| Message ID | 20220225082420.450620-1-shawn.guo@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | cpuidle: psci: Iterate backwards over list in psci_pd_remove() | expand |
On Fri, Feb 25, 2022 at 04:24:20PM +0800, Shawn Guo wrote: > In case that psci_pd_init_topology() fails for some reason, > psci_pd_remove() will be responsible for deleting provider and removing > genpd from psci_pd_providers list. There will be a failure when removing > the cluster PD, because the cpu (child) PDs haven't been removed. > > [ 0.050232] CPUidle PSCI: init PM domain cpu0 > [ 0.050278] CPUidle PSCI: init PM domain cpu1 > [ 0.050329] CPUidle PSCI: init PM domain cpu2 > [ 0.050370] CPUidle PSCI: init PM domain cpu3 > [ 0.050422] CPUidle PSCI: init PM domain cpu-cluster0 > [ 0.050475] PM: genpd_remove: unable to remove cpu-cluster0 > [ 0.051412] PM: genpd_remove: removed cpu3 > [ 0.051449] PM: genpd_remove: removed cpu2 > [ 0.051499] PM: genpd_remove: removed cpu1 > [ 0.051546] PM: genpd_remove: removed cpu0 > > Fix the problem by iterating the provider list in a reversely order, so s/reversely/reversed > that parent PD gets removed before child's PDs. s/before/after Essentially, with this change, the PM domains will be removed in the same order how they were added. [ 0.029052] CPUidle PSCI: init PM domain cpu0 [ 0.029076] CPUidle PSCI: init PM domain cpu1 [ 0.029103] CPUidle PSCI: init PM domain cpu2 [ 0.029124] CPUidle PSCI: init PM domain cpu3 [ 0.029151] CPUidle PSCI: init PM domain cpu-cluster0 [ 0.029647] PM: genpd_remove: removed cpu0 [ 0.029666] PM: genpd_remove: removed cpu1 [ 0.029690] PM: genpd_remove: removed cpu2 [ 0.029714] PM: genpd_remove: removed cpu3 [ 0.029738] PM: genpd_remove: removed cpu-cluster0 Shawn > > Signed-off-by: Shawn Guo <shawn.guo@linaro.org> > --- > drivers/cpuidle/cpuidle-psci-domain.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c > index ff2c3f8e4668..ce5c415fb04d 100644 > --- a/drivers/cpuidle/cpuidle-psci-domain.c > +++ b/drivers/cpuidle/cpuidle-psci-domain.c > @@ -182,7 +182,8 @@ static void psci_pd_remove(void) > struct psci_pd_provider *pd_provider, *it; > struct generic_pm_domain *genpd; > > - list_for_each_entry_safe(pd_provider, it, &psci_pd_providers, link) { > + list_for_each_entry_safe_reverse(pd_provider, it, > + &psci_pd_providers, link) { > of_genpd_del_provider(pd_provider->node); > > genpd = of_genpd_remove_last(pd_provider->node); > -- > 2.25.1 >
On Fri, Feb 25, 2022 at 04:24:20PM +0800, Shawn Guo wrote: > In case that psci_pd_init_topology() fails for some reason, > psci_pd_remove() will be responsible for deleting provider and removing > genpd from psci_pd_providers list. There will be a failure when removing > the cluster PD, because the cpu (child) PDs haven't been removed. > > [ 0.050232] CPUidle PSCI: init PM domain cpu0 > [ 0.050278] CPUidle PSCI: init PM domain cpu1 > [ 0.050329] CPUidle PSCI: init PM domain cpu2 > [ 0.050370] CPUidle PSCI: init PM domain cpu3 > [ 0.050422] CPUidle PSCI: init PM domain cpu-cluster0 > [ 0.050475] PM: genpd_remove: unable to remove cpu-cluster0 > [ 0.051412] PM: genpd_remove: removed cpu3 > [ 0.051449] PM: genpd_remove: removed cpu2 > [ 0.051499] PM: genpd_remove: removed cpu1 > [ 0.051546] PM: genpd_remove: removed cpu0 > > Fix the problem by iterating the provider list in a reversely order, so > that parent PD gets removed before child's PDs. > Makes sense. Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
