:
|
||||
*
|
||||
* We don't care what CPU we're not running on, this simplifies hotplug,
|
||||
* the CPU assignment of blocked tasks isn't required to be valid.
|
||||
*
|
||||
* - for try_to_wake_up(), called under p->pi_lock:
|
||||
*
|
||||
* This allows try_to_wake_up() to only take one rq->lock, see its comment.
|
||||
*
|
||||
* - for migration called under rq->lock:
|
||||
* [ see task_on_rq_migrating() in task_rq_lock() ]
|
||||
*
|
||||
* o move_queued_task()
|
||||
* o detach_task()
|
||||
*
|
||||
* - for migration called under double_rq_lock():
|
||||
*
|
||||
* o __migrate_swap_task()
|
||||
* o push_rt_task() / pull_rt_task()
|
||||
* o push_dl_task() / pull_dl_task()
|
||||
* o dl_task_offline_migration()
|
||||
*
|
||||
*/
|
||||
|
||||
/*
|
||||
* __task_rq_lock - lock the rq @p resides on.
|
||||
*/
|
||||
@ -791,9 +889,46 @@ unsigned int sysctl_sched_uclamp_util_min = SCHED_CAPACITY_SCALE;
|
||||
/* Max allowed maximum utilization */
|
||||
unsigned int sysctl_sched_uclamp_util_max = SCHED_CAPACITY_SCALE;
|
||||
|
||||
/*
|
||||
* By default RT tasks run at the maximum performance point/capacity of the
|
||||
* system. Uclamp enforces this by always setting UCLAMP_MIN of RT tasks to
|
||||
* SCHED_CAPACITY_SCALE.
|
||||
*
|
||||
* This knob allows admins to change the default behavior when uclamp is being
|
||||
* used. In battery powered devices, particularly, running at the maximum
|
||||
* capacity and frequency will increase energy consumption and shorten the
|
||||
* battery life.
|
||||
*
|
||||
* This knob only affects RT tasks that their uclamp_se->user_defined == false.
|
||||
*
|
||||
* This knob will not override the system default sched_util_clamp_min defined
|
||||
* above.
|
||||
*/
|
||||
unsigned int sysctl_sched_uclamp_util_min_rt_default = SCHED_CAPACITY_SCALE;
|
||||
|
||||
/* All clamps are required to be less or equal than these values */
|
||||
static struct uclamp_se uclamp_default[UCLAMP_CNT];
|
||||
|
||||
/*
|
||||
* This static key is used to reduce the uclamp overhead in the fast path. It
|
||||
* primarily disables the call to uclamp_rq_{inc, dec}() in
|
||||
* enqueue/dequeue_task().
|
||||
*
|
||||
* This allows users to continue to enable uclamp in their kernel config with
|
||||
* minimum uclamp overhead in the fast path.
|
||||
*
|
||||
* As soon as userspace modifies any of the uclamp knobs, the static key is
|
||||
* enabled, since we have an actual users that make use of uclamp
|
||||
* functionality.
|
||||
*
|
||||
* The knobs that would enable this static key are:
|
||||
*
|
||||
* * A task modifying its uclamp value with sched_setattr().
|
||||
* * An admin modifying the sysctl_sched_uclamp_{min, max} via procfs.
|
||||
* * An admin modifying the cgroup cpu.uclamp.{min, max}
|
||||
*/
|
||||
DEFINE_STATIC_KEY_FALSE(sched_uclamp_used);
|
||||
|
||||
/* Integer rounded range for each bucket */
|
||||
#define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS)
|
||||
|
||||
@ -873,6 +1008,64 @@ unsigned int uclamp_rq_max_value(struct rq *rq, enum uclamp_id clamp_id,
|
||||
return uclamp_idle_value(rq, clamp_id, clamp_value);
|
||||
}
|
||||
|
||||
static void __uclamp_update_util_min_rt_default(struct task_struct *p)
|
||||
{
|
||||
unsigned int default_util_min;
|
||||
struct uclamp_se *uc_se;
|
||||
|
||||
lockdep_assert_held(&p->pi_lock);
|
||||
|
||||
uc_se = &p->uclamp_req[UCLAMP_MIN];
|
||||
|
||||
/* Only sync if user didn't override the default */
|
||||
if (uc_se->user_defined)
|
||||
return;
|
||||
|
||||
default_util_min = sysctl_sched_uclamp_util_min_rt_default;
|
||||
uclamp_se_set(uc_se, default_util_min, false);
|
||||
}
|
||||
|
||||
static void uclamp_update_util_min_rt_default(struct task_struct *p)
|
||||
{
|
||||
struct rq_flags rf;
|
||||
struct rq *rq;
|
||||
|
||||
if (!rt_task(p))
|
||||
return;
|
||||
|
||||
/* Protect updates to p->uclamp_* */
|
||||
rq = task_rq_lock(p, &rf);
|
||||
__uclamp_update_util_min_rt_default(p);
|
||||
task_rq_unlock(rq, p, &rf);
|
||||
}
|
||||
|
||||
static void uclamp_sync_util_min_rt_default(void)
|
||||
{
|
||||
struct task_struct *g, *p;
|
||||
|
||||
/*
|
||||
* copy_process() sysctl_uclamp
|
||||
* uclamp_min_rt = X;
|
||||
* write_lock(&tasklist_lock) read_lock(&tasklist_lock)
|
||||
* // link thread smp_mb__after_spinlock()
|
||||
* write_unlock(&tasklist_lock) read_unlock(&tasklist_lock);
|
||||
* sched_post_fork() for_each_process_thread()
|
||||
* __uclamp_sync_rt() __uclamp_sync_rt()
|
||||
*
|
||||
* Ensures that either sched_post_fork() will observe the new
|
||||
* uclamp_min_rt or for_each_process_thread() will observe the new
|
||||
* task.
|
||||
*/
|
||||
read_lock(&tasklist_lock);
|
||||
smp_mb__after_spinlock();
|
||||
read_unlock(&tasklist_lock);
|
||||
|
||||
rcu_read_lock();
|
||||
for_each_process_thread(g, p)
|
||||
uclamp_update_util_min_rt_default(p);
|
||||
rcu_read_unlock();
|
||||
}
|
||||
|
||||
static inline struct uclamp_se
|
||||
uclamp_tg_restrict(struct task_struct *p, enum uclamp_id clamp_id)
|
||||
{
|
||||
@ -990,10 +1183,38 @@ static inline void uclamp_rq_dec_id(struct rq *rq, struct task_struct *p,
|
||||
|
||||
lockdep_assert_held(&rq->lock);
|
||||
|
||||
/*
|
||||
* If sched_uclamp_used was enabled after task @p was enqueued,
|
||||
* we could end up with unbalanced call to uclamp_rq_dec_id().
|
||||
*
|
||||
* In this case the uc_se->active flag should be false since no uclamp
|
||||
* accounting was performed at enqueue time and we can just return
|
||||
* here.
|
||||
*
|
||||
* Need to be careful of the following enqeueue/dequeue ordering
|
||||
* problem too
|
||||
*
|
||||
* enqueue(taskA)
|
||||
* // sched_uclamp_used gets enabled
|
||||
* enqueue(taskB)
|
||||
* dequeue(taskA)
|
||||
* // Must not decrement bukcet->tasks here
|
||||
* dequeue(taskB)
|
||||
*
|
||||
* where we could end up with stale data in uc_se and
|
||||
* bucket[uc_se->bucket_id].
|
||||
*
|
||||
* The following check here eliminates the possibility of such race.
|
||||
*/
|
||||
if (unlikely(!uc_se->active))
|
||||
return;
|
||||
|
||||
bucket = &uc_rq->bucket[uc_se->bucket_id];
|
||||
|
||||
SCHED_WARN_ON(!bucket->tasks);
|
||||
if (likely(bucket->tasks))
|
||||
bucket->tasks--;
|
||||
|
||||
uc_se->active = false;
|
||||
|
||||
/*
|
||||
@ -1021,6 +1242,15 @@ static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p)
|
||||
{
|
||||
enum uclamp_id clamp_id;
|
||||
|
||||
/*
|
||||
* Avoid any overhead until uclamp is actually used by the userspace.
|
||||
*
|
||||
* The condition is constructed such that a NOP is generated when
|
||||
* sched_uclamp_used is disabled.
|
||||
*/
|
||||
if (!static_branch_unlikely(&sched_uclamp_used))
|
||||
return;
|
||||
|
||||
if (unlikely(!p->sched_class->uclamp_enabled))
|
||||
return;
|
||||
|
||||
@ -1036,6 +1266,15 @@ static inline void uclamp_rq_dec(struct rq *rq, struct task_struct *p)
|
||||
{
|
||||
enum uclamp_id clamp_id;
|
||||
|
||||
/*
|
||||
* Avoid any overhead until uclamp is actually used by the userspace.
|
||||
*
|
||||
* The condition is constructed such that a NOP is generated when
|
||||
* sched_uclamp_used is disabled.
|
||||
*/
|
||||
if (!static_branch_unlikely(&sched_uclamp_used))
|
||||
return;
|
||||
|
||||
if (unlikely(!p->sched_class->uclamp_enabled))
|
||||
return;
|
||||
|
||||
@ -1114,12 +1353,13 @@ int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
|
||||
void *buffer, size_t *lenp, loff_t *ppos)
|
||||
{
|
||||
bool update_root_tg = false;
|
||||
int old_min, old_max;
|
||||
int old_min, old_max, old_min_rt;
|
||||
int result;
|
||||
|
||||
mutex_lock(&uclamp_mutex);
|
||||
old_min = sysctl_sched_uclamp_util_min;
|
||||
old_max = sysctl_sched_uclamp_util_max;
|
||||
old_min_rt = sysctl_sched_uclamp_util_min_rt_default;
|
||||
|
||||
result = proc_dointvec(table, write, buffer, lenp, ppos);
|
||||
if (result)
|
||||
@ -1128,7 +1368,9 @@ int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
|
||||
goto done;
|
||||
|
||||
if (sysctl_sched_uclamp_util_min > sysctl_sched_uclamp_util_max ||
|
||||
sysctl_sched_uclamp_util_max > SCHED_CAPACITY_SCALE) {
|
||||
sysctl_sched_uclamp_util_max > SCHED_CAPACITY_SCALE ||
|
||||
sysctl_sched_uclamp_util_min_rt_default > SCHED_CAPACITY_SCALE) {
|
||||
|
||||
result = -EINVAL;
|
||||
goto undo;
|
||||
}
|
||||
@ -1144,8 +1386,15 @@ int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
|
||||
update_root_tg = true;
|
||||
}
|
||||
|
||||
if (update_root_tg)
|
||||
if (update_root_tg) {
|
||||
static_branch_enable(&sched_uclamp_used);
|
||||
uclamp_update_root_tg();
|
||||
}
|
||||
|
||||
if (old_min_rt != sysctl_sched_uclamp_util_min_rt_default) {
|
||||
static_branch_enable(&sched_uclamp_used);
|
||||
uclamp_sync_util_min_rt_default();
|
||||
}
|
||||
|
||||
/*
|
||||
* We update all RUNNABLE tasks only when task groups are in use.
