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>> } >> >> +/* >> + * resctrl_kmode_online_cpu() - Program kernel mode association for @cpu >> + * @cpu: CPU that has just been brought online >> + * >> + * If assign_global_enable_per_cpu is active and the rdtgroup has an active >> + * kernel-mode association, add @cpu to kmode_cpu_mask and program the >> + * corresponding kernel mode association. >> + */ >> +static void resctrl_kmode_online_cpu(unsigned int cpu) >> +{ >> + struct rdtgroup *rdtgrp = resctrl_kcfg.active.k_rdtgrp; >> + bool assign_ctrl, assign_mon; >> + >> + if (resctrl_kcfg.active.kmode_cur != RESCTRL_ASSIGN_GLOBAL_ENABLE_PER_CPU || >> + !rdtgrp || !rdtgrp->kmode) >> + return; >> + >> + assign_ctrl = (resctrl_kcfg.active.ctrl_mode == KMODE_ASSIGN); >> + assign_mon = (resctrl_kcfg.active.mon_mode == KMODE_ASSIGN); >> + >> + cpumask_set_cpu(cpu, &rdtgrp->kmode_cpu_mask); >> + >> + resctrl_arch_configure_kmode(cpumask_of(cpu), rdtgrp->closid, assign_ctrl, >> + rdtgrp->mon.rmid, assign_mon, true); > > If I counted right, at end of this series, resctrl_arch_configure_kmode() is called > six times and _every_ call is preceded with the same two line pattern above: > > assign_ctrl = (resctrl_kcfg.active.ctrl_mode == KMODE_ASSIGN); > assign_mon = (resctrl_kcfg.active.mon_mode == KMODE_ASSIGN); > > Could this be simplified with a single helper that does something like: > > static void resctrl_configure_global_kmode(const struct cpumask *mask, > struct rdtgroup *rdtgrp, bool enable) > { > resctrl_arch_configure_global_kmode(mask, rdtgrp->closid, > resctrl_kcfg.active.ctrl_mode == KMODE_ASSIGN, > rdtgrp->mon.rmid, > resctrl_kcfg.active.mon_mode == KMODE_ASSIGN, > enable); > } > Sure. That will do. Thanks. > >> +} >> + >> +/* >> + * resctrl_kmode_offline_cpu() - Clear kernel mode association for @cpu >> + * @cpu: CPU being taken offline. >> + * >> + * If assign_global_enable_per_cpu is active, disable the kernel mode >> + * association for @cpu and remove it from kmode_cpu_mask. >> + */ >> +static void resctrl_kmode_offline_cpu(unsigned int cpu) >> +{ >> + struct rdtgroup *rdtgrp = resctrl_kcfg.active.k_rdtgrp; >> + bool assign_ctrl, assign_mon; >> + >> + if (resctrl_kcfg.active.kmode_cur != RESCTRL_ASSIGN_GLOBAL_ENABLE_PER_CPU || >> + !rdtgrp || !rdtgrp->kmode) >> + return; >> + >> + if (!cpumask_test_cpu(cpu, &rdtgrp->kmode_cpu_mask)) >> + return; >> + >> + assign_ctrl = (resctrl_kcfg.active.ctrl_mode == KMODE_ASSIGN); >> + assign_mon = (resctrl_kcfg.active.mon_mode == KMODE_ASSIGN); >> + >> + cpumask_clear_cpu(cpu, &rdtgrp->kmode_cpu_mask); >> + >> + resctrl_arch_configure_kmode(cpumask_of(cpu), rdtgrp->closid, assign_ctrl, >> + rdtgrp->mon.rmid, assign_mon, false); >> +} >> + >> void resctrl_online_cpu(unsigned int cpu) >> { >> mutex_lock(&rdtgroup_mutex); >> /* The CPU is set in default rdtgroup after online. */ >> cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask); >> + /* Program any active kernel mode association on this CPU. */ > > This comment is not helpful. Will remove these comments. Thanks Babu