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2021-02-17sched/topology: Fix sched_domain_topology_level alloc in sched_init_numa()Dietmar Eggemann1-1/+1
Commit "sched/topology: Make sched_init_numa() use a set for the deduplicating sort" allocates 'i + nr_levels (level)' instead of 'i + nr_levels + 1' sched_domain_topology_level. This led to an Oops (on Arm64 juno with CONFIG_SCHED_DEBUG): sched_init_domains build_sched_domains() __free_domain_allocs() __sdt_free() { ... for_each_sd_topology(tl) ... sd = *per_cpu_ptr(sdd->sd, j); <-- ... } Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Tested-by: Barry Song <song.bao.hua@hisilicon.com> Link: https://lkml.kernel.org/r/6000e39e-7d28-c360-9cd6-8798fd22a9bf@arm.com
2021-01-27sched/topology: Make sched_init_numa() use a set for the deduplicating sortValentin Schneider1-51/+48
The deduplicating sort in sched_init_numa() assumes that the first line in the distance table contains all unique values in the entire table. I've been trying to pen what this exactly means for the topology, but it's not straightforward. For instance, topology.c uses this example: node 0 1 2 3 0: 10 20 20 30 1: 20 10 20 20 2: 20 20 10 20 3: 30 20 20 10 0 ----- 1 | / | | / | | / | 2 ----- 3 Which works out just fine. However, if we swap nodes 0 and 1: 1 ----- 0 | / | | / | | / | 2 ----- 3 we get this distance table: node 0 1 2 3 0: 10 20 20 20 1: 20 10 20 30 2: 20 20 10 20 3: 20 30 20 10 Which breaks the deduplicating sort (non-representative first line). In this case this would just be a renumbering exercise, but it so happens that we can have a deduplicating sort that goes through the whole table in O(n²) at the extra cost of a temporary memory allocation (i.e. any form of set). The ACPI spec (SLIT) mentions distances are encoded on 8 bits. Following this, implement the set as a 256-bits bitmap. Should this not be satisfactory (i.e. we want to support 32-bit values), then we'll have to go for some other sparse set implementation. This has the added benefit of letting us allocate just the right amount of memory for sched_domains_numa_distance[], rather than an arbitrary (nr_node_ids + 1). Note: DT binding equivalent (distance-map) decodes distances as 32-bit values. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210122123943.1217-2-valentin.schneider@arm.com
2020-11-19sched/topology: Condition EAS enablement on FIE supportIonela Voinescu1-0/+9
In order to make accurate predictions across CPUs and for all performance states, Energy Aware Scheduling (EAS) needs frequency-invariant load tracking signals. EAS task placement aims to minimize energy consumption, and does so in part by limiting the search space to only CPUs with the highest spare capacity (CPU capacity - CPU utilization) in their performance domain. Those candidates are the placement choices that will keep frequency at its lowest possible and therefore save the most energy. But without frequency invariance, a CPU's utilization is relative to the CPU's current performance level, and not relative to its maximum performance level, which determines its capacity. As a result, it will fail to correctly indicate any potential spare capacity obtained by an increase in a CPU's performance level. Therefore, a non-invariant utilization signal would render the EAS task placement logic invalid. Now that we properly report support for the Frequency Invariance Engine (FIE) through arch_scale_freq_invariant() for arm and arm64 systems, while also ensuring a re-evaluation of the EAS use conditions for possible invariance status change, we can assert this is the case when initializing EAS. Warn and bail out otherwise. Suggested-by: Quentin Perret <qperret@google.com> Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20201027180713.7642-4-ionela.voinescu@arm.com
2020-11-19sched/topology,schedutil: Wrap sched domains rebuildIonela Voinescu1-7/+11
Add the rebuild_sched_domains_energy() function to wrap the functionality that rebuilds the scheduling domains if any of the Energy Aware Scheduling (EAS) initialisation conditions change. This functionality is used when schedutil is added or removed or when EAS is enabled or disabled through the sched_energy_aware sysctl. Therefore, create a single function that is used in both these cases and that can be later reused. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Quentin Perret <qperret@google.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lkml.kernel.org/r/20201027180713.7642-2-ionela.voinescu@arm.com
2020-11-19sched/topology: Warn when NUMA diameter > 2Valentin Schneider1-0/+33
NUMA topologies where the shortest path between some two nodes requires three or more hops (i.e. diameter > 2) end up being misrepresented in the scheduler topology structures. This is currently detected when booting a kernel with CONFIG_SCHED_DEBUG=y + sched_debug on the cmdline, although this will only yield a warning about sched_group spans not matching sched_domain spans: ERROR: groups don't span domain->span Add an explicit warning for that case, triggered regardless of CONFIG_SCHED_DEBUG, and decorate it with an appropriate comment. The topology described in the comment can be booted up on QEMU by appending the following to your usual QEMU incantation: -smp cores=4 \ -numa node,cpus=0,nodeid=0 -numa node,cpus=1,nodeid=1, \ -numa node,cpus=2,nodeid=2, -numa node,cpus=3,nodeid=3, \ -numa dist,src=0,dst=1,val=20, -numa dist,src=0,dst=2,val=30, \ -numa dist,src=0,dst=3,val=40, -numa dist,src=1,dst=2,val=20, \ -numa dist,src=1,dst=3,val=30, -numa dist,src=2,dst=3,val=20 A somewhat more realistic topology (6-node mesh) with the same affliction can be conjured with: -smp cores=6 \ -numa node,cpus=0,nodeid=0 -numa node,cpus=1,nodeid=1, \ -numa node,cpus=2,nodeid=2, -numa node,cpus=3,nodeid=3, \ -numa node,cpus=4,nodeid=4, -numa node,cpus=5,nodeid=5, \ -numa dist,src=0,dst=1,val=20, -numa dist,src=0,dst=2,val=30, \ -numa dist,src=0,dst=3,val=40, -numa dist,src=0,dst=4,val=30, \ -numa dist,src=0,dst=5,val=20, \ -numa dist,src=1,dst=2,val=20, -numa dist,src=1,dst=3,val=30, \ -numa dist,src=1,dst=4,val=20, -numa dist,src=1,dst=5,val=30, \ -numa dist,src=2,dst=3,val=20, -numa dist,src=2,dst=4,val=30, \ -numa dist,src=2,dst=5,val=40, \ -numa dist,src=3,dst=4,val=20, -numa dist,src=3,dst=5,val=30, \ -numa dist,src=4,dst=5,val=20 Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@techsingularity.net> Link: https://lore.kernel.org/lkml/jhjtux5edo2.mognet@arm.com
2020-10-29sched/deadline: Optimize sched_dl_global_validate()Peng Liu1-0/+1
Under CONFIG_SMP, dl_bw is per root domain, but not per CPU. When checking or updating dl_bw, currently iterating every CPU is overdoing, just need iterate each root domain once. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Peng Liu <iwtbavbm@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Acked-by: Juri Lelli <juri.lelli@redhat.com> Link: https://lkml.kernel.org/r/78d21ee792cc48ff79e8cd62a5f26208463684d6.1602171061.git.iwtbavbm@gmail.com
2020-10-12Merge tag 'sched-core-2020-10-12' of ↵Linus Torvalds1-29/+40
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - reorganize & clean up the SD* flags definitions and add a bunch of sanity checks. These new checks caught quite a few bugs or at least inconsistencies, resulting in another set of patches. - rseq updates, add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ - add a new tracepoint to improve CPU capacity tracking - improve overloaded SMP system load-balancing behavior - tweak SMT balancing - energy-aware scheduling updates - NUMA balancing improvements - deadline scheduler fixes and improvements - CPU isolation fixes - misc cleanups, simplifications and smaller optimizations * tag 'sched-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) sched/deadline: Unthrottle PI boosted threads while enqueuing sched/debug: Add new tracepoint to track cpu_capacity sched/fair: Tweak pick_next_entity() rseq/selftests: Test MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ rseq/selftests,x86_64: Add rseq_offset_deref_addv() rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ sched/fair: Use dst group while checking imbalance for NUMA balancer sched/fair: Reduce busy load balance interval sched/fair: Minimize concurrent LBs between domain level sched/fair: Reduce minimal imbalance threshold sched/fair: Relax constraint on task's load during load balance sched/fair: Remove the force parameter of update_tg_load_avg() sched/fair: Fix wrong cpu selecting from isolated domain sched: Remove unused inline function uclamp_bucket_base_value() sched/rt: Disable RT_RUNTIME_SHARE by default sched/deadline: Fix stale throttling on de-/boosted tasks sched/numa: Use runnable_avg to classify node sched/topology: Move sd_flag_debug out of #ifdef CONFIG_SYSCTL MAINTAINERS: Add myself as SCHED_DEADLINE reviewer sched/topology: Move SD_DEGENERATE_GROUPS_MASK out of linux/sched/topology.h ...
2020-09-25sched/fair: Reduce busy load balance intervalVincent Guittot1-1/+1
The busy_factor, which increases load balance interval when a cpu is busy, is set to 32 by default. This value generates some huge LB interval on large system like the THX2 made of 2 node x 28 cores x 4 threads. For such system, the interval increases from 112ms to 3584ms at MC level. And from 228ms to 7168ms at NUMA level. Even on smaller system, a lower busy factor has shown improvement on the fair distribution of the running time so let reduce it for all. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Phil Auld <pauld@redhat.com> Link: https://lkml.kernel.org/r/20200921072424.14813-5-vincent.guittot@linaro.org
2020-09-25sched/fair: Reduce minimal imbalance thresholdVincent Guittot1-1/+1
The 25% default imbalance threshold for DIE and NUMA domain is large enough to generate significant unfairness between threads. A typical example is the case of 11 threads running on 2x4 CPUs. The imbalance of 20% between the 2 groups of 4 cores is just low enough to not trigger the load balance between the 2 groups. We will have always the same 6 threads on one group of 4 CPUs and the other 5 threads on the other group of CPUS. With a fair time sharing in each group, we ends up with +20% running time for the group of 5 threads. Consider decreasing the imbalance threshold for overloaded case where we use the load to balance task and to ensure fair time sharing. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Phil Auld <pauld@redhat.com> Acked-by: Hillf Danton <hdanton@sina.com> Link: https://lkml.kernel.org/r/20200921072424.14813-3-vincent.guittot@linaro.org
2020-09-09sched/topology: Move sd_flag_debug out of #ifdef CONFIG_SYSCTLValentin Schneider1-0/+6
The last sd_flag_debug shuffle inadvertently moved its definition within an #ifdef CONFIG_SYSCTL region. While CONFIG_SYSCTL is indeed required to produce the sched domain ctl interface (which uses sd_flag_debug to output flag names), it isn't required to run any assertion on the sched_domain hierarchy itself. Move the definition of sd_flag_debug to a CONFIG_SCHED_DEBUG region of topology.c. Now at long last we have: - sd_flag_debug declared in include/linux/sched/topology.h iff CONFIG_SCHED_DEBUG=y - sd_flag_debug defined in kernel/sched/topology.c, conditioned by: - CONFIG_SCHED_DEBUG, with an explicit #ifdef block - CONFIG_SMP, as a requirement to compile topology.c With this change, all symbols pertaining to SD flag metadata (with the exception of __SD_FLAG_CNT) are now defined exclusively within topology.c Fixes: 8fca9494d4b4 ("sched/topology: Move sd_flag_debug out of linux/sched/topology.h") Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200908184956.23369-1-valentin.schneider@arm.com
2020-08-26sched/topology: Move SD_DEGENERATE_GROUPS_MASK out of linux/sched/topology.hValentin Schneider1-0/+7
SD_DEGENERATE_GROUPS_MASK is only useful for sched/topology.c, but still gets defined for anyone who imports topology.h, leading to a flurry of unused variable warnings. Move it out of the header and place it next to the SD degeneration functions in sched/topology.c. Fixes: 4ee4ea443a5d ("sched/topology: Introduce SD metaflag for flags needing > 1 groups") Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200825133216.9163-2-valentin.schneider@arm.com
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-3/+3
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-19sched/topology: Mark SD_PREFER_SIBLING as SDF_NEEDS_GROUPSValentin Schneider1-1/+1
SD_PREFER_SIBLING is currently considered in sd_parent_degenerate() but not in sd_degenerate(). It too hinges on load balancing, and thus won't have any effect when set on a domain with a single group. Add it to SD_DEGENERATE_GROUPS_MASK. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-12-valentin.schneider@arm.com
2020-08-19sched/topology: Propagate SD_ASYM_CPUCAPACITY upwardsValentin Schneider1-2/+1
We currently set this flag *only* on domains whose topology level exactly match the level where we detect asymmetry (as returned by asym_cpu_capacity_level()). This is rather problematic. Say there are two clusters in the system, one with a lone big CPU and the other with a mix of big and LITTLE CPUs (as is allowed by DynamIQ): DIE [ ] MC [ ][ ] 0 1 2 3 4 L L B B B asym_cpu_capacity_level() will figure out that the MC level is the one where all CPUs can see a CPU of max capacity, and we will thus set SD_ASYM_CPUCAPACITY at MC level for all CPUs. That lone big CPU will degenerate its MC domain, since it would be alone in there, and will end up with just a DIE domain. Since the flag was only set at MC, this CPU ends up not seeing any SD with the flag set, which is broken. Rather than clearing dflags at every topology level, clear it before entering the topology level loop. This will properly propagate upwards flags that are set starting from a certain level. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Quentin Perret <qperret@google.com> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-11-valentin.schneider@arm.com
2020-08-19sched/topology: Remove SD_SERIALIZE degeneration special caseValentin Schneider1-4/+2
If there is only a single NUMA node in the system, the only NUMA topology level that will be generated will be NODE (identity distance), which doesn't have SD_SERIALIZE. This means we don't need this special case in sd_parent_degenerate(), as having the NODE level "naturally" covers it. Thus, remove it. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-10-valentin.schneider@arm.com
2020-08-19sched/topology: Use prebuilt SD flag degeneration maskValentin Schneider1-16/+4
Leverage SD_DEGENERATE_GROUPS_MASK in sd_degenerate() and sd_parent_degenerate(). Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-9-valentin.schneider@arm.com
2020-08-19sched/topology: Verify SD_* flags setup when sched_debug is onValentin Schneider1-0/+17