|
||||
@ -1158,6 +1407,7 @@ int sysctl_sched_uclamp_handler(struct ctl_table *table, int write,
|
||||
undo:
|
||||
sysctl_sched_uclamp_util_min = old_min;
|
||||
sysctl_sched_uclamp_util_max = old_max;
|
||||
sysctl_sched_uclamp_util_min_rt_default = old_min_rt;
|
||||
done:
|
||||
mutex_unlock(&uclamp_mutex);
|
||||
|
||||
@ -1180,6 +1430,15 @@ static int uclamp_validate(struct task_struct *p,
|
||||
if (upper_bound > SCHED_CAPACITY_SCALE)
|
||||
return -EINVAL;
|
||||
|
||||
/*
|
||||
* We have valid uclamp attributes; make sure uclamp is enabled.
|
||||
*
|
||||
* We need to do that here, because enabling static branches is a
|
||||
* blocking operation which obviously cannot be done while holding
|
||||
* scheduler locks.
|
||||
*/
|
||||
static_branch_enable(&sched_uclamp_used);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -1194,17 +1453,20 @@ static void __setscheduler_uclamp(struct task_struct *p,
|
||||
*/
|
||||
for_each_clamp_id(clamp_id) {
|
||||
struct uclamp_se *uc_se = &p->uclamp_req[clamp_id];
|
||||
unsigned int clamp_value = uclamp_none(clamp_id);
|
||||
|
||||
/* Keep using defined clamps across class changes */
|
||||
if (uc_se->user_defined)
|
||||
continue;
|
||||
|
||||
/* By default, RT tasks always get 100% boost */
|
||||
/*
|
||||
* RT by default have a 100% boost value that could be modified
|
||||
* at runtime.
|
||||
*/
|
||||
if (unlikely(rt_task(p) && clamp_id == UCLAMP_MIN))
|
||||
clamp_value = uclamp_none(UCLAMP_MAX);
|
||||
__uclamp_update_util_min_rt_default(p);
|
||||
else
|
||||
uclamp_se_set(uc_se, uclamp_none(clamp_id), false);
|
||||
|
||||
uclamp_se_set(uc_se, clamp_value, false);
|
||||
}
|
||||
|
||||
if (likely(!(attr->sched_flags & SCHED_FLAG_UTIL_CLAMP)))
|
||||
@ -1225,6 +1487,10 @@ static void uclamp_fork(struct task_struct *p)
|
||||
{
|
||||
enum uclamp_id clamp_id;
|
||||
|
||||
/*
|
||||
* We don't need to hold task_rq_lock() when updating p->uclamp_* here
|
||||
* as the task is still at its early fork stages.
|
||||
*/
|
||||
for_each_clamp_id(clamp_id)
|
||||
p->uclamp[clamp_id].active = false;
|
||||
|
||||
@ -1237,19 +1503,33 @@ static void uclamp_fork(struct task_struct *p)
|
||||
}
|
||||
}
|
||||
|
||||
static void uclamp_post_fork(struct task_struct *p)
|
||||
{
|
||||
uclamp_update_util_min_rt_default(p);
|
||||
}
|
||||
|
||||
static void __init init_uclamp_rq(struct rq *rq)
|
||||
{
|
||||
enum uclamp_id clamp_id;
|
||||
struct uclamp_rq *uc_rq = rq->uclamp;
|
||||
|
||||
for_each_clamp_id(clamp_id) {
|
||||
uc_rq[clamp_id] = (struct uclamp_rq) {
|
||||
.value = uclamp_none(clamp_id)
|
||||
};
|
||||
}
|
||||
|
||||
rq->uclamp_flags = 0;
|
||||
}
|
||||
|
||||
static void __init init_uclamp(void)
|
||||
{
|
||||
struct uclamp_se uc_max = {};
|
||||
enum uclamp_id clamp_id;
|
||||
int cpu;
|
||||
|
||||
mutex_init(&uclamp_mutex);
|
||||
|
||||
for_each_possible_cpu(cpu) {
|
||||
memset(&cpu_rq(cpu)->uclamp, 0,
|
||||
sizeof(struct uclamp_rq)*UCLAMP_CNT);
|
||||
cpu_rq(cpu)->uclamp_flags = 0;
|
||||
}
|
||||
for_each_possible_cpu(cpu)
|
||||
init_uclamp_rq(cpu_rq(cpu));
|
||||
|
||||
for_each_clamp_id(clamp_id) {
|
||||
uclamp_se_set(&init_task.uclamp_req[clamp_id],
|
||||
@ -1278,6 +1558,7 @@ static inline int uclamp_validate(struct task_struct *p,
|
||||
static void __setscheduler_uclamp(struct task_struct *p,
|
||||
const struct sched_attr *attr) { }
|
||||
static inline void uclamp_fork(struct task_struct *p) { }
|
||||
static inline void uclamp_post_fork(struct task_struct *p) { }
|
||||
static inline void init_uclamp(void) { }
|
||||
#endif /* CONFIG_UCLAMP_TASK */
|
||||
|
||||
@ -1404,20 +1685,10 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
|
||||
|
||||
void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
|
||||
{
|
||||
const struct sched_class *class;
|
||||
|
||||
if (p->sched_class == rq->curr->sched_class) {
|
||||
if (p->sched_class == rq->curr->sched_class)
|
||||
rq->curr->sched_class->check_preempt_curr(rq, p, flags);
|
||||
} else {
|
||||
for_each_class(class) {
|
||||
if (class == rq->curr->sched_class)
|
||||
break;
|
||||
if (class == p->sched_class) {
|
||||
resched_curr(rq);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
else if (p->sched_class > rq->curr->sched_class)
|
||||
resched_curr(rq);
|
||||
|
||||
/*
|
||||
* A queue event has occurred, and we're going to schedule. In
|
||||
@ -1468,8 +1739,7 @@ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf,
|
||||
{
|
||||
lockdep_assert_held(&rq->lock);
|
||||
|
||||
WRITE_ONCE(p->on_rq, TASK_ON_RQ_MIGRATING);
|
||||
dequeue_task(rq, p, DEQUEUE_NOCLOCK);
|
||||
deactivate_task(rq, p, DEQUEUE_NOCLOCK);
|
||||
set_task_cpu(p, new_cpu);
|
||||
rq_unlock(rq, rf);
|
||||
|
||||
@ -1477,8 +1747,7 @@ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf,
|
||||
|
||||
rq_lock(rq, rf);
|
||||
BUG_ON(task_cpu(p) != new_cpu);
|
||||
enqueue_task(rq, p, 0);
|
||||
p->on_rq = TASK_ON_RQ_QUEUED;
|
||||
activate_task(rq, p, 0);
|
||||
check_preempt_curr(rq, p, 0);
|
||||
|
||||
return rq;
|
||||
@ -2243,12 +2512,31 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags,
|
||||
}
|
||||
|
||||
/*
|
||||
* Called in case the task @p isn't fully descheduled from its runqueue,
|
||||
* in this case we must do a remote wakeup. Its a 'light' wakeup though,
|
||||
* since all we need to do is flip p->state to TASK_RUNNING, since
|
||||
* the task is still ->on_rq.
|
||||
* Consider @p being inside a wait loop:
|
||||
*
|
||||
* for (;;) {
|
||||
* set_current_state(TASK_UNINTERRUPTIBLE);
|
||||
*
|
||||
* if (CONDITION)
|
||||
* break;
|
||||
*
|
||||
* schedule();
|
||||
* }
|
||||
* __set_current_state(TASK_RUNNING);
|
||||
*
|
||||
* between set_current_state() and schedule(). In this case @p is still
|
||||
* runnable, so all that needs doing is change p->state back to TASK_RUNNING in
|
||||
* an atomic manner.
|
||||
*
|
||||
* By taking task_rq(p)->lock we serialize against schedule(), if @p->on_rq
|
||||
* then schedule() must still happen and p->state can be changed to
|
||||
* TASK_RUNNING. Otherwise we lost the race, schedule() has happened, and we
|
||||
* need to do a full wakeup with enqueue.
|
||||
*
|
||||
* Returns: %true when the wakeup is done,
|
||||
* %false otherwise.
|
||||
*/
|
||||
static int ttwu_remote(struct task_struct *p, int wake_flags)
|
||||
static int ttwu_runnable(struct task_struct *p, int wake_flags)
|
||||
{
|
||||
struct rq_flags rf;
|
||||
struct rq *rq;
|
||||
@ -2389,6 +2677,14 @@ static bool ttwu_queue_wakelist(struct task_struct *p, int cpu, int wake_flags)
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
#else /* !CONFIG_SMP */
|
||||
|
||||
static inline bool ttwu_queue_wakelist(struct task_struct *p, int cpu, int wake_flags)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
#endif /* CONFIG_SMP */
|
||||
|
||||
static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags)
|
||||
@ -2396,10 +2692,8 @@ static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags)
|
||||
struct rq *rq = cpu_rq(cpu);
|
||||
struct rq_flags rf;
|
||||
|
||||
#if defined(CONFIG_SMP)
|
||||
if (ttwu_queue_wakelist(p, cpu, wake_flags))
|
||||
return;
|
||||
#endif
|
||||
|
||||
rq_lock(rq, &rf);
|
||||
update_rq_clock(rq);
|
||||
@ -2455,8 +2749,8 @@ static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags)
|
||||
* migration. However the means are completely different as there is no lock
|
||||
* chain to provide order. Instead we do:
|
||||
*
|
||||
* 1) smp_store_release(X->on_cpu, 0)
|
||||
* 2) smp_cond_load_acquire(!X->on_cpu)
|
||||
* 1) smp_store_release(X->on_cpu, 0) -- finish_task()
|
||||
* 2) smp_cond_load_acquire(!X->on_cpu) -- try_to_wake_up()
|
||||
*
|
||||
* Example:
|
||||
*
|
||||
@ -2496,15 +2790,33 @@ static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags)
|
||||
* @state: the mask of task states that can be woken
|
||||
* @wake_flags: wake modifier flags (WF_*)
|
||||
*
|
||||
* If (@state & @p->state) @p->state = TASK_RUNNING.
|
||||
* Conceptually does:
|
||||
*
|
||||
* If (@state & @p->state) @p->state = TASK_RUNNING.
|
||||
*
|
||||
* If the task was not queued/runnable, also place it back on a runqueue.
|
||||
*
|
||||
* Atomic against schedule() which would dequeue a task, also see
|
||||
* set_current_state().
|
||||
* This function is atomic against schedule() which would dequeue the task.
|
||||
*
|
||||
* This function executes a full memory barrier before accessing the task
|
||||
* state; see set_current_state().
|
||||
* It issues a full memory barrier before accessing @p->state, see the comment
|
||||
* with set_current_state().
|
||||
*
|
||||
* Uses p->pi_lock to serialize against concurrent wake-ups.
|
||||
*
|
||||
* Relies on p->pi_lock stabilizing:
|
||||
* - p->sched_class
|
||||
* - p->cpus_ptr
|
||||
* - p->sched_task_group
|
||||
* in order to do migration, see its use of select_task_rq()/set_task_cpu().
|
||||
*
|
||||
* Tries really hard to only take one task_rq(p)->lock for performance.
|
||||
* Takes rq->lock in:
|
||||
* - ttwu_runnable() -- old rq, unavoidable, see comment there;
|
||||
* - ttwu_queue() -- new rq, for enqueue of the task;
|
||||
* - psi_ttwu_dequeue() -- much sadness :-( accounting will kill us.
|
||||
*
|
||||
* As a consequence we race really badly with just about everything. See the
|
||||
* many memory barriers and their comments for details.
|
||||
*
|
||||
* Return: %true if @p->state changes (an actual wakeup was done),
|
||||
* %false otherwise.
|
||||
@ -2520,7 +2832,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
|
||||
/*
|
||||
* We're waking current, this means 'p->on_rq' and 'task_cpu(p)
|
||||
* == smp_processor_id()'. Together this means we can special
|
||||
* case the whole 'p->on_rq && ttwu_remote()' case below
|
||||
* case the whole 'p->on_rq && ttwu_runnable()' case below
|
||||
* without taking any locks.
|
||||
*
|
||||
* In particular:
|
||||
@ -2541,8 +2853,8 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
|
||||
/*
|
||||
* If we are going to wake up a thread waiting for CONDITION we
|
||||
* need to ensure that CONDITION=1 done by the caller can not be
|
||||
* reordered with p->state check below. This pairs with mb() in
|
||||
* set_current_state() the waiting thread does.
|
||||
* reordered with p->state check below. This pairs with smp_store_mb()
|
||||
* in set_current_state() that the waiting thread does.
|
||||
*/
|
||||
raw_spin_lock_irqsave(&p->pi_lock, flags);
|
||||
smp_mb__after_spinlock();
|
||||
@ -2577,7 +2889,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
|
||||
* A similar smb_rmb() lives in try_invoke_on_locked_down_task().
|
||||
*/
|
||||
smp_rmb();
|
||||
if (READ_ONCE(p->on_rq) && ttwu_remote(p, wake_flags))
|
||||
if (READ_ONCE(p->on_rq) && ttwu_runnable(p, wake_flags))
|
||||
goto unlock;
|
||||
|
||||
if (p->in_iowait) {
|
||||
@ -2990,6 +3302,11 @@ int sched_fork(unsigned long clone_flags, struct task_struct *p)
|
||||
return 0;
|
||||
}
|
||||
|
||||
void sched_post_fork(struct task_struct *p)
|
||||
{
|
||||
uclamp_post_fork(p);
|
||||
}
|
||||
|
||||
unsigned long to_ratio(u64 period, u64 runtime)
|
||||
{
|
||||
if (runtime == RUNTIME_INF)
|
||||
@ -3147,8 +3464,10 @@ static inline void prepare_task(struct task_struct *next)
|
||||
/*
|
||||
* Claim the task as running, we do this before switching to it
|
||||
* such that any running task will have this set.
|
||||
*
|
||||
* See the ttwu() WF_ON_CPU case and its ordering comment.
|
||||
*/
|
||||
next->on_cpu = 1;
|
||||
WRITE_ONCE(next->on_cpu, 1);
|
||||
#endif
|
||||
}
|
||||
|
||||
@ -3156,8 +3475,9 @@ static inline void finish_task(struct task_struct *prev)
|
||||
{
|
||||
#ifdef CONFIG_SMP
|
||||
/*
|
||||
* After ->on_cpu is cleared, the task can be moved to a different CPU.
|
||||
* We must ensure this doesn't happen until the switch is completely
|
||||
* This must be the very last reference to @prev from this CPU. After
|
||||
* p->on_cpu is cleared, the task can be moved to a different CPU. We
|
||||
* must ensure this doesn't happen until the switch is completely
|
||||
* finished.
|
||||
*
|
||||
* In particular, the load of prev->state in finish_task_switch() must
|
||||
@ -3656,17 +3976,6 @@ unsigned long long task_sched_runtime(struct task_struct *p)
|
||||
return ns;
|
||||
}
|
||||
|
||||
DEFINE_PER_CPU(unsigned long, thermal_pressure);
|
||||
|
||||
void arch_set_thermal_pressure(struct cpumask *cpus,
|
||||
unsigned long th_pressure)
|
||||
{
|
||||
int cpu;
|
||||
|
||||
for_each_cpu(cpu, cpus)
|
||||
WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);
|
||||
}
|
||||
|
||||
/*
|
||||
* This function gets called by the timer code, with HZ frequency.
|
||||
* We call it with interrupts disabled.
|
||||
@ -4029,8 +4338,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
|
||||
* higher scheduling class, because otherwise those loose the
|
||||
* opportunity to pull in more work from other CPUs.
|
||||
*/
|
||||
if (likely((prev->sched_class == &idle_sched_class ||
|
||||
prev->sched_class == &fair_sched_class) &&
|
||||
if (likely(prev->sched_class <= &fair_sched_class &&
|
||||
rq->nr_running == rq->cfs.h_nr_running)) {
|
||||
|
||||
p = pick_next_task_fair(rq, prev, rf);
|
||||
@ -5519,6 +5827,11 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
|
||||
kattr.sched_nice = task_nice(p);
|
||||
|
||||
#ifdef CONFIG_UCLAMP_TASK
|
||||
/*
|
||||
* This could race with another potential updater, but this is fine
|
||||
* because it'll correctly read the old or the new value. We don't need
|
||||
* to guarantee who wins the race as long as it doesn't return garbage.
|
||||
*/
|
||||
kattr.sched_util_min = p->uclamp_req[UCLAMP_MIN].value;
|
||||
kattr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value;
|
||||
#endif
|
||||
@ -5876,7 +6189,7 @@ again:
|
||||
if (task_running(p_rq, p) || p->state)
|
||||
goto out_unlock;
|
||||
|
||||
yielded = curr->sched_class->yield_to_task(rq, p, preempt);
|
||||
yielded = curr->sched_class->yield_to_task(rq, p);
|
||||
if (yielded) {
|
||||
schedstat_inc(rq->yld_count);
|
||||
/*
|
||||
@ -6710,6 +7023,14 @@ void __init sched_init(void)
|
||||
unsigned long ptr = 0;
|
||||
int i;
|
||||
|
||||
/* Make sure the linker didn't screw up */
|
||||
BUG_ON(&idle_sched_class + 1 != &fair_sched_class ||
|
||||
&fair_sched_class + 1 != &rt_sched_class ||
|
||||
&rt_sched_class + 1 != &dl_sched_class);
|
||||
#ifdef CONFIG_SMP
|
||||
BUG_ON(&dl_sched_class + 1 != &stop_sched_class);
|
||||
#endif
|
||||
|
||||
wait_bit_init();
|
||||
|
||||
#ifdef CONFIG_FAIR_GROUP_SCHED
|
||||
@ -7431,6 +7752,8 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf,
|
||||
if (req.ret)
|
||||
return req.ret;
|
||||
|
||||
static_branch_enable(&sched_uclamp_used);
|
||||
|
||||
mutex_lock(&uclamp_mutex);
|
||||
rcu_read_lock();
|
||||
|
||||
@ -8118,4 +8441,7 @@ const u32 sched_prio_to_wmult[40] = {
|
||||
/* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
|
||||
};
|
||||
|
||||
#undef CREATE_TRACE_POINTS
|
||||
void call_trace_sched_update_nr_running(struct rq *rq, int count)
|
||||
{
|
||||
trace_sched_update_nr_running_tp(rq, count);
|
||||
}
|
||||
|
||||
@ -121,6 +121,30 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
|
||||
|
||||
if (later_mask &&
|
||||
cpumask_and(later_mask, cp->free_cpus, p->cpus_ptr)) {
|
||||
unsigned long cap, max_cap = 0;
|
||||
int cpu, max_cpu = -1;
|
||||
|
||||
if (!static_branch_unlikely(&sched_asym_cpucapacity))
|
||||
return 1;
|
||||
|
||||
/* Ensure the capacity of the CPUs fits the task. */
|
||||
for_each_cpu(cpu, later_mask) {
|
||||
if (!dl_task_fits_capacity(p, cpu)) {
|
||||
cpumask_clear_cpu(cpu, later_mask);
|
||||
|
||||
cap = capacity_orig_of(cpu);
|
||||
|
||||
if (cap > max_cap ||
|
||||
(cpu == task_cpu(p) && cap == max_cap)) {
|
||||
max_cap = cap;
|
||||
max_cpu = cpu;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (cpumask_empty(later_mask))
|
||||
cpumask_set_cpu(max_cpu, later_mask);
|
||||
|
||||
return 1;
|
||||
} else {
|
||||
int best_cpu = cpudl_maximum(cp);
|
||||
|
||||
@ -210,7 +210,7 @@ unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
|
||||
unsigned long dl_util, util, irq;
|
||||
struct rq *rq = cpu_rq(cpu);
|
||||
|
||||
if (!IS_BUILTIN(CONFIG_UCLAMP_TASK) &&
|
||||
if (!uclamp_is_used() &&
|
||||
type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) {
|
||||
return max;
|
||||
}
|
||||
|
||||
@ -519,50 +519,6 @@ void account_idle_ticks(unsigned long ticks)
|
||||
account_idle_time(cputime);
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform (stime * rtime) / total, but avoid multiplication overflow by
|
||||
* losing precision when the numbers are big.
|
||||
*/
|
||||
static u64 scale_stime(u64 stime, u64 rtime, u64 total)
|
||||
{
|
||||
u64 scaled;
|
||||
|
||||
for (;;) {
|
||||
/* Make sure "rtime" is the bigger of stime/rtime */
|
||||
if (stime > rtime)
|
||||
swap(rtime, stime);
|
||||
|
||||
/* Make sure 'total' fits in 32 bits */
|
||||
if (total >> 32)
|
||||
goto drop_precision;
|
||||
|
||||
/* Does rtime (and thus stime) fit in 32 bits? */
|
||||
if (!(rtime >> 32))
|
||||
break;
|
||||
|
||||
/* Can we just balance rtime/stime rather than dropping bits? */
|
||||
if (stime >> 31)
|
||||
goto drop_precision;
|
||||
|
||||
/* We can grow stime and shrink rtime and try to make them both fit */
|
||||
stime <<= 1;
|
||||
rtime >>= 1;
|
||||
continue;
|
||||
|
||||
drop_precision:
|
||||
/* We drop from rtime, it has more bits than stime */
|
||||
rtime >>= 1;
|
||||
total >>= 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Make sure gcc understands that this is a 32x32->64 multiply,
|
||||
* followed by a 64/32->64 divide.
|
||||
*/
|
||||
scaled = div_u64((u64) (u32) stime * (u64) (u32) rtime, (u32)total);
|
||||
return scaled;
|
||||
}
|
||||
|
||||
/*
|
||||
* Adjust tick based cputime random precision against scheduler runtime
|
||||
* accounting.
