In Brief: [PATCH v5 1/2] sched/topology: Remove EM_MAX_COMPLEXITY limit Since the EAS complexity was greatly reduced, bigger platforms can handle EAS. To reflect this improvement, remove the EAS complexity check. [PATCH v5 2/2] sched/topology: change behaviour of sysctl sched_energy_aware based on the platform Depending on the platform sysctl will either enable/disable EAS and NOP in case if EAS is not supported. Patchset contains these two patches. Second patch depends on the first patch to be applied first. v4->v5: sched_is_eas_possible missed handling of case when EM complexity was high. Dietmar suggested that there was work done already which removes these checks. Since it makes sched_is_eas_possible cleaner, picked up that patch along with v4 and made it as a patchset. Instead of using first CPU in cpu_active_mask, doing a simple loop across all CPU in cpu_active_mask to check if there is any asymmetric CPU capacities since it was breaking EAS capabilities over CPUSET islands. v3->v4: valentin suggested it would be better to consider simpler approach that was mentioned in v2. It is a standard approach to keep the knob visible but change how read and write are handled. Did that and Refactored the code to use a common function in build_perf_domains and in sysctl handler. v2->v3: Chen Yu and Pierre Gondois both pointed out that if platform becomes capable of EAS later, this patch was not allowing that to happen. Addressed that by using a variable to indicate the sysctl change and re-worded the commit message with desired behaviour, v1->v2: Chen Yu had pointed out that this will not destroy the perf domains on architectures where EAS is supported by changing the sysctl. [v1] Link: https://lore.kernel.org/lkml/20230829065040.920629-1-sshegde@xxxxxxxxxxxxxxxxxx/ [v2] Link: https://lore.kernel.org/lkml/20230901065249.137242-1-sshegde@xxxxxxxxxxxxxxxxxx/ [v3] Link: https://lore.kernel.org/lkml/20230913114807.665094-1-sshegde@xxxxxxxxxxxxxxxxxx/ [v4] Link: https://lore.kernel.org/lkml/20230926100046.405188-1-sshegde@xxxxxxxxxxxxxxxxxx/ Pierre Gondois (1): sched/topology: Remove EM_MAX_COMPLEXITY limit Shrikanth Hegde (1): change behaviour of sysctl sched_energy_aware based on the platform Documentation/admin-guide/sysctl/kernel.rst | 3 +- Documentation/scheduler/sched-energy.rst | 29 +--- kernel/sched/topology.c | 151 ++++++++++---------- 3 files changed, 82 insertions(+), 101 deletions(-) -- 2.39.3