Now that we have some description of what we expect the flags layout to be, we can use that to assert at runtime that the actual layout is sane. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-6-valentin.schneider@arm.com
2020-08-19ARM, sched/topology: Remove SD_SHARE_POWERDOMAINValentin Schneider1-7/+3
This flag was introduced in 2014 by commit: d77b3ed5c9f8 ("sched: Add a new SD_SHARE_POWERDOMAIN for sched_domain") but AFAIA it was never leveraged by the scheduler. The closest thing I can think of is EAS caring about frequency domains, and it does that by leveraging performance domains. Remove the flag. No change in functionality is expected. Suggested-by: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-2-valentin.schneider@arm.com
2020-08-04Merge tag 'pm-5.9-rc1' of ↵Linus Torvalds1-10/+10
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "The most significant change here is the extension of the Energy Model to cover non-CPU devices (as well as CPUs) from Lukasz Luba. There is also some new hardware support (Ice Lake server idle states table for intel_idle, Sapphire Rapids and Power Limit 4 support in the RAPL driver), some new functionality in the existing drivers (eg. a new switch to disable/enable CPU energy-efficiency optimizations in intel_pstate, delayed timers in devfreq), some assorted fixes (cpufreq core, intel_pstate, intel_idle) and cleanups (eg. cpuidle-psci, devfreq), including the elimination of W=1 build warnings from cpufreq done by Lee Jones. Specifics: - Make the Energy Model cover non-CPU devices (Lukasz Luba). - Add Ice Lake server idle states table to the intel_idle driver and eliminate a redundant static variable from it (Chen Yu, Rafael Wysocki). - Eliminate all W=1 build warnings from cpufreq (Lee Jones). - Add support for Sapphire Rapids and for Power Limit 4 to the Intel RAPL power capping driver (Sumeet Pawnikar, Zhang Rui). - Fix function name in kerneldoc comments in the idle_inject power capping driver (Yangtao Li). - Fix locking issues with cpufreq governors and drop a redundant "weak" function definition from cpufreq (Viresh Kumar). - Rearrange cpufreq to register non-modular governors at the core_initcall level and allow the default cpufreq governor to be specified in the kernel command line (Quentin Perret). - Extend, fix and clean up the intel_pstate driver (Srinivas Pandruvada, Rafael Wysocki): * Add a new sysfs attribute for disabling/enabling CPU energy-efficiency optimizations in the processor. * Make the driver avoid enabling HWP if EPP is not supported. * Allow the driver to handle numeric EPP values in the sysfs interface and fix the setting of EPP via sysfs in the active mode. * Eliminate a static checker warning and clean up a kerneldoc comment. - Clean up some variable declarations in the powernv cpufreq driver (Wei Yongjun). - Fix up the ->enter_s2idle callback definition to cover the case when it points to the same function as ->idle correctly (Neal Liu). - Rearrange and clean up the PSCI cpuidle driver (Ulf Hansson). - Make the PM core emit "changed" uevent when adding/removing the "wakeup" sysfs attribute of devices (Abhishek Pandit-Subedi). - Add a helper macro for declaring PM callbacks and use it in the MMC jz4740 driver (Paul Cercueil). - Fix white space in some places in the hibernate code and make the system-wide PM code use "const char *" where appropriate (Xiang Chen, Alexey Dobriyan). - Add one more "unsafe" helper macro to the freezer to cover the NFS use case (He Zhe). - Change the language in the generic PM domains framework to use parent/child terminology and clean up a typo and some comment fromatting in that code (Kees Cook, Geert Uytterhoeven). - Update the operating performance points OPP framework (Lukasz Luba, Andrew-sh.Cheng, Valdis Kletnieks): * Refactor dev_pm_opp_of_register_em() and update related drivers. * Add a missing function export. * Allow disabled OPPs in dev_pm_opp_get_freq(). - Update devfreq core and drivers (Chanwoo Choi, Lukasz Luba, Enric Balletbo i Serra, Dmitry Osipenko, Kieran Bingham, Marc Zyngier): * Add support for delayed timers to the devfreq core and make the Samsung exynos5422-dmc driver use it. * Unify sysfs interface to use "df-" as a prefix in instance names consistently. * Fix devfreq_summary debugfs node indentation. * Add the rockchip,pmu phandle to the rk3399_dmc driver DT bindings. * List Dmitry Osipenko as the Tegra devfreq driver maintainer. * Fix typos in the core devfreq code. - Update the pm-graph utility to version 5.7 including a number of fixes related to suspend-to-idle (Todd Brandt). - Fix coccicheck errors and warnings in the cpupower utility (Shuah Khan). - Replace HTTP links with HTTPs ones in multiple places (Alexander A. Klimov)" * tag 'pm-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (71 commits) cpuidle: ACPI: fix 'return' with no value build warning cpufreq: intel_pstate: Fix EPP setting via sysfs in active mode cpufreq: intel_pstate: Rearrange the storing of new EPP values intel_idle: Customize IceLake server support PM / devfreq: Fix the wrong end with semicolon PM / devfreq: Fix indentaion of devfreq_summary debugfs node PM / devfreq: Clean up the devfreq instance name in sysfs attr memory: samsung: exynos5422-dmc: Add module param to control IRQ mode memory: samsung: exynos5422-dmc: Adjust polling interval and uptreshold memory: samsung: exynos5422-dmc: Use delayed timer as default PM / devfreq: Add support delayed timer for polling mode dt-bindings: devfreq: rk3399_dmc: Add rockchip,pmu phandle PM / devfreq: tegra: Add Dmitry as a maintainer PM / devfreq: event: Fix trivial spelling PM / devfreq: rk3399_dmc: Fix kernel oops when rockchip,pmu is absent cpuidle: change enter_s2idle() prototype cpuidle: psci: Prevent domain idlestates until consumers are ready cpuidle: psci: Convert PM domain to platform driver cpuidle: psci: Fix error path via converting to a platform driver cpuidle: psci: Fail cpuidle registration if set OSI mode failed ...
