On 05/08/2019 09:42, Martin Kepplinger wrote: > On 05.08.19 09:39, Daniel Lezcano wrote: >> On 05/08/2019 08:53, Martin Kepplinger wrote: >> >> [ ... ] >> >>>>> +static s64 cpuidle_cooling_runtime(struct cpuidle_cooling_device >>>>> *idle_cdev) >>>>> +{ >>>>> + s64 next_wakeup; >>>>> + unsigned long state = idle_cdev->state; >>>>> + >>>>> + /* >>>>> + * The function should not be called when there is no >>>>> + * mitigation because: >>>>> + * - that does not make sense >>>>> + * - we end up with a division by zero >>>>> + */ >>>>> + if (!state) >>>>> + return 0; >>>>> + >>>>> + next_wakeup = (s64)((idle_cdev->idle_cycle * 100) / state) - >>>>> + idle_cdev->idle_cycle; >>>>> + >>>>> + return next_wakeup * NSEC_PER_USEC; >>>>> +} >>>>> + >>>> >>>> There is a bug in your calculation formula here when "state" becomes 100. >>>> You return 0 for the injection rate, which is the same as "rate" being 0, >>>> which is dangerous. You stop cooling when it's most necessary :) >>>> >>>> I'm not sure how much sense really being 100% idle makes, so I, when >>>> testing >>>> this, just say if (state == 100) { state = 99 }. Anyways, just don't >>>> return 0. >>>> >>> >>> oh and also, this breaks S3 suspend: >> >> What breaks the S3 suspend? The idle cooling device or the bug above ? > > The idle cooling device. I have to configure it out: remove > CONFIG_CPU_IDLE_THERMAL to test suspend/resume again. Errors in the > kernel log, see below.
Ok, thanks for reporting. I'll fix the issue. >>> Aug 5 06:09:20 pureos kernel: [ 807.487887] PM: suspend entry (deep) >>> Aug 5 06:09:40 pureos kernel: [ 807.501148] Filesystems sync: 0.013 >>> seconds >>> Aug 5 06:09:40 pureos kernel: [ 807.501591] Freezing user space >>> processes ... (elapsed 0.003 seconds) done. >>> Aug 5 06:09:40 pureos kernel: [ 807.504741] OOM killer disabled. >>> Aug 5 06:09:40 pureos kernel: [ 807.504744] Freezing remaining >>> freezable tasks ... >>> Aug 5 06:09:40 pureos kernel: [ 827.517712] Freezing of tasks failed >>> after 20.002 seconds (4 tasks refusing to freeze, wq_busy=0): >>> Aug 5 06:09:40 pureos kernel: [ 827.527122] thermal-idle/0 S 0 >>> 161 2 0x00000028 >>> Aug 5 06:09:40 pureos kernel: [ 827.527131] Call trace: >>> Aug 5 06:09:40 pureos kernel: [ 827.527148] __switch_to+0xb4/0x200 >>> Aug 5 06:09:40 pureos kernel: [ 827.527156] __schedule+0x1e0/0x488 >>> Aug 5 06:09:40 pureos kernel: [ 827.527162] schedule+0x38/0xc8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527169] smpboot_thread_fn+0x250/0x2a8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527176] kthread+0xf4/0x120 >>> Aug 5 06:09:40 pureos kernel: [ 827.527182] ret_from_fork+0x10/0x18 >>> Aug 5 06:09:40 pureos kernel: [ 827.527186] thermal-idle/1 S 0 >>> 162 2 0x00000028 >>> Aug 5 06:09:40 pureos kernel: [ 827.527192] Call trace: >>> Aug 5 06:09:40 pureos kernel: [ 827.527197] __switch_to+0x188/0x200 >>> Aug 5 06:09:40 pureos kernel: [ 827.527203] __schedule+0x1e0/0x488 >>> Aug 5 06:09:40 pureos kernel: [ 827.527208] schedule+0x38/0xc8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527213] smpboot_thread_fn+0x250/0x2a8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527218] kthread+0xf4/0x120 >>> Aug 5 06:09:40 pureos kernel: [ 827.527222] ret_from_fork+0x10/0x18 >>> Aug 5 06:09:40 pureos kernel: [ 827.527226] thermal-idle/2 S 0 >>> 163 2 0x00000028 >>> Aug 5 06:09:40 pureos kernel: [ 827.527231] Call trace: >>> Aug 5 06:09:40 pureos kernel: [ 827.527237] __switch_to+0xb4/0x200 >>> Aug 5 06:09:40 pureos kernel: [ 827.527242] __schedule+0x1e0/0x488 >>> Aug 5 06:09:40 pureos kernel: [ 827.527247] schedule+0x38/0xc8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527259] smpboot_thread_fn+0x250/0x2a8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527264] kthread+0xf4/0x120 >>> Aug 5 06:09:40 pureos kernel: [ 827.527268] ret_from_fork+0x10/0x18 >>> Aug 5 06:09:40 pureos kernel: [ 827.527272] thermal-idle/3 S 0 >>> 164 2 0x00000028 >>> Aug 5 06:09:40 pureos kernel: [ 827.527278] Call trace: >>> Aug 5 06:09:40 pureos kernel: [ 827.527283] __switch_to+0xb4/0x200 >>> Aug 5 06:09:40 pureos kernel: [ 827.527288] __schedule+0x1e0/0x488 >>> Aug 5 06:09:40 pureos kernel: [ 827.527293] schedule+0x38/0xc8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527298] smpboot_thread_fn+0x250/0x2a8 >>> Aug 5 06:09:40 pureos kernel: [ 827.527303] kthread+0xf4/0x120 >>> Aug 5 06:09:40 pureos kernel: [ 827.527308] ret_from_fork+0x10/0x18 >>> Aug 5 06:09:40 pureos kernel: [ 827.527375] Restarting kernel threads >>> ... done. >>> Aug 5 06:09:40 pureos kernel: [ 827.527771] OOM killer enabled. >>> Aug 5 06:09:40 pureos kernel: [ 827.527772] Restarting tasks ... done. >>> Aug 5 06:09:40 pureos kernel: [ 827.528926] PM: suspend exit >>> >>> >>> do you know where things might go wrong here? >>> >>> thanks, >>> >>> martin >>> >> >> > -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog