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AMD PLZA (Privilege Level Zero >> Association) is the x86 feature that allows kernel traffic to use an >> assigned CLOSID alone or CLOSID and RMID together. >> >> Report the available kernel-modes when x86 PLZA is enabled. >> >> Signed-off-by: Babu Moger >> --- >> v3: New patch to report all the supported kernel mode by arch. >> --- >> arch/x86/kernel/cpu/resctrl/core.c | 15 +++++++++++++++ >> 1 file changed, 15 insertions(+) >> >> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c >> index 4a8717157e3e..699d8bb82875 100644 >> --- a/arch/x86/kernel/cpu/resctrl/core.c >> +++ b/arch/x86/kernel/cpu/resctrl/core.c >> @@ -894,6 +894,21 @@ bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt) >> } >> } >> >> +/** >> + * resctrl_arch_get_kmode_support() - x86: record which kernel-mode policies hardware supports >> + * @kcfg: Cumulative snapshot; OR bits into @kcfg->kmode (see &struct resctrl_kmode_cfg). > > If this is intended to be a cumulative snapshot this is a very subtle requirement > for architectures to "do the right thing" here. To make this more robust I think it will be > simpler if resctrl fs boots with resctrl_kcfg initialized to expected defaults. > Instead of this callback resctrl can add resctrl_set_kmode_support(u32 kmodes) > that the architecture *may* use to further initialize the kmodes supported by it. This > function is implemented by resctrl fs, instead of architecture, and it can fail if > architecture does not support INHERIT_CTRL_AND_MON. This will help to keep > struct resctrl_kmode_cfg private to resctrl fs while enforcing any assumptions about > which modes are required to be supported. Yes, agreed. I will move resctrl_set_kmode_support() to the FS layer and have the architecture code invoke it when setting the kmodes. That will make the struct resctrl_kmode_cfg private to FS layer. Thanks Babu