On Tue, 9 Jan 2024 at 12:34, Dietmar Eggemann <dietmar.eggemann@xxxxxxx> wrote: > > On 08/01/2024 14:48, Vincent Guittot wrote: > > Following the consolidation and cleanup of CPU capacity in [1], this serie > > reworks how the scheduler gets the pressures on CPUs. We need to take into > > account all pressures applied by cpufreq on the compute capacity of a CPU > > for dozens of ms or more and not only cpufreq cooling device or HW > > mitigiations. we split the pressure applied on CPU's capacity in 2 parts: > > - one from cpufreq and freq_qos > > - one from HW high freq mitigiation. > > > > The next step will be to add a dedicated interface for long standing > > capping of the CPU capacity (i.e. for seconds or more) like the > > scaling_max_freq of cpufreq sysfs. The latter is already taken into > > account by this serie but as a temporary pressure which is not always the > > best choice when we know that it will happen for seconds or more. > > I guess this is related to the 'user space system pressure' (*) slide of > your OSPM '23 talk. yes > > Where do you draw the line when it comes to time between (*) and the > 'medium pace system pressure' (e.g. thermal and FREQ_QOS). My goal is to consider the /sys/../scaling_max_freq as the 'user space system pressure' > > IIRC, with (*) you want to rebuild the sched domains etc. The easiest way would be to rebuild the sched_domain but the cost is not small so I would prefer to skip the rebuild and add a new signal that keep track on this capped capacity > > > > > [1] https://lore.kernel.org/lkml/20231211104855.558096-1-vincent.guittot@xxxxxxxxxx/ > > > > Change since v1: > > - Rework cpufreq_update_pressure() > > > > Change since v1: > > - Use struct cpufreq_policy as parameter of cpufreq_update_pressure() > > - Fix typos and comments > > - Make sched_thermal_decay_shift boot param as deprecated > > > > Vincent Guittot (5): > > cpufreq: Add a cpufreq pressure feedback for the scheduler > > sched: Take cpufreq feedback into account > > thermal/cpufreq: Remove arch_update_thermal_pressure() > > sched: Rename arch_update_thermal_pressure into > > arch_update_hw_pressure > > sched/pelt: Remove shift of thermal clock > > > > .../admin-guide/kernel-parameters.txt | 1 + > > arch/arm/include/asm/topology.h | 6 +- > > arch/arm64/include/asm/topology.h | 6 +- > > drivers/base/arch_topology.c | 26 ++++---- > > drivers/cpufreq/cpufreq.c | 36 +++++++++++ > > drivers/cpufreq/qcom-cpufreq-hw.c | 4 +- > > drivers/thermal/cpufreq_cooling.c | 3 - > > include/linux/arch_topology.h | 8 +-- > > include/linux/cpufreq.h | 10 +++ > > include/linux/sched/topology.h | 8 +-- > > .../{thermal_pressure.h => hw_pressure.h} | 14 ++--- > > include/trace/events/sched.h | 2 +- > > init/Kconfig | 12 ++-- > > kernel/sched/core.c | 8 +-- > > kernel/sched/fair.c | 63 +++++++++---------- > > kernel/sched/pelt.c | 18 +++--- > > kernel/sched/pelt.h | 16 ++--- > > kernel/sched/sched.h | 22 +------ > > 18 files changed, 144 insertions(+), 119 deletions(-) > > rename include/trace/events/{thermal_pressure.h => hw_pressure.h} (55%) >
