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> void resctrl_arch_configure_kmode(const struct cpumask *cpu_mask, > u32 closid, u32 rmid, bool enable); > > but only implemented under arch/x86/. ARM MPAM selects > CONFIG_RESCTRL_FS, so fs/resctrl/rdtgroup.c is compiled on aarch64 > and the linker fails: > > ld: fs/resctrl/rdtgroup.o: in function `rdtgroup_config_kmode_clear': > rdtgroup.c: undefined reference to `resctrl_arch_configure_kmode' > ld: fs/resctrl/rdtgroup.o: in function `resctrl_init': > rdtgroup.c: undefined reference to `resctrl_arch_get_kmode_support' > > Other arch-specific functions already have empty stubs in > drivers/resctrl/mpam_resctrl.c, e.g.: > > int resctrl_arch_io_alloc_enable(struct rdt_resource *r, bool enable) > { > return -EOPNOTSUPP; > } > > Adding the same for the two kmode functions would fix the build. Good catch. Will add in empty stubs in next revision for these 3 functions. > > 2) info/kernel_mode visible on non-PLZA platforms > > The "kernel_mode" entry is registered with fflags = RFTYPE_TOP_INFO: > > { > .name = "kernel_mode", > .mode = 0644, > ... > .fflags = RFTYPE_TOP_INFO, > }, > > This makes the file appear unconditionally under info/ -- even on > platforms without PLZA (ARM MPAM, older AMD/Intel without > X86_FEATURE_PLZA). On those platforms the file only shows the > default inherit_ctrl_and_mon mode, which is confusing since there > are no other modes to switch to. This is expected. We intended to expose the info/kernel_mode file for all architectures, and it will display the default mode inherit_ctrl_and_mon. This approach was also suggested by Reinette. https://lore.kernel.org/lkml/2ab556af-095b-422b-9396-f845c6fd0342@intel.com/ Thanks Babu