On Wed, Oct 16, 2019 at 03:23:43PM +0100, Sudeep Holla wrote: > On Wed, Oct 16, 2019 at 12:37:58PM +0200, Rafael J. Wysocki wrote: > > Hi All, > > > > The motivation for this series is to address the problem discussed here: > > > > https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@xxxxxxxxxx/T/#md2d89e95906b8c91c15f582146173dce2e86e99f > > > > and also reported here: > > > > https://lore.kernel.org/linux-pm/20191015155735.GA29105@bogus/ > > > > Plus, generally speaking, using the policy CPU as a proxy for the policy > > with respect to PM QoS does not feel particularly straightforward to me > > and adds extra complexity. > > > > Anyway, the first patch adds frequency QoS that is based on "raw" PM QoS (kind > > of in analogy with device PM QoS) and is just about min and max frequency > > requests (no direct relationship to devices). > > > > The second patch switches over cpufreq and its users to the new frequency QoS. > > [The Fixes: tag has been tentatively added to it.] > > > > The third one removes frequency request types from device PM QoS. > > > > Unfortunately, the patches are rather big, but also they are quite > > straightforward. > > > > I didn't have the time to test this series, so giving it a go would be much > > appreciated. > > Thanks for the spinning these patches so quickly. > For the record, I thought of providing the crash that this series fixes. After applying [1] which fixes the boot issue I was seeing on TC2, I started seeing the below crash, which this series fixes. FWIW, Tested-by: Sudeep Holla <sudeep.holla@xxxxxxx> -- Unable to handle kernel paging request at virtual address 31b2c303 pgd = 772b96e1 [31b2c303] *pgd=a4050003, *pmd=00000000 Internal error: Oops: 206 [#1] SMP THUMB2 Modules linked in: CPU: 1 PID: 518 Comm: bash Not tainted 5.4.0-rc3-00062-g6e3a7fd7a87e-dirty #123 Hardware name: ARM-Versatile Express PC is at blocking_notifier_chain_unregister+0x2a/0x78 LR is at blocking_notifier_chain_unregister+0x1b/0x78 Flags: NzCv IRQs on FIQs off Mode SVC_32 ISA Thumb Segment user Control: 70c5387d Table: a57b08c0 DAC: 55555555 Process bash (pid: 518, stack limit = 0x018ebe57) (blocking_notifier_chain_unregister) from (dev_pm_qos_remove_notifier+0x5d/0xb4) (dev_pm_qos_remove_notifier) from (cpufreq_policy_free+0x77/0xc8) (cpufreq_policy_free) from (subsys_interface_unregister+0x4f/0x80) (subsys_interface_unregister) from (cpufreq_unregister_driver+0x29/0x6c) (cpufreq_unregister_driver) from (bL_cpufreq_switcher_notifier+0x41/0x4c) (bL_cpufreq_switcher_notifier) from (notifier_call_chain+0x3d/0x58) (notifier_call_chain) from (blocking_notifier_call_chain+0x29/0x38) (blocking_notifier_call_chain) from (bL_activation_notify+0x13/0x40) (bL_activation_notify) from (bL_switcher_active_store+0x59/0x190) (bL_switcher_active_store) from (kernfs_fop_write+0x85/0x12c) (kernfs_fop_write) from (__vfs_write+0x21/0x130) (__vfs_write) from (vfs_write+0x6b/0xfc) (vfs_write) from (ksys_write+0x6d/0x90) (ksys_write) from (ret_fast_syscall+0x1/0x5a)