|
||||
@ -622,7 +578,7 @@ void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
|
||||
goto update;
|
||||
}
|
||||
|
||||
stime = scale_stime(stime, rtime, stime + utime);
|
||||
stime = mul_u64_u64_div_u64(stime, rtime, stime + utime);
|
||||
|
||||
update:
|
||||
/*
|
||||
|
||||
@ -54,15 +54,49 @@ static inline struct dl_bw *dl_bw_of(int i)
|
||||
static inline int dl_bw_cpus(int i)
|
||||
{
|
||||
struct root_domain *rd = cpu_rq(i)->rd;
|
||||
int cpus = 0;
|
||||
int cpus;
|
||||
|
||||
RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
|
||||
"sched RCU must be held");
|
||||
|
||||
if (cpumask_subset(rd->span, cpu_active_mask))
|
||||
return cpumask_weight(rd->span);
|
||||
|
||||
cpus = 0;
|
||||
|
||||
for_each_cpu_and(i, rd->span, cpu_active_mask)
|
||||
cpus++;
|
||||
|
||||
return cpus;
|
||||
}
|
||||
|
||||
static inline unsigned long __dl_bw_capacity(int i)
|
||||
{
|
||||
struct root_domain *rd = cpu_rq(i)->rd;
|
||||
unsigned long cap = 0;
|
||||
|
||||
RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
|
||||
"sched RCU must be held");
|
||||
|
||||
for_each_cpu_and(i, rd->span, cpu_active_mask)
|
||||
cap += capacity_orig_of(i);
|
||||
|
||||
return cap;
|
||||
}
|
||||
|
||||
/*
|
||||
* XXX Fix: If 'rq->rd == def_root_domain' perform AC against capacity
|
||||
* of the CPU the task is running on rather rd's \Sum CPU capacity.
|
||||
*/
|
||||
static inline unsigned long dl_bw_capacity(int i)
|
||||
{
|
||||
if (!static_branch_unlikely(&sched_asym_cpucapacity) &&
|
||||
capacity_orig_of(i) == SCHED_CAPACITY_SCALE) {
|
||||
return dl_bw_cpus(i) << SCHED_CAPACITY_SHIFT;
|
||||
} else {
|
||||
return __dl_bw_capacity(i);
|
||||
}
|
||||
}
|
||||
#else
|
||||
static inline struct dl_bw *dl_bw_of(int i)
|
||||
{
|
||||
@ -73,6 +107,11 @@ static inline int dl_bw_cpus(int i)
|
||||
{
|
||||
return 1;
|
||||
}
|
||||
|
||||
static inline unsigned long dl_bw_capacity(int i)
|
||||
{
|
||||
return SCHED_CAPACITY_SCALE;
|
||||
}
|
||||
#endif
|
||||
|
||||
static inline
|
||||
@ -1098,7 +1137,7 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
|
||||
* cannot use the runtime, and so it replenishes the task. This rule
|
||||
* works fine for implicit deadline tasks (deadline == period), and the
|
||||
* CBS was designed for implicit deadline tasks. However, a task with
|
||||
* constrained deadline (deadine < period) might be awakened after the
|
||||
* constrained deadline (deadline < period) might be awakened after the
|
||||
* deadline, but before the next period. In this case, replenishing the
|
||||
* task would allow it to run for runtime / deadline. As in this case
|
||||
* deadline < period, CBS enables a task to run for more than the
|
||||
@ -1604,6 +1643,7 @@ static int
|
||||
select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
|
||||
{
|
||||
struct task_struct *curr;
|
||||
bool select_rq;
|
||||
struct rq *rq;
|
||||
|
||||
if (sd_flag != SD_BALANCE_WAKE)
|
||||
@ -1623,10 +1663,19 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
|
||||
* other hand, if it has a shorter deadline, we
|
||||
* try to make it stay here, it might be important.
|
||||
*/
|
||||
if (unlikely(dl_task(curr)) &&
|
||||
(curr->nr_cpus_allowed < 2 ||
|
||||
!dl_entity_preempt(&p->dl, &curr->dl)) &&
|
||||
(p->nr_cpus_allowed > 1)) {
|
||||
select_rq = unlikely(dl_task(curr)) &&
|
||||
(curr->nr_cpus_allowed < 2 ||
|
||||
!dl_entity_preempt(&p->dl, &curr->dl)) &&
|
||||
p->nr_cpus_allowed > 1;
|
||||
|
||||
/*
|
||||
* Take the capacity of the CPU into account to
|
||||
* ensure it fits the requirement of the task.
|
||||
*/
|
||||
if (static_branch_unlikely(&sched_asym_cpucapacity))
|
||||
select_rq |= !dl_task_fits_capacity(p, cpu);
|
||||
|
||||
if (select_rq) {
|
||||
int target = find_later_rq(p);
|
||||
|
||||
if (target != -1 &&
|
||||
@ -2430,8 +2479,8 @@ static void prio_changed_dl(struct rq *rq, struct task_struct *p,
|
||||
}
|
||||
}
|
||||
|
||||
const struct sched_class dl_sched_class = {
|
||||
.next = &rt_sched_class,
|
||||
const struct sched_class dl_sched_class
|
||||
__attribute__((section("__dl_sched_class"))) = {
|
||||
.enqueue_task = enqueue_task_dl,
|
||||
.dequeue_task = dequeue_task_dl,
|
||||
.yield_task = yield_task_dl,
|
||||
@ -2551,11 +2600,12 @@ void sched_dl_do_global(void)
|
||||
int sched_dl_overflow(struct task_struct *p, int policy,
|
||||
const struct sched_attr *attr)
|
||||
{
|
||||
struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
|
||||
u64 period = attr->sched_period ?: attr->sched_deadline;
|
||||
u64 runtime = attr->sched_runtime;
|
||||
u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0;
|
||||
int cpus, err = -1;
|
||||
int cpus, err = -1, cpu = task_cpu(p);
|
||||
struct dl_bw *dl_b = dl_bw_of(cpu);
|
||||
unsigned long cap;
|
||||
|
||||
if (attr->sched_flags & SCHED_FLAG_SUGOV)
|
||||
return 0;
|
||||
@ -2570,15 +2620,17 @@ int sched_dl_overflow(struct task_struct *p, int policy,
|
||||
* allocated bandwidth of the container.
|
||||
*/
|
||||
raw_spin_lock(&dl_b->lock);
|
||||
cpus = dl_bw_cpus(task_cpu(p));
|
||||
cpus = dl_bw_cpus(cpu);
|
||||
cap = dl_bw_capacity(cpu);
|
||||
|
||||
if (dl_policy(policy) && !task_has_dl_policy(p) &&
|
||||
!__dl_overflow(dl_b, cpus, 0, new_bw)) {
|
||||
!__dl_overflow(dl_b, cap, 0, new_bw)) {
|
||||
if (hrtimer_active(&p->dl.inactive_timer))
|
||||
__dl_sub(dl_b, p->dl.dl_bw, cpus);
|
||||
__dl_add(dl_b, new_bw, cpus);
|
||||
err = 0;
|
||||
} else if (dl_policy(policy) && task_has_dl_policy(p) &&
|
||||
!__dl_overflow(dl_b, cpus, p->dl.dl_bw, new_bw)) {
|
||||
!__dl_overflow(dl_b, cap, p->dl.dl_bw, new_bw)) {
|
||||
/*
|
||||
* XXX this is slightly incorrect: when the task
|
||||
* utilization decreases, we should delay the total
|
||||
@ -2634,6 +2686,14 @@ void __getparam_dl(struct task_struct *p, struct sched_attr *attr)
|
||||
attr->sched_flags = dl_se->flags;
|
||||
}
|
||||
|
||||
/*
|
||||
* Default limits for DL period; on the top end we guard against small util
|
||||
* tasks still getting rediculous long effective runtimes, on the bottom end we
|
||||
* guard against timer DoS.
|
||||
*/
|
||||
unsigned int sysctl_sched_dl_period_max = 1 << 22; /* ~4 seconds */
|
||||
unsigned int sysctl_sched_dl_period_min = 100; /* 100 us */
|
||||
|
||||
/*
|
||||
* This function validates the new parameters of a -deadline task.
|
||||
* We ask for the deadline not being zero, and greater or equal
|
||||
@ -2646,6 +2706,8 @@ void __getparam_dl(struct task_struct *p, struct sched_attr *attr)
|
||||
*/
|
||||
bool __checkparam_dl(const struct sched_attr *attr)
|
||||
{
|
||||
u64 period, max, min;
|
||||
|
||||
/* special dl tasks don't actually use any parameter */
|
||||
if (attr->sched_flags & SCHED_FLAG_SUGOV)
|
||||
return true;
|
||||
@ -2669,12 +2731,21 @@ bool __checkparam_dl(const struct sched_attr *attr)
|
||||
attr->sched_period & (1ULL << 63))
|
||||
return false;
|
||||
|
||||
period = attr->sched_period;
|
||||
if (!period)
|
||||
period = attr->sched_deadline;
|
||||
|
||||
/* runtime <= deadline <= period (if period != 0) */
|
||||
if ((attr->sched_period != 0 &&
|
||||
attr->sched_period < attr->sched_deadline) ||
|
||||
if (period < attr->sched_deadline ||
|
||||
attr->sched_deadline < attr->sched_runtime)
|
||||
return false;
|
||||
|
||||
max = (u64)READ_ONCE(sysctl_sched_dl_period_max) * NSEC_PER_USEC;
|
||||
min = (u64)READ_ONCE(sysctl_sched_dl_period_min) * NSEC_PER_USEC;
|
||||
|
||||
if (period < min || period > max)
|
||||
return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
@ -2715,19 +2786,19 @@ bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)
|
||||
#ifdef CONFIG_SMP
|
||||
int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed)
|
||||
{
|
||||
unsigned long flags, cap;
|
||||
unsigned int dest_cpu;
|
||||
struct dl_bw *dl_b;
|
||||
bool overflow;
|
||||
int cpus, ret;
|
||||
unsigned long flags;
|
||||
int ret;
|
||||
|
||||
dest_cpu = cpumask_any_and(cpu_active_mask, cs_cpus_allowed);
|
||||
|
||||
rcu_read_lock_sched();
|
||||
dl_b = dl_bw_of(dest_cpu);
|
||||
raw_spin_lock_irqsave(&dl_b->lock, flags);
|
||||
cpus = dl_bw_cpus(dest_cpu);
|
||||
overflow = __dl_overflow(dl_b, cpus, 0, p->dl.dl_bw);
|
||||
cap = dl_bw_capacity(dest_cpu);
|
||||
overflow = __dl_overflow(dl_b, cap, 0, p->dl.dl_bw);
|
||||
if (overflow) {
|
||||
ret = -EBUSY;
|
||||
} else {
|
||||
@ -2737,6 +2808,8 @@ int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allo
|
||||
* We will free resources in the source root_domain
|
||||
* later on (see set_cpus_allowed_dl()).
|
||||
*/
|
||||
int cpus = dl_bw_cpus(dest_cpu);
|
||||
|
||||
__dl_add(dl_b, p->dl.dl_bw, cpus);
|
||||
ret = 0;
|
||||
}
|
||||
@ -2769,16 +2842,15 @@ int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur,
|
||||
|
||||
bool dl_cpu_busy(unsigned int cpu)
|
||||
{
|
||||
unsigned long flags;
|
||||
unsigned long flags, cap;
|
||||
struct dl_bw *dl_b;
|
||||
bool overflow;
|
||||
int cpus;
|
||||
|
||||
rcu_read_lock_sched();
|
||||
dl_b = dl_bw_of(cpu);
|
||||
raw_spin_lock_irqsave(&dl_b->lock, flags);
|
||||
cpus = dl_bw_cpus(cpu);
|
||||
overflow = __dl_overflow(dl_b, cpus, 0, 0);
|
||||
cap = dl_bw_capacity(cpu);
|
||||
overflow = __dl_overflow(dl_b, cap, 0, 0);
|
||||
raw_spin_unlock_irqrestore(&dl_b->lock, flags);
|
||||
rcu_read_unlock_sched();
|
||||
|
||||
|
||||
@ -22,8 +22,6 @@
|
||||
*/
|
||||
#include "sched.h"
|
||||
|
||||
#include <trace/events/sched.h>
|
||||
|
||||
/*
|
||||
* Targeted preemption latency for CPU-bound tasks:
|
||||
*
|
||||
@ -3094,7 +3092,7 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
do {
|
||||
u32 divider = LOAD_AVG_MAX - 1024 + se->avg.period_contrib;
|
||||
u32 divider = get_pelt_divider(&se->avg);
|
||||
|
||||
se->avg.load_avg = div_u64(se_weight(se) * se->avg.load_sum, divider);
|
||||
} while (0);
|
||||
@ -3440,16 +3438,18 @@ static inline void
|
||||
update_tg_cfs_util(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq *gcfs_rq)
|
||||
{
|
||||
long delta = gcfs_rq->avg.util_avg - se->avg.util_avg;
|
||||
/*
|
||||
* cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
|
||||
* See ___update_load_avg() for details.
|
||||
*/
|
||||
u32 divider = LOAD_AVG_MAX - 1024 + cfs_rq->avg.period_contrib;
|
||||
u32 divider;
|
||||
|
||||
/* Nothing to update */
|
||||
if (!delta)
|
||||
return;
|
||||
|
||||
/*
|
||||
* cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
|
||||
* See ___update_load_avg() for details.
|
||||
*/
|
||||
divider = get_pelt_divider(&cfs_rq->avg);
|
||||
|
||||
/* Set new sched_entity's utilization */
|
||||
se->avg.util_avg = gcfs_rq->avg.util_avg;
|
||||
se->avg.util_sum = se->avg.util_avg * divider;
|
||||
@ -3463,16 +3463,18 @@ static inline void
|
||||
update_tg_cfs_runnable(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq *gcfs_rq)
|
||||
{
|
||||
long delta = gcfs_rq->avg.runnable_avg - se->avg.runnable_avg;
|
||||
/*
|
||||
* cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
|
||||
* See ___update_load_avg() for details.
|
||||
*/
|
||||
u32 divider = LOAD_AVG_MAX - 1024 + cfs_rq->avg.period_contrib;
|
||||
u32 divider;
|
||||
|
||||
/* Nothing to update */
|
||||
if (!delta)
|
||||
return;
|
||||
|
||||
/*
|
||||
* cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
|
||||
* See ___update_load_avg() for details.
|
||||
*/
|
||||
divider = get_pelt_divider(&cfs_rq->avg);
|
||||
|
||||
/* Set new sched_entity's runnable */
|
||||
se->avg.runnable_avg = gcfs_rq->avg.runnable_avg;
|
||||
se->avg.runnable_sum = se->avg.runnable_avg * divider;
|
||||
@ -3500,7 +3502,7 @@ update_tg_cfs_load(struct cfs_rq *cfs_rq, struct sched_entity *se, struct cfs_rq
|
||||
* cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
|
||||
* See ___update_load_avg() for details.
|
||||
*/
|
||||
divider = LOAD_AVG_MAX - 1024 + cfs_rq->avg.period_contrib;
|
||||
divider = get_pelt_divider(&cfs_rq->avg);
|
||||
|
||||
if (runnable_sum >= 0) {
|
||||
/*
|
||||
@ -3646,7 +3648,7 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
|
||||
|
||||
if (cfs_rq->removed.nr) {
|
||||
unsigned long r;
|
||||
u32 divider = LOAD_AVG_MAX - 1024 + sa->period_contrib;
|
||||
u32 divider = get_pelt_divider(&cfs_rq->avg);
|
||||
|
||||
raw_spin_lock(&cfs_rq->removed.lock);
|
||||
swap(cfs_rq->removed.util_avg, removed_util);
|
||||
@ -3701,7 +3703,7 @@ static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s
|
||||
* cfs_rq->avg.period_contrib can be used for both cfs_rq and se.
|
||||
* See ___update_load_avg() for details.
|
||||
*/
|
||||
u32 divider = LOAD_AVG_MAX - 1024 + cfs_rq->avg.period_contrib;
|
||||
u32 divider = get_pelt_divider(&cfs_rq->avg);
|
||||
|
||||
/*
|
||||
* When we attach the @se to the @cfs_rq, we must align the decay
|
||||
@ -3922,6 +3924,8 @@ static inline void util_est_enqueue(struct cfs_rq *cfs_rq,
|
||||
enqueued = cfs_rq->avg.util_est.enqueued;
|
||||
enqueued += _task_util_est(p);
|
||||
WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued);
|
||||
|
||||
trace_sched_util_est_cfs_tp(cfs_rq);
|
||||
}
|
||||
|
||||
/*
|
||||
@ -3952,6 +3956,8 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep)
|
||||
ue.enqueued -= min_t(unsigned int, ue.enqueued, _task_util_est(p));
|
||||
WRITE_ONCE(cfs_rq->avg.util_est.enqueued, ue.enqueued);
|
||||
|
||||
trace_sched_util_est_cfs_tp(cfs_rq);
|
||||
|
||||
/*
|
||||
* Skip update of task's estimated utilization when the task has not
|
||||
* yet completed an activation, e.g. being migrated.
|
||||
@ -4017,6 +4023,8 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep)
|
||||
ue.ewma >>= UTIL_EST_WEIGHT_SHIFT;
|
||||
done:
|
||||
WRITE_ONCE(p->se.avg.util_est, ue);
|
||||
|
||||
trace_sched_util_est_se_tp(&p->se);
|
||||
}
|
||||
|
||||
static inline int task_fits_capacity(struct task_struct *p, long capacity)
|
||||
@ -5618,14 +5626,14 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
|
||||
|
||||
}
|
||||
|
||||
dequeue_throttle:
|
||||
if (!se)
|
||||
sub_nr_running(rq, 1);
|
||||
/* At this point se is NULL and we are at root level*/
|
||||
sub_nr_running(rq, 1);
|
||||
|
||||
/* balance early to pull high priority tasks */
|
||||
if (unlikely(!was_sched_idle && sched_idle_rq(rq)))
|
||||
rq->next_balance = jiffies;
|
||||
|
||||
dequeue_throttle:
|
||||
util_est_dequeue(&rq->cfs, p, task_sleep);
|
||||
hrtick_update(rq);
|
||||
}
|
||||
@ -7161,7 +7169,7 @@ static void yield_task_fair(struct rq *rq)
|
||||
set_skip_buddy(se);
|
||||
}
|
||||
|
||||
static bool yield_to_task_fair(struct rq *rq, struct task_struct *p, bool preempt)
|
||||
static bool yield_to_task_fair(struct rq *rq, struct task_struct *p)
|
||||
{
|
||||
struct sched_entity *se = &p->se;
|
||||
|
||||
@ -8049,7 +8057,7 @@ static inline void init_sd_lb_stats(struct sd_lb_stats *sds)
|
||||
};
|
||||
}
|
||||
|
||||
static unsigned long scale_rt_capacity(struct sched_domain *sd, int cpu)
|
||||
static unsigned long scale_rt_capacity(int cpu)
|
||||
{
|
||||
struct rq *rq = cpu_rq(cpu);
|
||||
unsigned long max = arch_scale_cpu_capacity(cpu);
|
||||
@ -8081,7 +8089,7 @@ static unsigned long scale_rt_capacity(struct sched_domain *sd, int cpu)
|
||||
|
||||
static void update_cpu_capacity(struct sched_domain *sd, int cpu)
|
||||
{
|
||||
unsigned long capacity = scale_rt_capacity(sd, cpu);
|
||||
unsigned long capacity = scale_rt_capacity(cpu);
|
||||
struct sched_group *sdg = sd->groups;
|
||||
|
||||
cpu_rq(cpu)->cpu_capacity_orig = arch_scale_cpu_capacity(cpu);
|
||||
@ -8703,8 +8711,14 @@ static bool update_pick_idlest(struct sched_group *idlest,
|
||||
|
||||
case group_has_spare:
|
||||
/* Select group with most idle CPUs */
|
||||
if (idlest_sgs->idle_cpus >= sgs->idle_cpus)
|
||||
if (idlest_sgs->idle_cpus > sgs->idle_cpus)
|
||||
return false;
|
||||
|
||||
/* Select group with lowest group_util */
|
||||
if (idlest_sgs->idle_cpus == sgs->idle_cpus &&
|
||||
idlest_sgs->group_util <= sgs->group_util)
|
||||
return false;
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
@ -10027,7 +10041,12 @@ static void kick_ilb(unsigned int flags)
|
||||
{
|
||||
int ilb_cpu;
|
||||
|
||||
nohz.next_balance++;
|
||||
/*
|
||||
* Increase nohz.next_balance only when if full ilb is triggered but
|
||||
* not if we only update stats.
|
||||
*/
|
||||
if (flags & NOHZ_BALANCE_KICK)
|
||||
nohz.next_balance = jiffies+1;
|
||||
|
||||
ilb_cpu = find_new_ilb();
|
||||
|
||||
@ -10348,6 +10367,14 @@ static bool _nohz_idle_balance(struct rq *this_rq, unsigned int flags,
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* next_balance will be updated only when there is a need.
|
||||
* When the CPU is attached to null domain for ex, it will not be
|
||||
* updated.
|
||||
*/
|
||||
if (likely(update_next_balance))
|
||||
nohz.next_balance = next_balance;
|
||||
|
||||
/* Newly idle CPU doesn't need an update */
|
||||
if (idle != CPU_NEWLY_IDLE) {
|
||||
update_blocked_averages(this_cpu);
|
||||
@ -10368,14 +10395,6 @@ abort:
|
||||
if (has_blocked_load)
|
||||
WRITE_ONCE(nohz.has_blocked, 1);
|
||||
|
||||
/*
|
||||
* next_balance will be updated only when there is a need.
|
||||
* When the CPU is attached to null domain for ex, it will not be
|
||||
* updated.
