| Message ID | 20200623142138.209513-1-qperret@google.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | cpufreq: Specify the default governor on command line | expand |
On 2020.06.23 07:22 Quentin Perret wrote: > > This series enables users of prebuilt kernels (e.g. distro kernels) to > specify their CPUfreq governor of choice using the kernel command line, > instead of having to wait for the system to fully boot to userspace to > switch using the sysfs interface. This is helpful for 2 reasons: > 1. users get to choose the governor that runs during the actual boot; > 2. it simplifies the userspace boot procedure a bit (one less thing to > worry about). > > To enable this, the first patch moves all governor init calls to > core_initcall, to make sure they are registered by the time the drivers > probe. This should be relatively low impact as registering a governor > is a simple procedure (it gets added to a llist), and all governors > already load at core_initcall anyway when they're set as the default > in Kconfig. This also allows to clean-up the governors' init/exit code, > and reduces boilerplate. > > The second patch introduces the new command line parameter, inspired by > its cpuidle counterpart. More details can be found in the respective > patch headers. > > Changes in v2: > - added Viresh's ack to patch 01 > - moved the assignment of 'default_governor' in patch 02 to the governor > registration path instead of the driver registration (Viresh) > > Thanks, > Quentin > > Quentin Perret (2): > cpufreq: Register governors at core_initcall > cpufreq: Specify default governor on command line > > .../admin-guide/kernel-parameters.txt | 5 ++++ > Documentation/admin-guide/pm/cpufreq.rst | 6 ++--- > .../platforms/cell/cpufreq_spudemand.c | 26 ++----------------- > drivers/cpufreq/cpufreq.c | 23 ++++++++++++---- > drivers/cpufreq/cpufreq_conservative.c | 22 ++++------------ > drivers/cpufreq/cpufreq_ondemand.c | 24 +++++------------ > drivers/cpufreq/cpufreq_performance.c | 14 ++-------- > drivers/cpufreq/cpufreq_powersave.c | 18 +++---------- > drivers/cpufreq/cpufreq_userspace.c | 18 +++---------- > include/linux/cpufreq.h | 14 ++++++++++ > kernel/sched/cpufreq_schedutil.c | 6 +---- > 11 files changed, 62 insertions(+), 114 deletions(-) > > -- > 2.27.0.111.gc72c7da667-goog Hi Quentin, Because I am lazy and sometimes do not want to recompile the distro source, I have a need/desire for this. Tested these two grub command lines: GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 consoleblank=300 intel_pstate=disable cpufreq.default_governor=schedutil cpuidle_sysfs_switch cpuidle.governor=teo" And #GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 consoleblank=450 intel_pstate=passive cpufreq.default_governor=schedutil cpuidle_sysfs_switch cpuidle.governor=teo" And all worked as expected. I use Ubuntu as my distro, and also had to disable a startup script that switches to "ondemand", or similar, after 1 minute. As a side note (separate subject, but is one reason I tried it): My i5-9600K based computer seems to hit a power limit during boot approximately 3 seconds after kernel selection on grub. This had no effect on that issue (even when selecting powersave governor). ... Doug
Hi Doug, On Tuesday 23 Jun 2020 at 10:54:33 (-0700), Doug Smythies wrote: > Hi Quentin, > > Because I am lazy and sometimes do not want to recompile > the distro source, I have a need/desire for this. Good to know I'm not the only one ;-) > Tested these two grub command lines: > > GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 consoleblank=300 intel_pstate=disable cpufreq.default_governor=schedutil cpuidle_sysfs_switch cpuidle.governor=teo" > > And > > #GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 consoleblank=450 intel_pstate=passive cpufreq.default_governor=schedutil cpuidle_sysfs_switch cpuidle.governor=teo" > > And all worked as expected. I use Ubuntu as my distro, and also had to disable a startup script that switches to "ondemand", or similar, after 1 minute. Good, thanks for giving it a try. > As a side note (separate subject, but is one reason I tried it): > My i5-9600K based computer seems to hit a power limit during boot approximately 3 seconds after kernel selection on grub. > This had no effect on that issue (even when selecting powersave governor). Interesting ... Could you confirm that compiling with powersave as default doesn't fix the issue either? Other question, when does the intel_pstate driver start on your device? Before or after that 3 seconds boot time? Thanks, Quentin
Hi Quentin, Thanks for your quick reply. On 2020.06.23 11:05 Quentin Perret wrote: > Hi Doug, > > On Tuesday 23 Jun 2020 at 10:54:33 (-0700), Doug Smythies wrote: > > Hi Quentin, > > > > Because I am lazy and sometimes do not want to recompile > > the distro source, I have a need/desire for this. > > Good to know I'm not the only one ;-) > > > Tested these two grub command lines: > > > > GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 consoleblank=300 intel_pstate=disable > cpufreq.default_governor=schedutil cpuidle_sysfs_switch cpuidle.governor=teo" > > > > And > > > > #GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 consoleblank=450 intel_pstate=passive > cpufreq.default_governor=schedutil cpuidle_sysfs_switch cpuidle.governor=teo" > > > > And all worked as expected. I use Ubuntu as my distro, and also had to disable a startup script that > switches to "ondemand", or similar, after 1 minute. > > Good, thanks for giving it a try. > > > As a side note (separate subject, but is one reason I tried it): > > My i5-9600K based computer seems to hit a power limit during boot approximately 3 seconds after > kernel selection on grub. > > This had no effect on that issue (even when selecting powersave governor). > > Interesting ... Could you confirm that compiling with powersave as > default doesn't fix the issue either? No, it doesn't (good idea for a test though). However, the big mains spike is also gone. So, I no longer know why those power limit log bits are always set after boot. > > Other question, when does the intel_pstate driver start on your device? > Before or after that 3 seconds boot time? Before, if I understand correctly (from dmesg): [ 0.468969] intel_pstate: Intel P-state driver initializing I'll attach a couple of annotated mains power graphs. (which will likely get stripped from the on-list version of this e-mail). Currently, I am drowning in stuff that doesn't work, and will put this aside for now. I'll revive this as a new thread or a bugzilla eventually. I also tried booting with turbo disabled, no difference. Thanks for this patch set. ... Doug
This series enables users of prebuilt kernels (e.g. distro kernels) to specify their CPUfreq governor of choice using the kernel command line, instead of having to wait for the system to fully boot to userspace to switch using the sysfs interface. This is helpful for 2 reasons: 1. users get to choose the governor that runs during the actual boot; 2. it simplifies the userspace boot procedure a bit (one less thing to worry about). To enable this, the first patch moves all governor init calls to core_initcall, to make sure they are registered by the time the drivers probe. This should be relatively low impact as registering a governor is a simple procedure (it gets added to a llist), and all governors already load at core_initcall anyway when they're set as the default in Kconfig. This also allows to clean-up the governors' init/exit code, and reduces boilerplate. The second patch introduces the new command line parameter, inspired by its cpuidle counterpart. More details can be found in the respective patch headers. Changes in v2: - added Viresh's ack to patch 01 - moved the assignment of 'default_governor' in patch 02 to the governor registration path instead of the driver registration (Viresh) Thanks, Quentin Quentin Perret (2): cpufreq: Register governors at core_initcall cpufreq: Specify default governor on command line .../admin-guide/kernel-parameters.txt | 5 ++++ Documentation/admin-guide/pm/cpufreq.rst | 6 ++--- .../platforms/cell/cpufreq_spudemand.c | 26 ++----------------- drivers/cpufreq/cpufreq.c | 23 ++++++++++++---- drivers/cpufreq/cpufreq_conservative.c | 22 ++++------------ drivers/cpufreq/cpufreq_ondemand.c | 24 +++++------------ drivers/cpufreq/cpufreq_performance.c | 14 ++-------- drivers/cpufreq/cpufreq_powersave.c | 18 +++---------- drivers/cpufreq/cpufreq_userspace.c | 18 +++---------- include/linux/cpufreq.h | 14 ++++++++++ kernel/sched/cpufreq_schedutil.c | 6 +---- 11 files changed, 62 insertions(+), 114 deletions(-)