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but monitoring is inherited from the user task. > - GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU: Assigns a dedicated resource > allocation and monitoring for kernel work. > > Expose these modes during resource discovery when PLZA is available. > > Signed-off-by: Babu Moger > --- > v4: New patch to set the supported features during arch init. > --- > arch/x86/kernel/cpu/resctrl/core.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c > index 27e09cded829..df7e19fe6007 100644 > --- a/arch/x86/kernel/cpu/resctrl/core.c > +++ b/arch/x86/kernel/cpu/resctrl/core.c > @@ -962,6 +962,9 @@ static __init bool get_rdt_alloc_resources(void) > if (get_slow_mem_config()) > ret = true; > > + if (ret && rdt_cpu_has(X86_FEATURE_PLZA)) > + resctrl_set_kmode_support(GLOBAL_ASSIGN_CTRL_INHERIT_MON_PER_CPU); > + > return ret; > } > > @@ -988,6 +991,9 @@ static __init bool get_rdt_mon_resources(void) > if (!ret) > return false; > > + if (rdt_cpu_has(X86_FEATURE_PLZA)) > + resctrl_set_kmode_support(GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU); > + > return !rdt_get_l3_mon_config(r); > } > Sashiko reported: https://sashiko.dev/#/patchset/cover.1783461016.git.babu.moger%40amd.com?part=7 --- Patch [7]: [RESEND PATCH v4 07/15] x86/resctrl: Expose the supported PLZA kernel-mode policies during init --- commit 6d029d053cc0d67da93c0b4ae5419b85cfaeb5aa Author: Babu Moger x86/resctrl: Expose the supported PLZA kernel-mode policies during init This commit updates the generic resctrl subsystem to expose PLZA kernel-mode policies during resource discovery. When X86_FEATURE_PLZA is present, it sets up support for GLOBAL_ASSIGN_CTRL_INHERIT_MON_PER_CPU and GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU policies. > diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c > index 27e09cded8299..df7e19fe60078 100644 > --- a/arch/x86/kernel/cpu/resctrl/core.c > +++ b/arch/x86/kernel/cpu/resctrl/core.c [ ... ] > @@ -988,6 +991,9 @@ static __init bool get_rdt_mon_resources(void) > if (!ret) > return false; > > + if (rdt_cpu_has(X86_FEATURE_PLZA)) > + resctrl_set_kmode_support(GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU); Is it possible for GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU to be advertised here even if resource allocation features are disabled on the system? Because this policy assigns a dedicated resource allocation for kernel work, should this check verify rdt_alloc_capable before exposing the policy? If allocation is disabled via kernel command-line parameters (like rdt=!l3cat), but monitoring features are present, it seems like we might expose an allocation-dependent policy to userspace incorrectly. ------------------------------------------------------------------------ PLZA is really meaningful when allocation is enabled. I think it would be better to check rdt_alloc_capable before enabling GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU. Will add the check. if (rdt_alloc_capable && rdt_cpu_has(X86_FEATURE_PLZA)) resctrl_set_kmode_support(GLOBAL_ASSIGN_CTRL_ASSIGN_MON_PER_CPU); Thanks Babu