| Message ID | 20210323145608.29832-1-lukasz.luba@arm.com |
|---|---|
| State | Accepted |
| Commit | fb9d62b27ab1e07d625591549c314b7d406d21df |
| Headers | show |
| Series | PM / EM: postpone creating the debugfs dir till fs_initcall | expand |
On 3/23/21 3:26 PM, Greg KH wrote: > On Tue, Mar 23, 2021 at 02:56:08PM +0000, Lukasz Luba wrote: >> The debugfs directory '/sys/kernel/debug/energy_model' is needed before >> the Energy Model registration can happen. With the recent change in >> debugfs subsystem it's not allowed to create this directory at early stage >> (core_initcall). Thus creating this directory would fail. >> Postpone the creation of the EM debug dir to later stage: fs_initcall. >> It should be safe since all clients: CPUFreq drivers, Devfreq drivers will >> be initialized in later stages. >> The custom debug log below prints the time of creation the EM debug dir at >> fs_initcall and successful registration of EMs at later stages. >> >> [ 1.505717] energy_model: creating rootdir >> [ 3.698307] cpu cpu0: EM: created perf domain >> [ 3.709022] cpu cpu1: EM: created perf domain >> >> fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized") >> Reported-by: Ionela Voinescu <ionela.voinescu@arm.com> >> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> >> --- >> Hi Rafael, >> >> Please take this patch into your PM v5.12 fixes. The change described in >> the patch above landed in v5.12-rc1. Some of our EAS/EM tests are failing. > > Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Thank you Greg! Regards, Lukasz
On Tue, Mar 23, 2021 at 4:57 PM Lukasz Luba <lukasz.luba@arm.com> wrote: > > > > On 3/23/21 3:26 PM, Greg KH wrote: > > On Tue, Mar 23, 2021 at 02:56:08PM +0000, Lukasz Luba wrote: > >> The debugfs directory '/sys/kernel/debug/energy_model' is needed before > >> the Energy Model registration can happen. With the recent change in > >> debugfs subsystem it's not allowed to create this directory at early stage > >> (core_initcall). Thus creating this directory would fail. > >> Postpone the creation of the EM debug dir to later stage: fs_initcall. > >> It should be safe since all clients: CPUFreq drivers, Devfreq drivers will > >> be initialized in later stages. > >> The custom debug log below prints the time of creation the EM debug dir at > >> fs_initcall and successful registration of EMs at later stages. > >> > >> [ 1.505717] energy_model: creating rootdir > >> [ 3.698307] cpu cpu0: EM: created perf domain > >> [ 3.709022] cpu cpu1: EM: created perf domain > >> > >> fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized") > >> Reported-by: Ionela Voinescu <ionela.voinescu@arm.com> > >> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> > >> --- > >> Hi Rafael, > >> > >> Please take this patch into your PM v5.12 fixes. The change described in > >> the patch above landed in v5.12-rc1. Some of our EAS/EM tests are failing. > > > > Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > > > Thank you Greg! Applied as 5.12-rc material, thanks!
On 3/23/21 6:55 PM, Rafael J. Wysocki wrote: > On Tue, Mar 23, 2021 at 4:57 PM Lukasz Luba <lukasz.luba@arm.com> wrote: >> >> >> >> On 3/23/21 3:26 PM, Greg KH wrote: >>> On Tue, Mar 23, 2021 at 02:56:08PM +0000, Lukasz Luba wrote: >>>> The debugfs directory '/sys/kernel/debug/energy_model' is needed before >>>> the Energy Model registration can happen. With the recent change in >>>> debugfs subsystem it's not allowed to create this directory at early stage >>>> (core_initcall). Thus creating this directory would fail. >>>> Postpone the creation of the EM debug dir to later stage: fs_initcall. >>>> It should be safe since all clients: CPUFreq drivers, Devfreq drivers will >>>> be initialized in later stages. >>>> The custom debug log below prints the time of creation the EM debug dir at >>>> fs_initcall and successful registration of EMs at later stages. >>>> >>>> [ 1.505717] energy_model: creating rootdir >>>> [ 3.698307] cpu cpu0: EM: created perf domain >>>> [ 3.709022] cpu cpu1: EM: created perf domain >>>> >>>> fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized") >>>> Reported-by: Ionela Voinescu <ionela.voinescu@arm.com> >>>> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> >>>> --- >>>> Hi Rafael, >>>> >>>> Please take this patch into your PM v5.12 fixes. The change described in >>>> the patch above landed in v5.12-rc1. Some of our EAS/EM tests are failing. >>> >>> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> >>> >> >> Thank you Greg! > > Applied as 5.12-rc material, thanks! > Thank you Rafael! Regards, Lukasz
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c index 1358fa4abfa8..0f4530b3a8cd 100644 --- a/kernel/power/energy_model.c +++ b/kernel/power/energy_model.c @@ -98,7 +98,7 @@ static int __init em_debug_init(void) return 0; } -core_initcall(em_debug_init); +fs_initcall(em_debug_init); #else /* CONFIG_DEBUG_FS */ static void em_debug_create_pd(struct device *dev) {} static void em_debug_remove_pd(struct device *dev) {}
The debugfs directory '/sys/kernel/debug/energy_model' is needed before the Energy Model registration can happen. With the recent change in debugfs subsystem it's not allowed to create this directory at early stage (core_initcall). Thus creating this directory would fail. Postpone the creation of the EM debug dir to later stage: fs_initcall. It should be safe since all clients: CPUFreq drivers, Devfreq drivers will be initialized in later stages. The custom debug log below prints the time of creation the EM debug dir at fs_initcall and successful registration of EMs at later stages. [ 1.505717] energy_model: creating rootdir [ 3.698307] cpu cpu0: EM: created perf domain [ 3.709022] cpu cpu1: EM: created perf domain fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized") Reported-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> --- Hi Rafael, Please take this patch into your PM v5.12 fixes. The change described in the patch above landed in v5.12-rc1. Some of our EAS/EM tests are failing. Regards, Lukasz kernel/power/energy_model.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)