|
||||
*/
|
||||
if (likely(update_next_balance))
|
||||
nohz.next_balance = next_balance;
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
@ -11118,8 +11137,8 @@ static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task
|
||||
/*
|
||||
* All the scheduling class methods:
|
||||
*/
|
||||
const struct sched_class fair_sched_class = {
|
||||
.next = &idle_sched_class,
|
||||
const struct sched_class fair_sched_class
|
||||
__attribute__((section("__fair_sched_class"))) = {
|
||||
.enqueue_task = enqueue_task_fair,
|
||||
.dequeue_task = dequeue_task_fair,
|
||||
.yield_task = yield_task_fair,
|
||||
@ -11292,3 +11311,9 @@ const struct cpumask *sched_trace_rd_span(struct root_domain *rd)
|
||||
#endif
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(sched_trace_rd_span);
|
||||
|
||||
int sched_trace_rq_nr_running(struct rq *rq)
|
||||
{
|
||||
return rq ? rq->nr_running : -1;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(sched_trace_rq_nr_running);
|
||||
|
||||
@ -453,11 +453,6 @@ prio_changed_idle(struct rq *rq, struct task_struct *p, int oldprio)
|
||||
BUG();
|
||||
}
|
||||
|
||||
static unsigned int get_rr_interval_idle(struct rq *rq, struct task_struct *task)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void update_curr_idle(struct rq *rq)
|
||||
{
|
||||
}
|
||||
@ -465,8 +460,8 @@ static void update_curr_idle(struct rq *rq)
|
||||
/*
|
||||
* Simple, special scheduling class for the per-CPU idle tasks:
|
||||
*/
|
||||
const struct sched_class idle_sched_class = {
|
||||
/* .next is NULL */
|
||||
const struct sched_class idle_sched_class
|
||||
__attribute__((section("__idle_sched_class"))) = {
|
||||
/* no enqueue/yield_task for idle tasks */
|
||||
|
||||
/* dequeue is not valid, we print a debug message there: */
|
||||
@ -486,8 +481,6 @@ const struct sched_class idle_sched_class = {
|
||||
|
||||
.task_tick = task_tick_idle,
|
||||
|
||||
.get_rr_interval = get_rr_interval_idle,
|
||||
|
||||
.prio_changed = prio_changed_idle,
|
||||
.switched_to = switched_to_idle,
|
||||
.update_curr = update_curr_idle,
|
||||
|
||||
@ -140,7 +140,8 @@ static int __init housekeeping_nohz_full_setup(char *str)
|
||||
{
|
||||
unsigned int flags;
|
||||
|
||||
flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU | HK_FLAG_MISC;
|
||||
flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU |
|
||||
HK_FLAG_MISC | HK_FLAG_KTHREAD;
|
||||
|
||||
return housekeeping_setup(str, flags);
|
||||
}
|
||||
|
||||
@ -347,7 +347,7 @@ static inline void calc_global_nohz(void) { }
|
||||
*
|
||||
* Called from the global timer code.
|
||||
*/
|
||||
void calc_global_load(unsigned long ticks)
|
||||
void calc_global_load(void)
|
||||
{
|
||||
unsigned long sample_window;
|
||||
long active, delta;
|
||||
|
||||
@ -28,8 +28,6 @@
|
||||
#include "sched.h"
|
||||
#include "pelt.h"
|
||||
|
||||
#include <trace/events/sched.h>
|
||||
|
||||
/*
|
||||
* Approximate:
|
||||
* val * y^n, where y^32 ~= 0.5 (~1 scheduling period)
|
||||
@ -83,8 +81,6 @@ static u32 __accumulate_pelt_segments(u64 periods, u32 d1, u32 d3)
|
||||
return c1 + c2 + c3;
|
||||
}
|
||||
|
||||
#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
|
||||
|
||||
/*
|
||||
* Accumulate the three separate parts of the sum; d1 the remainder
|
||||
* of the last (incomplete) period, d2 the span of full periods and d3
|
||||
@ -264,7 +260,7 @@ ___update_load_sum(u64 now, struct sched_avg *sa,
|
||||
static __always_inline void
|
||||
___update_load_avg(struct sched_avg *sa, unsigned long load)
|
||||
{
|
||||
u32 divider = LOAD_AVG_MAX - 1024 + sa->period_contrib;
|
||||
u32 divider = get_pelt_divider(sa);
|
||||
|
||||
/*
|
||||
* Step 2: update *_avg.
|
||||
|
||||
@ -37,6 +37,11 @@ update_irq_load_avg(struct rq *rq, u64 running)
|
||||
}
|
||||
#endif
|
||||
|
||||
static inline u32 get_pelt_divider(struct sched_avg *avg)
|
||||
{
|
||||
return LOAD_AVG_MAX - 1024 + avg->period_contrib;
|
||||
}
|
||||
|
||||
/*
|
||||
* When a task is dequeued, its estimated utilization should not be update if
|
||||
* its util_avg has not been updated at least once.
|
||||
|
||||
@ -190,7 +190,6 @@ static void group_init(struct psi_group *group)
|
||||
INIT_DELAYED_WORK(&group->avgs_work, psi_avgs_work);
|
||||
mutex_init(&group->avgs_lock);
|
||||
/* Init trigger-related members */
|
||||
atomic_set(&group->poll_scheduled, 0);
|
||||
mutex_init(&group->trigger_lock);
|
||||
INIT_LIST_HEAD(&group->triggers);
|
||||
memset(group->nr_triggers, 0, sizeof(group->nr_triggers));
|
||||
@ -199,7 +198,7 @@ static void group_init(struct psi_group *group)
|
||||
memset(group->polling_total, 0, sizeof(group->polling_total));
|
||||
group->polling_next_update = ULLONG_MAX;
|
||||
group->polling_until = 0;
|
||||
rcu_assign_pointer(group->poll_kworker, NULL);
|
||||
rcu_assign_pointer(group->poll_task, NULL);
|
||||
}
|
||||
|
||||
void __init psi_init(void)
|
||||
@ -547,47 +546,38 @@ static u64 update_triggers(struct psi_group *group, u64 now)
|
||||
return now + group->poll_min_period;
|
||||
}
|
||||
|
||||
/*
|
||||
* Schedule polling if it's not already scheduled. It's safe to call even from
|
||||
* hotpath because even though kthread_queue_delayed_work takes worker->lock
|
||||
* spinlock that spinlock is never contended due to poll_scheduled atomic
|
||||
* preventing such competition.
|
||||
*/
|
||||
/* Schedule polling if it's not already scheduled. */
|
||||
static void psi_schedule_poll_work(struct psi_group *group, unsigned long delay)
|
||||
{
|
||||
struct kthread_worker *kworker;
|
||||
struct task_struct *task;
|
||||
|
||||
/* Do not reschedule if already scheduled */
|
||||
if (atomic_cmpxchg(&group->poll_scheduled, 0, 1) != 0)
|
||||
/*
|
||||
* Do not reschedule if already scheduled.
|
||||
* Possible race with a timer scheduled after this check but before
|
||||
* mod_timer below can be tolerated because group->polling_next_update
|
||||
* will keep updates on schedule.
|
||||
*/
|
||||
if (timer_pending(&group->poll_timer))
|
||||
return;
|
||||
|
||||
rcu_read_lock();
|
||||
|
||||
kworker = rcu_dereference(group->poll_kworker);
|
||||
task = rcu_dereference(group->poll_task);
|
||||
/*
|
||||
* kworker might be NULL in case psi_trigger_destroy races with
|
||||
* psi_task_change (hotpath) which can't use locks
|
||||
*/
|
||||
if (likely(kworker))
|
||||
kthread_queue_delayed_work(kworker, &group->poll_work, delay);
|
||||
else
|
||||
atomic_set(&group->poll_scheduled, 0);
|
||||
if (likely(task))
|
||||
mod_timer(&group->poll_timer, jiffies + delay);
|
||||
|
||||
rcu_read_unlock();
|
||||
}
|
||||
|
||||
static void psi_poll_work(struct kthread_work *work)
|
||||
static void psi_poll_work(struct psi_group *group)
|
||||
{
|
||||
struct kthread_delayed_work *dwork;
|
||||
struct psi_group *group;
|
||||
u32 changed_states;
|
||||
u64 now;
|
||||
|
||||
dwork = container_of(work, struct kthread_delayed_work, work);
|
||||
group = container_of(dwork, struct psi_group, poll_work);
|
||||
|
||||
atomic_set(&group->poll_scheduled, 0);
|
||||
|
||||
mutex_lock(&group->trigger_lock);
|
||||
|
||||
now = sched_clock();
|
||||
@ -623,6 +613,35 @@ out:
|
||||
mutex_unlock(&group->trigger_lock);
|
||||
}
|
||||
|
||||
static int psi_poll_worker(void *data)
|
||||
{
|
||||
struct psi_group *group = (struct psi_group *)data;
|
||||
struct sched_param param = {
|
||||
.sched_priority = 1,
|
||||
};
|
||||
|
||||
sched_setscheduler_nocheck(current, SCHED_FIFO, ¶m);
|
||||
|
||||
while (true) {
|
||||
wait_event_interruptible(group->poll_wait,
|
||||
atomic_cmpxchg(&group->poll_wakeup, 1, 0) ||
|
||||
kthread_should_stop());
|
||||
if (kthread_should_stop())
|
||||
break;
|
||||
|
||||
psi_poll_work(group);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void poll_timer_fn(struct timer_list *t)
|
||||
{
|
||||
struct psi_group *group = from_timer(group, t, poll_timer);
|
||||
|
||||
atomic_set(&group->poll_wakeup, 1);
|
||||
wake_up_interruptible(&group->poll_wait);
|
||||
}
|
||||
|
||||
static void record_times(struct psi_group_cpu *groupc, int cpu,
|
||||
bool memstall_tick)
|
||||
{
|
||||
@ -1099,22 +1118,20 @@ struct psi_trigger *psi_trigger_create(struct psi_group *group,
|
||||
|
||||
mutex_lock(&group->trigger_lock);
|
||||
|
||||
if (!rcu_access_pointer(group->poll_kworker)) {
|
||||
struct sched_param param = {
|
||||
.sched_priority = 1,
|
||||
};
|
||||
struct kthread_worker *kworker;
|
||||
if (!rcu_access_pointer(group->poll_task)) {
|
||||
struct task_struct *task;
|
||||
|
||||
kworker = kthread_create_worker(0, "psimon");
|
||||
if (IS_ERR(kworker)) {
|
||||
task = kthread_create(psi_poll_worker, group, "psimon");
|
||||
if (IS_ERR(task)) {
|
||||
kfree(t);
|
||||
mutex_unlock(&group->trigger_lock);
|
||||
return ERR_CAST(kworker);
|
||||
return ERR_CAST(task);
|
||||
}
|
||||
sched_setscheduler_nocheck(kworker->task, SCHED_FIFO, ¶m);
|
||||
kthread_init_delayed_work(&group->poll_work,
|
||||
psi_poll_work);
|
||||
rcu_assign_pointer(group->poll_kworker, kworker);
|
||||
atomic_set(&group->poll_wakeup, 0);
|
||||
init_waitqueue_head(&group->poll_wait);
|
||||
wake_up_process(task);
|
||||
timer_setup(&group->poll_timer, poll_timer_fn, 0);
|
||||
rcu_assign_pointer(group->poll_task, task);
|
||||
}
|
||||
|
||||
list_add(&t->node, &group->triggers);
|
||||
@ -1132,7 +1149,7 @@ static void psi_trigger_destroy(struct kref *ref)
|
||||
{
|
||||
struct psi_trigger *t = container_of(ref, struct psi_trigger, refcount);
|
||||
struct psi_group *group = t->group;
|
||||
struct kthread_worker *kworker_to_destroy = NULL;
|
||||
struct task_struct *task_to_destroy = NULL;
|
||||
|
||||
if (static_branch_likely(&psi_disabled))
|
||||
return;
|
||||
@ -1158,13 +1175,13 @@ static void psi_trigger_destroy(struct kref *ref)
|
||||
period = min(period, div_u64(tmp->win.size,
|
||||
UPDATES_PER_WINDOW));
|
||||
group->poll_min_period = period;
|
||||
/* Destroy poll_kworker when the last trigger is destroyed */
|
||||
/* Destroy poll_task when the last trigger is destroyed */
|
||||
if (group->poll_states == 0) {
|
||||
group->polling_until = 0;
|
||||
kworker_to_destroy = rcu_dereference_protected(
|
||||
group->poll_kworker,
|
||||
task_to_destroy = rcu_dereference_protected(
|
||||
group->poll_task,
|
||||
lockdep_is_held(&group->trigger_lock));
|
||||
rcu_assign_pointer(group->poll_kworker, NULL);
|
||||
rcu_assign_pointer(group->poll_task, NULL);
|
||||
}
|
||||
}
|
||||
|
||||
@ -1172,25 +1189,23 @@ static void psi_trigger_destroy(struct kref *ref)
|
||||
|
||||
/*
|
||||
* Wait for both *trigger_ptr from psi_trigger_replace and
|
||||
* poll_kworker RCUs to complete their read-side critical sections
|
||||
* before destroying the trigger and optionally the poll_kworker
|
||||
* poll_task RCUs to complete their read-side critical sections
|
||||
* before destroying the trigger and optionally the poll_task
|
||||
*/
|
||||
synchronize_rcu();
|
||||
/*
|
||||
* Destroy the kworker after releasing trigger_lock to prevent a
|
||||
* deadlock while waiting for psi_poll_work to acquire trigger_lock
|
||||
*/
|
||||
if (kworker_to_destroy) {
|
||||
if (task_to_destroy) {
|
||||
/*
|
||||
* After the RCU grace period has expired, the worker
|
||||
* can no longer be found through group->poll_kworker.
|
||||
* can no longer be found through group->poll_task.
|
||||
* But it might have been already scheduled before
|
||||
* that - deschedule it cleanly before destroying it.
|
||||
*/
|
||||
kthread_cancel_delayed_work_sync(&group->poll_work);
|
||||
atomic_set(&group->poll_scheduled, 0);
|
||||
|
||||
kthread_destroy_worker(kworker_to_destroy);
|
||||
del_timer_sync(&group->poll_timer);
|
||||
kthread_stop(task_to_destroy);
|
||||
}
|
||||
kfree(t);
|
||||
}
|
||||
|
||||
@ -2429,8 +2429,8 @@ static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
|
||||
return 0;
|
||||
}
|
||||
|
||||
const struct sched_class rt_sched_class = {
|
||||
.next = &fair_sched_class,
|
||||
const struct sched_class rt_sched_class
|
||||
__attribute__((section("__rt_sched_class"))) = {
|
||||
.enqueue_task = enqueue_task_rt,
|
||||
.dequeue_task = dequeue_task_rt,
|
||||
.yield_task = yield_task_rt,
|
||||
|
||||
@ -67,6 +67,7 @@
|
||||
#include <linux/tsacct_kern.h>
|
||||
|
||||
#include <asm/tlb.h>
|
||||
#include <asm-generic/vmlinux.lds.h>
|
||||
|
||||
#ifdef CONFIG_PARAVIRT
|
||||
# include <asm/paravirt.h>
|
||||
@ -75,6 +76,8 @@
|
||||
#include "cpupri.h"
|
||||
#include "cpudeadline.h"
|
||||
|
||||
#include <trace/events/sched.h>
|
||||
|
||||
#ifdef CONFIG_SCHED_DEBUG
|
||||
# define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
|
||||
#else
|
||||
@ -96,6 +99,7 @@ extern atomic_long_t calc_load_tasks;
|
||||
extern void calc_global_load_tick(struct rq *this_rq);
|
||||
extern long calc_load_fold_active(struct rq *this_rq, long adjust);
|
||||
|
||||
extern void call_trace_sched_update_nr_running(struct rq *rq, int count);
|
||||
/*
|
||||
* Helpers for converting nanosecond timing to jiffy resolution
|
||||
*/
|
||||
@ -310,11 +314,26 @@ void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
|
||||
__dl_update(dl_b, -((s32)tsk_bw / cpus));
|
||||
}
|
||||
|
||||
static inline
|
||||
bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
|
||||
static inline bool __dl_overflow(struct dl_bw *dl_b, unsigned long cap,
|
||||
u64 old_bw, u64 new_bw)
|
||||
{
|
||||
return dl_b->bw != -1 &&
|
||||
dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
|
||||
cap_scale(dl_b->bw, cap) < dl_b->total_bw - old_bw + new_bw;
|
||||
}
|
||||
|
||||
/*
|
||||
* Verify the fitness of task @p to run on @cpu taking into account the
|
||||
* CPU original capacity and the runtime/deadline ratio of the task.
|
||||
*
|
||||
* The function will return true if the CPU original capacity of the
|
||||
* @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the
|
||||
* task and false otherwise.
|
||||
*/
|
||||
static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu)
|
||||
{
|
||||
unsigned long cap = arch_scale_cpu_capacity(cpu);
|
||||
|
||||
return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime;
|
||||
}
|
||||
|
||||
extern void init_dl_bw(struct dl_bw *dl_b);
|
||||
@ -862,6 +881,8 @@ struct uclamp_rq {
|
||||
unsigned int value;
|
||||
struct uclamp_bucket bucket[UCLAMP_BUCKETS];
|
||||
};
|
||||
|
||||
DECLARE_STATIC_KEY_FALSE(sched_uclamp_used);
|
||||
#endif /* CONFIG_UCLAMP_TASK */
|
||||
|
||||
/*
|
||||
@ -1182,6 +1203,16 @@ struct rq_flags {
|
||||
#endif
|
||||
};
|
||||
|
||||
/*
|
||||
* Lockdep annotation that avoids accidental unlocks; it's like a
|
||||
* sticky/continuous lockdep_assert_held().
|
||||
*
|
||||
* This avoids code that has access to 'struct rq *rq' (basically everything in
|
||||
* the scheduler) from accidentally unlocking the rq if they do not also have a
|
||||
* copy of the (on-stack) 'struct rq_flags rf'.
|
||||
*
|
||||
* Also see Documentation/locking/lockdep-design.rst.
|
||||
*/
|
||||
static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
|
||||
{
|
||||
rf->cookie = lockdep_pin_lock(&rq->lock);
|
||||
@ -1739,7 +1770,6 @@ extern const u32 sched_prio_to_wmult[40];
|
||||
#define RETRY_TASK ((void *)-1UL)
|
||||
|
||||
struct sched_class {
|
||||
const struct sched_class *next;
|
||||
|
||||
#ifdef CONFIG_UCLAMP_TASK
|
||||
int uclamp_enabled;
|
||||
@ -1748,7 +1778,7 @@ struct sched_class {
|
||||
void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
|
||||
void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
|
||||
void (*yield_task) (struct rq *rq);
|
||||
bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
|
||||
bool (*yield_to_task)(struct rq *rq, struct task_struct *p);
|
||||
|
||||
void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
|
||||
|
||||
@ -1796,7 +1826,7 @@ struct sched_class {
|
||||
#ifdef CONFIG_FAIR_GROUP_SCHED
|
||||
void (*task_change_group)(struct task_struct *p, int type);
|
||||
#endif
|
||||
};
|
||||
} __aligned(STRUCT_ALIGNMENT); /* STRUCT_ALIGN(), vmlinux.lds.h */
|
||||
|
||||
static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
|
||||
{
|
||||
@ -1810,17 +1840,18 @@ static inline void set_next_task(struct rq *rq, struct task_struct *next)
|
||||
next->sched_class->set_next_task(rq, next, false);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
#define sched_class_highest (&stop_sched_class)
|
||||
#else
|
||||
#define sched_class_highest (&dl_sched_class)
|
||||
#endif
|
||||
/* Defined in include/asm-generic/vmlinux.lds.h */
|
||||
extern struct sched_class __begin_sched_classes[];
|
||||
extern struct sched_class __end_sched_classes[];
|
||||
|
||||
#define sched_class_highest (__end_sched_classes - 1)
|
||||
#define sched_class_lowest (__begin_sched_classes - 1)
|
||||
|
||||
#define for_class_range(class, _from, _to) \
|
||||
for (class = (_from); class != (_to); class = class->next)
|
||||
for (class = (_from); class != (_to); class--)
|
||||
|
||||
#define for_each_class(class) \
|
||||
for_class_range(class, sched_class_highest, NULL)
|
||||
for_class_range(class, sched_class_highest, sched_class_lowest)
|
||||
|
||||
extern const struct sched_class stop_sched_class;
|
||||
extern const struct sched_class dl_sched_class;
|
||||
@ -1930,12 +1961,7 @@ extern int __init sched_tick_offload_init(void);
|
||||
*/
|
||||
static inline void sched_update_tick_dependency(struct rq *rq)
|
||||
{
|
||||
int cpu;
|
||||
|
||||
if (!tick_nohz_full_enabled())
|
||||
return;
|
||||
|
||||
cpu = cpu_of(rq);
|
||||
int cpu = cpu_of(rq);
|
||||
|
||||
if (!tick_nohz_full_cpu(cpu))
|
||||
return;
|
||||
@ -1955,6 +1981,9 @@ static inline void add_nr_running(struct rq *rq, unsigned count)
|
||||
unsigned prev_nr = rq->nr_running;
|
||||
|
||||
rq->nr_running = prev_nr + count;
|
||||
if (trace_sched_update_nr_running_tp_enabled()) {
|
||||
call_trace_sched_update_nr_running(rq, count);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
if (prev_nr < 2 && rq->nr_running >= 2) {
|
||||
@ -1969,6 +1998,10 @@ static inline void add_nr_running(struct rq *rq, unsigned count)
|
||||
static inline void sub_nr_running(struct rq *rq, unsigned count)
|
||||
{
|
||||
rq->nr_running -= count;
|
||||
if (trace_sched_update_nr_running_tp_enabled()) {
|
||||
call_trace_sched_update_nr_running(rq, count);
|
||||
}
|
||||
|
||||
/* Check if we still need preemption */
|
||||
sched_update_tick_dependency(rq);
|
||||
}
|
||||
@ -2016,6 +2049,16 @@ void arch_scale_freq_tick(void)
|
||||
#endif
|
||||
|
||||
#ifndef arch_scale_freq_capacity
|
||||
/**
|
||||
* arch_scale_freq_capacity - get the frequency scale factor of a given CPU.
|
||||
* @cpu: the CPU in question.
|
||||
*
|
||||
* Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e.
|
||||
*
|
||||
* f_curr
|
||||
* ------ * SCHED_CAPACITY_SCALE
|
||||
* f_max
|
||||
*/
|
||||
static __always_inline
|
||||
unsigned long arch_scale_freq_capacity(int cpu)
|
||||
{
|
||||
@ -2349,12 +2392,35 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
|
||||
#ifdef CONFIG_UCLAMP_TASK
|
||||
unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
|
||||
|
||||
/**
|
||||
* uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
|
||||
* @rq: The rq to clamp against. Must not be NULL.
|
||||
* @util: The util value to clamp.
|
||||
* @p: The task to clamp against. Can be NULL if you want to clamp
|
||||
* against @rq only.
|
||||
*
|
||||
* Clamps the passed @util to the max(@rq, @p) effective uclamp values.
|
||||
*
|
||||
* If sched_uclamp_used static key is disabled, then just return the util
|
||||
* without any clamping since uclamp aggregation at the rq level in the fast
|
||||
* path is disabled, rendering this operation a NOP.
|
||||
*
|
||||
* Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
|
||||
* will return the correct effective uclamp value of the task even if the
|
||||
* static key is disabled.
|
||||
*/
|
||||
static __always_inline
|
||||
unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
|
||||
struct task_struct *p)
|
||||
{
|
||||
unsigned long min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
|
||||
unsigned long max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
|
||||
unsigned long min_util;
|
||||
unsigned long max_util;
|
||||
|
||||
if (!static_branch_likely(&sched_uclamp_used))
|
||||
return util;
|
||||
|
||||
min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
|
||||
max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
|
||||
|
||||
if (p) {
|
||||
min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN));
|
||||
@ -2371,6 +2437,19 @@ unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
|
||||
|
||||
return clamp(util, min_util, max_util);
|
||||
}
|
||||
|
||||
/*
|
||||
* When uclamp is compiled in, the aggregation at rq level is 'turned off'
|
||||
* by default in the fast path and only gets turned on once userspace performs
|
||||
* an operation that requires it.
|
||||
*
|
||||
* Returns true if userspace opted-in to use uclamp and aggregation at rq level
|
||||
* hence is active.
|
||||
*/
|
||||
static inline bool uclamp_is_used(void)
|
||||
{
|
||||
return static_branch_likely(&sched_uclamp_used);
|
||||
}
|
||||
#else /* CONFIG_UCLAMP_TASK */
|
||||
static inline
|
||||
unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
|
||||
@ -2378,6 +2457,11 @@ unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
|
||||
{
|
||||
return util;
|
||||
}
|
||||
|
||||
static inline bool uclamp_is_used(void)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
#endif /* CONFIG_UCLAMP_TASK */
|
||||
|
||||
#ifdef arch_scale_freq_capacity
|
||||
|
||||
@ -102,12 +102,6 @@ prio_changed_stop(struct rq *rq, struct task_struct *p, int oldprio)
|
||||
BUG(); /* how!?, what priority? */
|
||||
}
|
||||
|
||||
static unsigned int
|
||||
get_rr_interval_stop(struct rq *rq, struct task_struct *task)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void update_curr_stop(struct rq *rq)
|
||||
{
|
||||
}
|
||||
@ -115,8 +109,8 @@ static void update_curr_stop(struct rq *rq)
|
||||
/*
|
||||
* Simple, special scheduling class for the per-CPU stop tasks:
|
||||
*/
|
||||
const struct sched_class stop_sched_class = {
|
||||
.next = &dl_sched_class,
|
||||
const struct sched_class stop_sched_class
|
||||
__attribute__((section("__stop_sched_class"))) = {
|
||||
|
||||
.enqueue_task = enqueue_task_stop,
|
||||
.dequeue_task = dequeue_task_stop,
|
||||
@ -136,8 +130,6 @@ const struct sched_class stop_sched_class = {
|
||||
|
||||
.task_tick = task_tick_stop,
|
||||
|
||||
.get_rr_interval = get_rr_interval_stop,
|
||||
|
||||
.prio_changed = prio_changed_stop,
|
||||
.switched_to = switched_to_stop,
|
||||
.update_curr = update_curr_stop,
|
||||
|
||||
@ -1328,7 +1328,7 @@ sd_init(struct sched_domain_topology_level *tl,
|
||||
sd_flags = (*tl->sd_flags)();
|
||||
if (WARN_ONCE(sd_flags & ~TOPOLOGY_SD_FLAGS,
|
||||
"wrong sd_flags in topology description\n"))
|
||||
sd_flags &= ~TOPOLOGY_SD_FLAGS;
|
||||
sd_flags &= TOPOLOGY_SD_FLAGS;
|
||||
|
||||
/* Apply detected topology flags */
|
||||
sd_flags |= dflags;
|
||||
|
||||
@ -634,8 +634,7 @@ static int __init nrcpus(char *str)
|
||||
{
|
||||
int nr_cpus;
|
||||
|
||||
get_option(&str, &nr_cpus);
|
||||
if (nr_cpus > 0 && nr_cpus < nr_cpu_ids)
|
||||
if (get_option(&str, &nr_cpus) && nr_cpus > 0 && nr_cpus < nr_cpu_ids)
|
||||
nr_cpu_ids = nr_cpus;
|
||||
|
||||
return 0;
|
||||
|
||||
@ -1779,6 +1779,20 @@ static struct ctl_table kern_table[] = {
|
||||
.mode = 0644,
|
||||
.proc_handler = sched_rt_handler,
|
||||
},
|
||||
{
|
||||
.procname = "sched_deadline_period_max_us",
|
||||
.data = &sysctl_sched_dl_period_max,
|
||||
.maxlen = sizeof(unsigned int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec,
|
||||
},
|
||||
{
|
||||
.procname = "sched_deadline_period_min_us",
|
||||
.data = &sysctl_sched_dl_period_min,
|
||||
.maxlen = sizeof(unsigned int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec,
|
||||
},
|
||||
{
|
||||
.procname = "sched_rr_timeslice_ms",
|
||||
.data = &sysctl_sched_rr_timeslice,
|
||||
@ -1801,6 +1815,13 @@ static struct ctl_table kern_table[] = {
|
||||
.mode = 0644,
|
||||
.proc_handler = sysctl_sched_uclamp_handler,
|
||||
},
|
||||
{
|
||||
.procname = "sched_util_clamp_min_rt_default",
|
||||
.data = &sysctl_sched_uclamp_util_min_rt_default,
|
||||
.maxlen = sizeof(unsigned int),
|
||||
.mode = 0644,
|
||||
.proc_handler = sysctl_sched_uclamp_handler,
|
||||
},
|
||||
#endif
|
||||
#ifdef CONFIG_SCHED_AUTOGROUP
|
||||
{
|
||||
|
||||
@ -2193,7 +2193,7 @@ EXPORT_SYMBOL(ktime_get_coarse_ts64);
|
||||
void do_timer(unsigned long ticks)
|
||||
{
|
||||
jiffies_64 += ticks;
|
||||
calc_global_load(ticks);
|
||||
calc_global_load();
|
||||
}
|
||||
|
||||
/**
|
||||
|
||||
@ -6,6 +6,7 @@
|
||||
#include <linux/export.h>
|
||||
#include <linux/memblock.h>
|
||||
#include <linux/numa.h>
|
||||
#include <linux/sched/isolation.h>
|
||||
|
||||
/**
|
||||
* cpumask_next - get the next cpu in a cpumask
|
||||
@ -205,22 +206,27 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask)
|
||||
*/
|
||||
unsigned int cpumask_local_spread(unsigned int i, int node)
|
||||
{
|
||||
int cpu;
|
||||
int cpu, hk_flags;
|
||||
const struct cpumask *mask;
|
||||
|
||||
hk_flags = HK_FLAG_DOMAIN | HK_FLAG_MANAGED_IRQ;
|
||||
mask = housekeeping_cpumask(hk_flags);
|
||||
/* Wrap: we always want a cpu. */
|
||||
i %= num_online_cpus();
|
||||
i %= cpumask_weight(mask);
|
||||
|
||||
if (node == NUMA_NO_NODE) {
|
||||
for_each_cpu(cpu, cpu_online_mask)
|
||||
for_each_cpu(cpu, mask) {
|
||||
if (i-- == 0)
|
||||
return cpu;
|
||||
}
|
||||
} else {
|
||||
/* NUMA first. */
|
||||
for_each_cpu_and(cpu, cpumask_of_node(node), cpu_online_mask)
|
||||
for_each_cpu_and(cpu, cpumask_of_node(node), mask) {
|
||||
if (i-- == 0)
|
||||
return cpu;
|
||||
}
|
||||
|
||||
for_each_cpu(cpu, cpu_online_mask) {
|
||||
for_each_cpu(cpu, mask) {
|
||||
/* Skip NUMA nodes, done above. */
|
||||
if (cpumask_test_cpu(cpu, cpumask_of_node(node)))
|
||||
continue;
|
||||
|
||||
@ -190,3 +190,44 @@ u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
|
||||
return __iter_div_u64_rem(dividend, divisor, remainder);
|
||||
}
|
||||
EXPORT_SYMBOL(iter_div_u64_rem);
|
||||
|
||||
#ifndef mul_u64_u64_div_u64
|
||||
u64 mul_u64_u64_div_u64(u64 a, u64 b, u64 c)
|
||||
{
|
||||
u64 res = 0, div, rem;
|
||||
int shift;
|
||||
|
||||
/* can a * b overflow ? */
|
||||
if (ilog2(a) + ilog2(b) > 62) {
|
||||
/*
|
||||
* (b * a) / c is equal to
|
||||
*
|
||||
* (b / c) * a +
|
||||
* (b % c) * a / c
|
||||
*
|
||||
* if nothing overflows. Can the 1st multiplication
|
||||
* overflow? Yes, but we do not care: this can only
|
||||
* happen if the end result can't fit in u64 anyway.
|
||||
*
|
||||
* So the code below does
|
||||
*
|
||||
* res = (b / c) * a;
|
||||
* b = b % c;
|
||||
*/
|
||||
div = div64_u64_rem(b, c, &rem);
|
||||
res = div * a;
|
||||
b = rem;
|
||||
|
||||
shift = ilog2(a) + ilog2(b) - 62;
|
||||
if (shift > 0) {
|
||||
/* drop precision */
|
||||
b >>= shift;
|
||||
c >>= shift;
|
||||
if (!c)
|
||||
return res;
|
||||
}
|
||||
}
|
||||
|
||||
return res + div64_u64(a * b, c);
|
||||
}
|
||||
#endif
|
||||
|
||||
@ -11,6 +11,7 @@
|
||||
#include <linux/if_arp.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/sched/signal.h>
|
||||
#include <linux/sched/isolation.h>
|
||||
#include <linux/nsproxy.h>
|
||||
#include <net/sock.h>
|
||||
#include <net/net_namespace.h>
|
||||
@ -741,7 +742,7 @@ static ssize_t store_rps_map(struct netdev_rx_queue *queue,
|
||||
{
|
||||
struct rps_map *old_map, *map;
|
||||
cpumask_var_t mask;
|
||||
int err, cpu, i;
|
||||
int err, cpu, i, hk_flags;
|
||||
static DEFINE_MUTEX(rps_map_mutex);
|
||||
|
||||
if (!capable(CAP_NET_ADMIN))
|
||||
@ -756,6 +757,13 @@ static ssize_t store_rps_map(struct netdev_rx_queue *queue,
|
||||
return err;
|
||||
}
|
||||
|
||||
hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
|
||||
cpumask_and(mask, mask, housekeeping_cpumask(hk_flags));
|
||||
if (cpumask_empty(mask)) {
|
||||
free_cpumask_var(mask);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
map = kzalloc(max_t(unsigned int,
|
||||
RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
|
||||
GFP_KERNEL);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user