On Tue, May 18, 2021 at 11:55 AM Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote: > > On Tue, May 18, 2021 at 11:52 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > > > On Mon, May 17, 2021 at 07:02:00PM -0700, Suren Baghdasaryan wrote: > > > > > diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c > > > index cc25a3cff41f..4b8e72640ac9 100644 > > > --- a/kernel/sched/psi.c > > > +++ b/kernel/sched/psi.c > > > @@ -148,6 +148,7 @@ > > > static int psi_bug __read_mostly; > > > > > > DEFINE_STATIC_KEY_FALSE(psi_disabled); > > > +DEFINE_STATIC_KEY_FALSE(psi_cgroups_disabled); > > > > I'm thinking the whole thing will be easier/clearer when you make this: > > > > DEFINE_STATIC_KEY_TRUE(psi_cgroups_enabled); > > > > Sounds good. Will respin another version. Thanks for reviewing! v3 is posted at https://lore.kernel.org/patchwork/patch/1435705 > > > > > > > > #ifdef CONFIG_PSI_DEFAULT_DISABLED > > > static bool psi_enable; > > > @@ -211,6 +212,9 @@ void __init psi_init(void) > > > return; > > > } > > > > > > + if (!cgroup_psi_enabled()) > > > + static_branch_enable(&psi_cgroups_disabled); > > > > if (!cgroup_psi_enabled()) > > static_branch_disable(&psi_cgroups_enabled); > > > > > + > > > psi_period = jiffies_to_nsecs(PSI_FREQ); > > > group_init(&psi_system); > > > } > > > @@ -744,23 +748,23 @@ static void psi_group_change(struct psi_group *group, int cpu, > > > > > > static struct psi_group *iterate_groups(struct task_struct *task, void **iter) > > > { > > > + if (*iter == &psi_system) > > > + return NULL; > > > + > > > #ifdef CONFIG_CGROUPS > > > + if (!static_branch_likely(&psi_cgroups_disabled)) { > > > > if (static_branch_likely(&psi_cgroups_enabled)) { > > > > > + struct cgroup *cgroup = NULL; > > > > > > + if (!*iter) > > > + cgroup = task->cgroups->dfl_cgrp; > > > + else > > > + cgroup = cgroup_parent(*iter); > > > > > > + if (cgroup && cgroup_parent(cgroup)) { > > > + *iter = cgroup; > > > + return cgroup_psi(cgroup); > > > + } > > > } > > > #endif > > > *iter = &psi_system; > > > return &psi_system; > > > > But yes, very nice. > > > > -- > > To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@xxxxxxxxxxx. > >