On Fri, 25 Feb 2022 at 09:24, Shawn Guo <shawn.guo@linaro.org> wrote: > > In case that psci_pd_init_topology() fails for some reason, > psci_pd_remove() will be responsible for deleting provider and removing > genpd from psci_pd_providers list. There will be a failure when removing > the cluster PD, because the cpu (child) PDs haven't been removed. > > [ 0.050232] CPUidle PSCI: init PM domain cpu0 > [ 0.050278] CPUidle PSCI: init PM domain cpu1 > [ 0.050329] CPUidle PSCI: init PM domain cpu2 > [ 0.050370] CPUidle PSCI: init PM domain cpu3 > [ 0.050422] CPUidle PSCI: init PM domain cpu-cluster0 > [ 0.050475] PM: genpd_remove: unable to remove cpu-cluster0 > [ 0.051412] PM: genpd_remove: removed cpu3 > [ 0.051449] PM: genpd_remove: removed cpu2 > [ 0.051499] PM: genpd_remove: removed cpu1 > [ 0.051546] PM: genpd_remove: removed cpu0 > > Fix the problem by iterating the provider list in a reversely order, so > that parent PD gets removed before child's PDs. > > Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Thanks for fixing this! Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> I think we should add a fixes tag, like below and also tag this for stable kernels. Fixes: a65a397f2451 ("cpuidle: psci: Add support for PM domains by using genpd") Kind regards Uffe > --- > drivers/cpuidle/cpuidle-psci-domain.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c > index ff2c3f8e4668..ce5c415fb04d 100644 > --- a/drivers/cpuidle/cpuidle-psci-domain.c > +++ b/drivers/cpuidle/cpuidle-psci-domain.c > @@ -182,7 +182,8 @@ static void psci_pd_remove(void) > struct psci_pd_provider *pd_provider, *it; > struct generic_pm_domain *genpd; > > - list_for_each_entry_safe(pd_provider, it, &psci_pd_providers, link) { > + list_for_each_entry_safe_reverse(pd_provider, it, > + &psci_pd_providers, link) { > of_genpd_del_provider(pd_provider->node); > > genpd = of_genpd_remove_last(pd_provider->node); > -- > 2.25.1 >
diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c index ff2c3f8e4668..ce5c415fb04d 100644 --- a/drivers/cpuidle/cpuidle-psci-domain.c +++ b/drivers/cpuidle/cpuidle-psci-domain.c @@ -182,7 +182,8 @@ static void psci_pd_remove(void) struct psci_pd_provider *pd_provider, *it; struct generic_pm_domain *genpd; - list_for_each_entry_safe(pd_provider, it, &psci_pd_providers, link) { + list_for_each_entry_safe_reverse(pd_provider, it, + &psci_pd_providers, link) { of_genpd_del_provider(pd_provider->node); genpd = of_genpd_remove_last(pd_provider->node);
In case that psci_pd_init_topology() fails for some reason, psci_pd_remove() will be responsible for deleting provider and removing genpd from psci_pd_providers list. There will be a failure when removing the cluster PD, because the cpu (child) PDs haven't been removed. [ 0.050232] CPUidle PSCI: init PM domain cpu0 [ 0.050278] CPUidle PSCI: init PM domain cpu1 [ 0.050329] CPUidle PSCI: init PM domain cpu2 [ 0.050370] CPUidle PSCI: init PM domain cpu3 [ 0.050422] CPUidle PSCI: init PM domain cpu-cluster0 [ 0.050475] PM: genpd_remove: unable to remove cpu-cluster0 [ 0.051412] PM: genpd_remove: removed cpu3 [ 0.051449] PM: genpd_remove: removed cpu2 [ 0.051499] PM: genpd_remove: removed cpu1 [ 0.051546] PM: genpd_remove: removed cpu0 Fix the problem by iterating the provider list in a reversely order, so that parent PD gets removed before child's PDs. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> --- drivers/cpuidle/cpuidle-psci-domain.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)