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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Mar 20, 2024 at 10:22:22PM +0530, Sumit Gupta wrote: > Hi Beata, > > > > On Tuesday 12 Mar 2024 at 08:34:28 (+0000), Beata Michalska wrote: > > > > Introducing arm64 specific version of arch_freq_get_on_cpu, cashing on > > > > existing implementation for FIE and AMUv1 support: the frequency scale > > > > factor, updated on each sched tick, serves as a base for retrieving > > > > the frequency for a given CPU, representing an average frequency > > > > reported between the ticks - thus its accuracy is limited. > > > > > > > > The changes have been rather lightly (due to some limitations) tested on > > > > an FVP model. > > > > > > > > Relevant discussions: > > > > [1] https://lore.kernel.org/all/20240229162520.970986-1-vanshikonda@os.amperecomputing.com/ > > > > [2] https://lore.kernel.org/all/7eozim2xnepacnnkzxlbx34hib4otycnbn4dqymfziqou5lw5u@5xzpv3t7sxo3/ > > > > [3] https://lore.kernel.org/all/20231212072617.14756-1-lihuisong@huawei.com/ > > > > [4] https://lore.kernel.org/lkml/ZIHpd6unkOtYVEqP@e120325.cambridge.arm.com/T/#m4e74cb5a0aaa353c60fedc6cfb95ab7a6e381e3c > > > > > > > > v3: > > > > - dropping changes to cpufreq_verify_current_freq > > > > - pulling in changes from Ionela initializing capacity_freq_ref to 0 > > > > (thanks for that!) and applying suggestions made by her during last review: > > > > - switching to arch_scale_freq_capacity and arch_scale_freq_ref when > > > > reversing freq scale factor computation > > > > - swapping shift with multiplication > > > > - adding time limit for considering last scale update as valid > > > > - updating frequency scale factor upon entering idle > > > > > > > > v2: > > > > - Splitting the patches > > > > - Adding comment for full dyntick mode > > > > - Plugging arch_freq_get_on_cpu into cpufreq_verify_current_freq instead > > > > of in show_cpuinfo_cur_freq to allow the framework to stay more in sync > > > > with potential freq changes > > > > > > > > Beata Michalska (2): > > > > arm64: Provide an AMU-based version of arch_freq_get_on_cpu > > > > arm64: Update AMU-based frequency scale factor on entering idle > > > > > > > > Ionela Voinescu (1): > > > > arch_topology: init capacity_freq_ref to 0 > > > > > > > > > > Should there have been a patch that adds a call to > > > arch_freq_get_on_cpu() from show_cpuinfo_cur_freq() as well? > > > > > > My understanding from this [1] thread and others referenced there is > > > that was something we wanted. > > > > > Right, so I must have missunderstood that, as the way I did read it was that > > it is acceptable to keep things as they are wrt cpufreq sysfs entries. > > > > --- > > BR > > Beata > > > [1] https://lore.kernel.org/lkml/2cfbc633-1e94-d741-2337-e1b0cf48b81b@nvidia.com/ > > > > > > Thanks, > > > Ionela. > > > > > Yes, the change to show_cpuinfo_cur_freq from [1] is needed. > Noted. Will send an update including fixes and this requested change. --- BR Beata > [1] > https://lore.kernel.org/lkml/20230606155754.245998-1-beata.michalska@arm.com/ > > Thank you, > Sumit Gupta _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel