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Sure. > >> associations than the originating user task. On x86, Privilege Level Zero >> Association (PLZA) enables the kernel to switch to a different CLOSID/RMID >> when entering kernel mode. >> >> Architectures need a common way to name kernel modes before resctrl >> can report what is active or what the platform supports. >> >> Introduce enum resctrl_kernel_mode: >> - RESCTRL_INHERIT_USER: Kernel mode inherits allocation and monitoring >> from the user task. >> - RESCTRL_ASSIGN_GLOBAL_ENABLE_PER_CPU: Kernel mode may use allocation >> and/or monitoring associations that differ from the user task. On x86, >> CLOSID and RMID can be configured independently for kernel mode. >> >> Signed-off-by: Babu Moger >> --- > > ... > >> --- >> include/linux/resctrl.h | 25 +++++++++++++++++++++++++ >> 1 file changed, 25 insertions(+) >> >> diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h >> index dd09c2ce9a0f..4245d1e65ccc 100644 >> --- a/include/linux/resctrl.h >> +++ b/include/linux/resctrl.h >> @@ -704,6 +704,31 @@ int resctrl_arch_io_alloc_enable(struct rdt_resource *r, bool enable); >> */ >> bool resctrl_arch_get_io_alloc_enabled(struct rdt_resource *r); >> >> +/** >> + * enum resctrl_kernel_mode - Kernel mode control and monitoring association. >> + * >> + * @RESCTRL_INHERIT_USER: >> + * Kernel mode inherits both allocation and monitoring associations >> + * from the user space task. On x86, kernel uses the same CLOSID and >> + * RMID as the user-space task. >> + * >> + * @RESCTRL_ASSIGN_GLOBAL_ENABLE_PER_CPU: >> + * Kernel mode may use allocation and monitoring associations that > > Why is this "may use"? Could this be made more accurate? Consider, for > example: > All kernel mode work uses the same allocation and/or monitoring > association via an assigned CTRL_MON or MON group. The mode can > be enabled/disabled per-CPU. When the mode is disabled on a CPU > then the kernel work on that CPU inherits the allocation and > monitoring association from the user space task, effectively the > kernel mode becomes RESCTRL_INHERIT_USER on that CPU. > Sure. Thanks. > >> + * differ from the user task. On x86, CLOSID and RMID are configured >> + * independently; either or both may differ from user mode. > > Please first provide all details that support what resctrl fs exposes to > user space before, if at all, adding any x86 specific details. > Sure. >> + * >> + * All online CPUs are included by default. A subset may be selected >> + * through the resctrl group interface, and a CTRL_MON or MON group >> + * may be associated with this mode. > > Please note that the word "associated" appears in multiple contexts here. "assigned" might work better here. > >> + */ >> +enum resctrl_kernel_mode { >> + RESCTRL_INHERIT_USER, >> + RESCTRL_ASSIGN_GLOBAL_ENABLE_PER_CPU, > > Something that stands out in this series is the multiple occurrences of > "assigned" in the new interface. What do you think of just dropping > "assign" from the kernel mode name? Actually, I was thinking about shortening the name here. Let's remove "assign" from here. Thanks Babu .