2020-06-24PM / EM: change naming convention from 'capacity' to 'performance'Lukasz Luba1-10/+10
The Energy Model uses concept of performance domain and capacity states in order to calculate power used by CPUs. Change naming convention from capacity to performance state would enable wider usage in future, e.g. upcoming support for other devices other than CPUs. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-06-15sched: correct SD_flags returned by tl->sd_flags()Peng Liu1-1/+1
During sched domain init, we check whether non-topological SD_flags are returned by tl->sd_flags(), if found, fire a waning and correct the violation, but the code failed to correct the violation. Correct this. Fixes: 143e1e28cb40 ("sched: Rework sched_domain topology definition") Signed-off-by: Peng Liu <iwtbavbm@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20200609150936.GA13060@iZj6chx1xj0e0buvshuecpZ
2020-06-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-1/+1
Pull networking updates from David Miller: 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz Augusto von Dentz. 2) Add GSO partial support to igc, from Sasha Neftin. 3) Several cleanups and improvements to r8169 from Heiner Kallweit. 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a device self-test. From Andrew Lunn. 5) Start moving away from custom driver versions, use the globally defined kernel version instead, from Leon Romanovsky. 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin. 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet. 8) Add sriov and vf support to hinic, from Luo bin. 9) Support Media Redundancy Protocol (MRP) in the bridging code, from Horatiu Vultur. 10) Support netmap in the nft_nat code, from Pablo Neira Ayuso. 11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina Dubroca. Also add ipv6 support for espintcp. 12) Lots of ReST conversions of the networking documentation, from Mauro Carvalho Chehab. 13) Support configuration of ethtool rxnfc flows in bcmgenet driver, from Doug Berger. 14) Allow to dump cgroup id and filter by it in inet_diag code, from Dmitry Yakunin. 15) Add infrastructure to export netlink attribute policies to userspace, from Johannes Berg. 16) Several optimizations to sch_fq scheduler, from Eric Dumazet. 17) Fallback to the default qdisc if qdisc init fails because otherwise a packet scheduler init failure will make a device inoperative. From Jesper Dangaard Brouer. 18) Several RISCV bpf jit optimizations, from Luke Nelson. 19) Correct the return type of the ->ndo_start_xmit() method in several drivers, it's netdev_tx_t but many drivers were using 'int'. From Yunjian Wang. 20) Add an ethtool interface for PHY master/slave config, from Oleksij Rempel. 21) Add BPF iterators, from Yonghang Song. 22) Add cable test infrastructure, including ethool interfaces, from Andrew Lunn. Marvell PHY driver is the first to support this facility. 23) Remove zero-length arrays all over, from Gustavo A. R. Silva. 24) Calculate and maintain an explicit frame size in XDP, from Jesper Dangaard Brouer. 25) Add CAP_BPF, from Alexei Starovoitov. 26) Support terse dumps in the packet scheduler, from Vlad Buslov. 27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei. 28) Add devm_register_netdev(), from Bartosz Golaszewski. 29) Minimize qdisc resets, from Cong Wang. 30) Get rid of kernel_getsockopt and kernel_setsockopt in order to eliminate set_fs/get_fs calls. From Christoph Hellwig. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits) selftests: net: ip_defrag: ignore EPERM net_failover: fixed rollback in net_failover_open() Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv" Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv" vmxnet3: allow rx flow hash ops only when rss is enabled hinic: add set_channels ethtool_ops support selftests/bpf: Add a default $(CXX) value tools/bpf: Don't use $(COMPILE.c) bpf, selftests: Use bpf_probe_read_kernel s390/bpf: Use bcr 0,%0 as tail call nop filler s390/bpf: Maintain 8-byte stack alignment selftests/bpf: Fix verifier test selftests/bpf: Fix sample_cnt shared between two threads bpf, selftests: Adapt cls_redirect to call csum_level helper bpf: Add csum_level helper for fixing up csum levels bpf: Fix up bpf_skb_adjust_room helper's skb csum setting sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf() crypto/chtls: IPv6 support for inline TLS Crypto/chcr: Fixes a coccinile check error Crypto/chcr: Fixes compilations warnings ...
2020-04-30sched/topology: Kill SD_LOAD_BALANCEValentin Schneider1-2/+1
That flag is set unconditionally in sd_init(), and no one checks for it anymore. Remove it. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200415210512.805-5-valentin.schneider@arm.com
2020-04-30sched: Remove checks against SD_LOAD_BALANCEValentin Schneider1-19/+9
The SD_LOAD_BALANCE flag is set unconditionally for all domains in sd_init(). By making the sched_domain->flags syctl interface read-only, we have removed the last piece of code that could clear that flag - as such, it will now be always present. Rather than to keep carrying it along, we can work towards getting rid of it entirely. cpusets don't need it because they can make CPUs be attached to the NULL domain (e.g. cpuset with sched_load_balance=0), or to a partitioned root_domain, i.e. a sched_domain hierarchy that doesn't span the entire system (e.g. root cpuset with sched_load_balance=0 and sibling cpusets with sched_load_balance=1). isolcpus apply the same "trick": isolated CPUs are explicitly taken out of the sched_domain rebuild (using housekeeping_cpumask()), so they get the NULL domain treatment as well. Remove the checks against SD_LOAD_BALANCE. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200415210512.805-4-valentin.schneider@arm.com
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig1-1/+1
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-06sched/topology: Don't enable EAS on SMT systemsValentin Schneider1-2/+10
EAS already requires asymmetric CPU capacities to be enabled, and mixing this with SMT is an aberration, but better be safe than sorry. Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20200227191433.31994-2-valentin.schneider@arm.com
2020-02-20sched/topology: Remove SD_BALANCE_WAKE on asymmetric capacity systemsMorten Rasmussen1-12/+3
SD_BALANCE_WAKE was previously added to lower sched_domain levels on asymmetric CPU capacity systems by commit: 9ee1cda5ee25 ("sched/core: Enable SD_BALANCE_WAKE for asymmetric capacity systems") to enable the use of find_idlest_cpu() and friends to find an appropriate CPU for tasks. That responsibility has now been shifted to select_idle_sibling() and friends, and hence the flag can be removed. Note that this causes asymmetric CPU capacity systems to no longer enter the slow wakeup path (find_idlest_cpu()) on wakeups - only on execs and forks (which is aligned with all other mainline topologies). Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com> [Changelog tweaks] Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Quentin Perret <qperret@google.com> Link: https://lkml.kernel.org/r/20200206191957.12325-3-valentin.schneider@arm.com
2020-01-17sched/topology: Assert non-NUMA topology masks don't (partially) overlapValentin Schneider1-0/+39
topology.c::get_group() relies on the assumption that non-NUMA domains do not partially overlap. Zeng Tao pointed out in [1] that such topology descriptions, while completely bogus, can end up being exposed to the scheduler. In his example (8 CPUs, 2-node system), we end up with: MC span for CPU3 == 3-7 MC span for CPU4 == 4-7 The first pass through get_group(3, sdd@MC) will result in the following sched_group list: 3 -> 4 -> 5 -> 6 -> 7 ^ / `----------------' And a later pass through get_group(4, sdd@MC) will "corrupt" that to: 3 -> 4 -> 5 -> 6 -> 7 ^ / `-----------' which will completely break things like 'while (sg != sd->groups)' when using CPU3's base sched_domain. There already are some architecture-specific checks in place such as x86/kernel/smpboot.c::topology.sane(), but this is something we can detect in the core scheduler, so it seems worthwhile to do so. Warn and abort the construction of the sched domains if such a broken topology description is detected. Note that this is somewhat expensive (O(t.c²), 't' non-NUMA topology levels and 'c' CPUs) and could be gated under SCHED_DEBUG if deemed necessary. Testing ======= Dietmar managed to reproduce this using the following qemu incantation: $ qemu-system-aarch64 -kernel ./Image -hda ./qemu-image-aarch64.img \ -append 'root=/dev/vda console=ttyAMA0 loglevel=8 sched_debug' -smp \ cores=8 --nographic -m 512 -cpu cortex-a53 -machine virt -numa \ node,cpus=0-2,nodeid=0 -numa node,cpus=3-7,nodeid=1 alongside the following drivers/base/arch_topology.c hack (AIUI wouldn't be needed if '-smp cores=X, sockets=Y' would work with qemu): 8<--- @@ -465,6 +465,9 @@ void update_siblings_masks(unsigned int cpuid) if (cpuid_topo->package_id != cpu_topo->package_id) continue; + if ((cpu < 4 && cpuid > 3) || (cpu > 3 && cpuid < 4)) + continue; + cpumask_set_cpu(cpuid, &cpu_topo->core_sibling); cpumask_set_cpu(cpu, &cpuid_topo->core_sibling); 8<--- [1]: https://lkml.kernel.org/r/1577088979-8545-1-git-send-email-prime.zeng@hisilicon.com Reported-by: Zeng Tao <prime.zeng@hisilicon.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200115160915.22575-1-valentin.schneider@arm.com
2019-11-11Merge tag 'v5.4-rc7' into sched/core, to pick up fixesIngo Molnar1-2/+9
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-29sched/topology: Allow sched_asym_cpucapacity to be disabledValentin Schneider1-1/+5
While the static key is correctly initialized as being disabled, it will remain forever enabled once turned on. This means that if we start with an asymmetric system and hotplug out enough CPUs to end up with an SMP system, the static key will remain set - which is obviously wrong. We should detect this and turn off things like misfit migration and capacity aware wakeups. As Quentin pointed out, having separate root domains makes this slightly trickier. We could have exclusive cpusets that create an SMP island - IOW, the domains within this root domain will not see any asymmetry. This means we can't just disable the key on domain destruction, we need to count how many asymmetric root domains we have. Consider the following example using Juno r0 which is 2+4 big.LITTLE, where two identical cpusets are created: they both span both big and LITTLE CPUs: asym0 asym1 [ ][ ] L L B L L B $ cgcreate -g cpuset:asym0 $ cgset -r cpuset.cpus=0,1,3 asym0 $ cgset -r cpuset.mems=0 asym0 $ cgset -r cpuset.cpu_exclusive=1 asym0 $ cgcreate -g cpuset:asym1 $ cgset -r cpuset.cpus=2,4,5 asym1 $ cgset -r cpuset.mems=0 asym1 $ cgset -r cpuset.cpu_exclusive=1 asym1 $ cgset -r cpuset.sched_load_balance=0 . (the CPU numbering may look odd because on the Juno LITTLEs are CPUs 0,3-5 and bigs are CPUs 1-2) If we make one of those SMP (IOW remove asymmetry) by e.g. hotplugging its big core, we would end up with an SMP cpuset and an asymmetric cpuset - the static key must remain set, because we still have one asymmetric root domain. With the above example, this could be done with: $ echo 0 > /sys/devices/system/cpu/cpu2/online Which would result in: asym0 asym1 [ ][ ] L L B L L When both SMP and asymmetric cpusets are present, all CPUs will observe sched_asym_cpucapacity being set (it is system-wide), but not all CPUs observe asymmetry in their sched domain hierarchy: per_cpu(sd_asym_cpucapacity, <any CPU in asym0>) == <some SD at DIE level> per_cpu(sd_asym_cpucapacity, <any CPU in asym1>) == NULL Change the simple key enablement to an increment, and decrement the key counter when destroying domains that cover asymmetric CPUs. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Dietmar.Eggemann@arm.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: hannes@cmpxchg.org Cc: lizefan@huawei.com Cc: morten.rasmussen@arm.com Cc: qperret@google.com Cc: tj@kernel.org Cc: vincent.guittot@linaro.org Fixes: df054e8445a4 ("sched/topology: Add static_key for asymmetric CPU capacity optimizations") Link: https://lkml.kernel.org/r/20191023153745.19515-3-valentin.schneider@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-29sched/topology: Don't try to build empty sched domainsValentin Schneider1-1/+4
Turns out hotplugging CPUs that are in exclusive cpusets can lead to the cpuset code feeding empty cpumasks to the sched domain rebuild machinery. This leads to the following splat: Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 235 Comm: kworker/5:2 Not tainted 5.4.0-rc1-00005-g8d495477d62e #23 Hardware name: ARM Juno development board (r0) (DT) Workqueue: events cpuset_hotplug_workfn pstate: 60000005 (nZCv daif -PAN -UAO) pc : build_sched_domains (./include/linux/arch_topology.h:23 kernel/sched/topology.c:1898 kernel/sched/topology.c:1969) lr : build_sched_domains (kernel/sched/topology.c:1966) Call trace: build_sched_domains (./include/linux/arch_topology.h:23 kernel/sched/topology.c:1898 kernel/sched/topology.c:1969) partition_sched_domains_locked (kernel/sched/topology.c:2250) rebuild_sched_domains_locked (./include/linux/bitmap.h:370 ./include/linux/cpumask.h:538 kernel/cgroup/cpuset.c:955 kernel/cgroup/cpuset.c:978 kernel/cgroup/cpuset.c:1019) rebuild_sched_domains (kernel/cgroup/cpuset.c:1032) cpuset_hotplug_workfn (kernel/cgroup/cpuset.c:3205 (discriminator 2)) process_one_work (./arch/arm64/include/asm/jump_label.h:21 ./include/linux/jump_label.h:200 ./include/trace/events/workqueue.h:114 kernel/workqueue.c:2274) worker_thread (./include/linux/compiler.h:199 ./include/linux/list.h:268 kernel/workqueue.c:2416) kthread (kernel/kthread.c:255) ret_from_fork (arch/arm64/kernel/entry.S:1167) Code: f860dae2 912802d6 aa1603e1 12800000 (f8616853) The faulty line in question is: cap = arch_scale_cpu_capacity(cpumask_first(cpu_map)); and we're not checking the return value against nr_cpu_ids (we shouldn't have to!), which leads to the above. Prevent generate_sched_domains() from returning empty cpumasks, and add some assertion in build_sched_domains() to scream bloody murder if it happens again. The above splat was obtained on my Juno r0 with the following reproducer: $ cgcreate -g cpuset:asym $ cgset -r cpuset.cpus=0-3 asym $ cgset -r cpuset.mems=0 asym $ cgset -r cpuset.cpu_exclusive=1 asym $ cgcreate -g cpuset:smp $ cgset -r cpuset.cpus=4-5 smp $ cgset -r cpuset.mems=0 smp $ cgset -r cpuset.cpu_exclusive=1 smp $ cgset -r cpuset.sched_load_balance=0 . $ echo 0 > /sys/devices/system/cpu/cpu4/online $ echo 0 > /sys/devices/system/cpu/cpu5/online Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Dietmar.Eggemann@arm.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: hannes@cmpxchg.org Cc: lizefan@huawei.com Cc: morten.rasmussen@arm.com Cc: qperret@google.com Cc: tj@kernel.org Cc: vincent.guittot@linaro.org Fixes: 05484e098448 ("sched/topology: Add SD_ASYM_CPUCAPACITY flag detection") Link: https://lkml.kernel.org/r/20191023153745.19515-2-valentin.schneider@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-17sched/topology: Don't set SD_BALANCE_WAKE on cpuset domain relaxValentin Schneider1-6/+3
As pointed out in commit 182a85f8a119 ("sched: Disable wakeup balancing") SD_BALANCE_WAKE is a tad too aggressive, and is usually left unset. However, it turns out cpuset domain relaxation will unconditionally set it on domains below the relaxation level. This made sense back when SD_BALANCE_WAKE was set unconditionally, but it no longer is the case. We can improve things slightly by noticing that set_domain_attribute() is always called after sd_init(), so rather than setting flags we can rely on whatever sd_init() is doing and only clear certain flags when above the relaxation level. While at it, slightly clean up the function and flip the relax level check to be more human readable. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: mingo@kernel.org Cc: vincent.guittot@linaro.org Cc: juri.lelli@redhat.com Cc: seto.hidetoshi@jp.fujitsu.com Cc: qperret@google.com Cc: Dietmar.Eggemann@arm.com Cc: morten.rasmussen@arm.com Link: https://lkml.kernel.org/r/20191014164408.32596-1-valentin.schneider@arm.com
2019-09-03sched/topology: Improve load balancing on AMD EPYC systemsMatt Fleming1-1/+2
SD_BALANCE_{FORK,EXEC} and SD_WAKE_AFFINE are stripped in sd_init() for any sched domains with a NUMA distance greater than 2 hops (RECLAIM_DISTANCE). The idea being that it's expensive to balance across domains that far apart. However, as is rather unfortunately explained in: commit 32e45ff43eaf ("mm: increase RECLAIM_DISTANCE to 30") the value for RECLAIM_DISTANCE is based on node distance tables from 2011-era hardware. Current AMD EPYC machines have the following NUMA node distances: node distances: node 0 1 2 3 4 5 6 7 0: 10 16 16 16 32 32 32 32 1: 16 10 16 16 32 32 32 32 2: 16 16 10 16 32 32 32 32 3: 16 16 16 10 32 32 32 32 4: 32 32 32 32 10 16 16 16 5: 32 32 32 32 16 10 16 16 6: 32 32 32 32 16 16 10 16 7: 32 32 32 32 16 16 16 10 where 2 hops is 32. The result is that the scheduler fails to load balance properly across NUMA nodes on different sockets -- 2 hops apart. For example, pinning 16 busy threads to NUMA nodes 0 (CPUs 0-7) and 4 (CPUs 32-39) like so, $ numactl -C 0-7,32-39 ./spinner 16 causes all threads to fork and remain on node 0 until the active balancer kicks in after a few seconds and forcibly moves some threads to node 4. Override node_reclaim_distance for AMD Zen. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Suravee.Suthikulpanit@amd.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas.Lendacky@amd.com Cc: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20190808195301.13222-3-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25cpusets: Rebuild root domain deadline accounting informationMathieu Poirier1-1/+12
When the topology of root domains is modified by CPUset or CPUhotplug operations information about the current deadline bandwidth held in the root domain is lost. This patch addresses the issue by recalculating the lost deadline bandwidth information by circling through the deadline tasks held in CPUsets and adding their current load to the root domain they are associated with. Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Juri Lelli <juri.lelli@redhat.com> [ Various additional modifications. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bristot@redhat.com Cc: claudio@evidence.eu.com Cc: lizefan@huawei.com Cc: longman@redhat.com Cc: luca.abeni@santannapisa.it Cc: rostedt@goodmis.org Cc: tj@kernel.org Cc: tommaso.cucinotta@santannapisa.it Link: https://lkml.kernel.org/r/20190719140000.31694-4-juri.lelli@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25sched/topology: Add partition_sched_domains_locked()Mathieu Poirier1-4/+13
Introduce the partition_sched_domains_locked() function by taking the mutex locking code out of the original function. That way the work done by partition_sched_domains_locked() can be reused without dropping the mutex lock. No change of functionality is introduced by this patch. Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bristot@redhat.com Cc: claudio@evidence.eu.com Cc: lizefan@huawei.com Cc: longman@redhat.com Cc: luca.abeni@santannapisa.it Cc: rostedt@goodmis.org Cc: tommaso.cucinotta@santannapisa.it Link: https://lkml.kernel.org/r/20190719140000.31694-2-juri.lelli@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25sched/isolation: Prefer housekeeping CPU in local nodeWanpeng Li1-0/+20
In real product setup, there will be houseeking CPUs in each nodes, it is prefer to do housekeeping from local node, fallback to global online cpumask if failed to find houseeking CPU from local node. Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/1561711901-4755-2-git-send-email-wanpengli@tencent.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity()Vincent Guittot1-4/+4
The 'struct sched_domain *sd' parameter to arch_scale_cpu_capacity() is unused since commit: 765d0af19f5f ("sched/topology: Remove the ::smt_gain field from 'struct sched_domain'") Remove it. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: gregkh@linuxfoundation.org Cc: linux@armlinux.org.uk Cc: quentin.perret@arm.com Cc: rafael@kernel.org Link: https://lkml.kernel.org/r/1560783617-5827-1-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03sched/core: Remove sd->*_idxDietmar Eggemann1-10/+0
The sched domain per rq load index files also disappear from the /proc/sys/kernel/sched_domain/cpuX/domainY directories. Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Rik van Riel <riel@surriel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Patrick Bellasi <patrick.bellasi@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Perret <quentin.perret@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Valentin Schneider <valentin.schneider@arm.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20190527062116.11512-6-dietmar.eggemann@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-19sched/topology: Update init_sched_domains() commentJuri Lelli1-3/+2
Holding hotplug lock is not a requirement anymore for callers of sched_ init_domains after commit: 6acce3ef8452 ("sched: Remove get_online_cpus() usage") Update the relative comment preceding init_sched_domains(). Signed-off-by: Juri Lelli <juri.lelli@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: cgroups@vger.kernel.org Cc: lizefan@huawei.com Link: http://lkml.kernel.org/r/20181219133445.31982-2-juri.lelli@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-10sched/topology: Skip duplicate group rewrites in build_sched_groups()Valentin Schneider1-3/+9
While staring at build_sched_domains(), I realized that get_group() does several duplicate (thus useless) writes. If you take the Arm Juno r0 (LITTLEs = [0, 3, 4, 5], bigs = [1, 2]), the sched_group build flow would look like this: ('MC[cpu]->sg' means 'per_cpu_ptr(&tl->data->sg, cpu)' with 'tl == MC') build_sched_groups(MC[CPU0]->sd, CPU0) get_group(0) -> MC[CPU0]->sg get_group(3) -> MC[CPU3]->sg get_group(4) -> MC[CPU4]->sg get_group(5) -> MC[CPU5]->sg build_sched_groups(DIE[CPU0]->sd, CPU0) get_group(0) -> DIE[CPU0]->sg get_group(1) -> DIE[CPU1]->sg <=================+ | build_sched_groups(MC[CPU1]->sd, CPU1) | get_group(1) -> MC[CPU1]->sg | get_group(2) -> MC[CPU2]->sg | | build_sched_groups(DIE[CPU1]->sd, CPU1) ^ get_group(1) -> DIE[CPU1]->sg } We've set up these two up here! get_group(3) -> DIE[CPU0]->sg } From this point on, we will only use sched_groups that have been previously visited & initialized. The only new operation will be which group pointer we affect to sd->groups. On the Juno r0 we get 32 get_group() calls, every single one of them writing to a sched_group->cpumask. However, all of the data structures we need are set up after 8 visits (see above). Return early from get_group() if we've already visited (and thus initialized) the sched_group we're looking at. Overlapping domains are not affected as they do not use build_sched_groups(). Tested on a Juno and a 2 * (Xeon E5-2690) system. ( FWIW I initially checked the refs for both sg && sg->sgc, but figured if they weren't both 0 or > 1 then something must have gone wrong, so I threw in a WARN_ON(). ) No change in functionality intended. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-10sched/topology: Fix build_sched_groups() commentValentin Schneider1-2/+2
The comment was introduced (pre 2.6.12) by: 8a7a2318dc07 ("[PATCH] sched: consolidate sched domains") and referred to sched_group->cpu_power. This was folded into sched_group->sched_group_power in commit 9c3f75cbd144 ("sched: Break out cpu_power from the sched_group structure") The comment was then updated in: ced549fa5fc1 ("sched: Remove remaining dubious usage of "power"") but should have replaced "sg->cpu_capacity" with "sg->sched_group_capacity". Do that now. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Dietmar.Eggemann@arm.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: morten.rasmussen@arm.com Cc: qais.yousef@arm.com Link: http://lkml.kernel.org/r/20190409173546.4747-3-valentin.schneider@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03sched_domain: Annotate RCU pointers properlyJoel Fernandes (Google)1-5/+5
The scheduler uses RCU API in various places to access sched_domain pointers. These cause sparse errors as below. Many new errors show up because of an annotation check I added to rcu_assign_pointer(). Let us annotate the pointers correctly which also will help sparse catch any potential future bugs. This fixes the following sparse errors: rt.c:1681:9: error: incompatible types in comparison expression deadline.c:1904:9: error: incompatible types in comparison expression core.c:519:9: error: incompatible types in comparison expression core.c:1634:17: error: incompatible types in comparison expression fair.c:6193:14: error: incompatible types in comparison expression fair.c:9883:22: error: incompatible types in comparison expression fair.c:9897:9: error: incompatible types in comparison expression sched.h:1287:9: error: incompatible types in comparison expression topology.c:612:9: error: incompatible types in comparison expression topology.c:615:9: error: incompatible types in comparison expression sched.h:1300:9: error: incompatible types in comparison expression topology.c:618:9: error: incompatible types in comparison expression sched.h:1287:9: error: incompatible types in comparison expression topology.c:621:9: error: incompatible types in comparison expression sched.h:1300:9: error: incompatible types in comparison expression topology.c:624:9: error: incompatible types in comparison expression topology.c:671:9: error: incompatible types in comparison expression stats.c:45:17: error: incompatible types in comparison expression fair.c:5998:15: error: incompatible types in comparison expression fair.c:5989:15: error: incompatible types in comparison expression fair.c:5998:15: error: incompatible types in comparison expression fair.c:5989:15: error: incompatible types in comparison expression fair.c:6120:19: error: incompatible types in comparison expression fair.c:6506:14: error: incompatible types in comparison expression fair.c:6515:14: error: incompatible types in comparison expression fair.c:6623:9: error: incompatible types in comparison expression fair.c:5970:17: error: incompatible types in comparison expression fair.c:8642:21: error: incompatible types in comparison expression fair.c:9253:9: error: incompatible types in comparison expression fair.c:9331:9: error: incompatible types in comparison expression fair.c:9519:15: error: incompatible types in comparison expression fair.c:9533:14: error: incompatible types in comparison expression fair.c:9542:14: error: incompatible types in comparison expression fair.c:9567:14: error: incompatible types in comparison expression fair.c:9597:14: error: incompatible types in comparison expression fair.c:9421:16: error: incompatible types in comparison expression fair.c:9421:16: error: incompatible types in comparison expression Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> [ From an RCU perspective. ] Reviewed-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Cc: kernel-hardening@lists.openwall.com Cc: kernel-team@android.com Link: https://lkml.kernel.org/r/20190321003426.160260-3-joel@joelfernandes.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-03-06Merge branch 'sched-core-for-linus' of ↵Linus Torvalds1-2/+31
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - refcount conversions - Solve the rq->leaf_cfs_rq_list can of worms for real. - improve power-aware scheduling - add sysctl knob for Energy Aware Scheduling - documentation updates - misc other changes" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) kthread: Do not use TIMER_IRQSAFE kthread: Convert worker lock to raw spinlock sched/fair: Use non-atomic cpumask_{set,clear}_cpu() sched/fair: Remove unused 'sd' parameter from select_idle_smt() sched/wait: Use freezable_schedule() when possible sched/fair: Prune, fix and simplify the nohz_balancer_kick() comment block sched/fair: Explain LLC nohz kick condition sched/fair: Simplify nohz_balancer_kick() sched/topology: Fix percpu data types in struct sd_data & struct s_data sched/fair: Simplify post_init_entity_util_avg() by calling it with a task_struct pointer argument sched/fair: Fix O(nr_cgroups) in the load balancing path sched/fair: Optimize update_blocked_averages() sched/fair: Fix insertion in rq->leaf_cfs_rq_list sched/fair: Add tmp_alone_branch assertion sched/core: Use READ_ONCE()/WRITE_ONCE() in move_queued_task()/task_rq_lock() sched/debug: Initialize sd_sysctl_cpus if !CONFIG_CPUMASK_OFFSTACK sched/pelt: Skip updating util_est when utilization is higher than CPU's capacity sched/fair: Update scale invariance of PELT sched/fair: Move the rq_of() helper function sched/core: Convert task_struct.stack_refcount to refcount_t ...
2019-02-11sched/topology: Fix percpu data types in struct sd_data & struct s_dataLuc Van Oostenryck1-1/+1
The percpu members of struct sd_data and s_data are declared as: struct ... ** __percpu member; So their type is: __percpu pointer to pointer to struct ... But looking at how they're used, their type should be: pointer to __percpu pointer to struct ... and they should thus be declared as: struct ... * __percpu *member; So fix the placement of '__percpu' in the definition of these structures. This addresses a bunch of Sparse's warnings like: warning: incorrect type in initializer (different address spaces) expected void const [noderef] <asn:3> *__vpp_verify got struct sched_domain ** Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190118144936.79158-1-luc.vanoostenryck@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-27sched/core: Give DCE a fighting chancePeter Zijlstra1-1/+1
All that fancy new Energy-Aware scheduling foo is hidden behind a static_key, which is awesome if you have the stuff enabled in your config. However, when you lack all the prerequisites it doesn't make any sense to pretend we'll ever actually run this, so provide a little more clue to the compiler so it can more agressively delete the code. text data bss dec hex filename 50297 976 96 51369 c8a9 defconfig-build/kernel/sched/fair.o 49227 944 96 50267 c45b defconfig-build/kernel/sched/fair.o Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-27sched/topology: Introduce a sysctl for Energy Aware SchedulingQuentin Perret1-0/+29
In its current state, Energy Aware Scheduling (EAS) starts automatically on asymmetric platforms having an Energy Model (EM). However, there are users who want to have an EM (for thermal management for example), but don't want EAS with it. In order to let users disable EAS explicitly, introduce a new sysctl called 'sched_energy_aware'. It is enabled by default so that EAS can start automatically on platforms where it makes sense. Flipping it to 0 rebuilds the scheduling domains and disables EAS. Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adharmap@codeaurora.org Cc: chris.redpath@arm.com Cc: currojerez@riseup.net Cc: dietmar.eggemann@arm.com Cc: edubezval@gmail.com Cc: gregkh@linuxfoundation.org Cc: javi.merino@kernel.org Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Cc: pkondeti@codeaurora.org Cc: rjw@rjwysocki.net Cc: skannan@codeaurora.org Cc: smuckle@google.com Cc: srinivas.pandruvada@linux.intel.com Cc: thara.gopinath@linaro.org Cc: tkjos@google.com Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/20181203095628.11858-11-quentin.perret@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-26sched: Replace call_rcu_sched() with call_rcu()Paul E. McKenney1-2/+2
Now that call_rcu()'s callback is not invoked until after all preempt-disable regions of code have completed (in addition to explicitly marked RCU read-side critical sections), call_rcu() can be used in place of call_rcu_sched(). This commit therefore makes that change. While in the area, this commit also updates an outdated header comment for for_each_domain(). Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
2018-12-11sched/toplogy: Introduce the 'sched_energy_present' static keyQuentin Perret1-4/+24
In order to make sure Energy Aware Scheduling (EAS) will not impact systems where no Energy Model is available, introduce a static key guarding the access to EAS code. Since EAS is enabled on a per-root-domain basis, the static key is enabled when at least one root domain meets all conditions for EAS. Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adharmap@codeaurora.org Cc: chris.redpath@arm.com Cc: currojerez@riseup.net Cc: dietmar.eggemann@arm.com Cc: edubezval@gmail.com Cc: gregkh@linuxfoundation.org Cc: javi.merino@kernel.org Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Cc: pkondeti@codeaurora.org Cc: rjw@rjwysocki.net Cc: skannan@codeaurora.org Cc: smuckle@google.com Cc: srinivas.pandruvada@linux.intel.com Cc: thara.gopinath@linaro.org Cc: tkjos@google.com Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/20181203095628.11858-10-quentin.perret@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-11sched/topology: Make Energy Aware Scheduling depend on schedutilQuentin Perret1-4/+24
Energy Aware Scheduling (EAS) is designed with the assumption that frequencies of CPUs follow their utilization value. When using a CPUFreq governor other than schedutil, the chances of this assumption being true are small, if any. When schedutil is being used, EAS' predictions are at least consistent with the frequency requests. Although those requests have no guarantees to be honored by the hardware, they should at least guide DVFS in the right direction and provide some hope in regards to the EAS model being accurate. To make sure EAS is only used in a sane configuration, create a strong dependency on schedutil being used. Since having sugov compiled-in does not provide that guarantee, make CPUFreq call a scheduler function on governor changes hence letting it rebuild the scheduling domains, check the governors of the online CPUs, and enable/disable EAS accordingly. Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adharmap@codeaurora.org Cc: chris.redpath@arm.com Cc: currojerez@riseup.net Cc: dietmar.eggemann@arm.com Cc: edubezval@gmail.com Cc: gregkh@linuxfoundation.org Cc: javi.merino@kernel.org Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Cc: pkondeti@codeaurora.org Cc: skannan@codeaurora.org Cc: smuckle@google.com Cc: srinivas.pandruvada@linux.intel.com Cc: thara.gopinath@linaro.org Cc: tkjos@google.com Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/20181203095628.11858-9-quentin.perret@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-11sched/topology: Disable EAS on inappropriate platformsQuentin Perret1-1/+48
Energy Aware Scheduling (EAS) in its current form is most relevant on platforms with asymmetric CPU topologies (e.g. Arm big.LITTLE) since this is where there is a lot of potential for saving energy through scheduling. This is particularly true since the Energy Model only includes the active power costs of CPUs, hence not providing enough data to compare packing-vs-spreading strategies. As such, disable EAS on root domains where the SD_ASYM_CPUCAPACITY flag is not set. While at it, disable EAS on systems where the complexity of the Energy Model is too high since that could lead to unacceptable scheduling overhead. All in all, EAS can be used on a root domain if and only if: 1. an Energy Model is available; 2. the root domain has an asymmetric CPU capacity topology; 3. the complexity of the root domain's EM is low enough to keep scheduling overheads low. Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adharmap@codeaurora.org Cc: chris.redpath@arm.com Cc: currojerez@riseup.net Cc: dietmar.eggemann@arm.com Cc: edubezval@gmail.com Cc: gregkh@linuxfoundation.org Cc: javi.merino@kernel.org Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Cc: pkondeti@codeaurora.org Cc: rjw@rjwysocki.net Cc: skannan@codeaurora.org Cc: smuckle@google.com Cc: srinivas.pandruvada@linux.intel.com Cc: thara.gopinath@linaro.org Cc: tkjos@google.com Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/20181203095628.11858-8-quentin.perret@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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