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Added all the code inline. We dont >>      need to separate this as arch code. >> >> v3: Removed changes related to mon_features. >>      Moved rdt_cpu_has to core.c and added new function >> resctrl_arch_has_abmc. >>      Also moved the fields mbm_assign_capable and mbm_assign_cntrs to >>      rdt_resource. (James) >> >> v2: Changed the field name to mbm_assign_capable from abmc_capable. >> --- >>   arch/x86/kernel/cpu/resctrl/monitor.c | 12 ++++++++++++ >>   include/linux/resctrl.h               |  4 ++++ >>   2 files changed, 16 insertions(+) >> >> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c >> b/arch/x86/kernel/cpu/resctrl/monitor.c >> index 795fe91a8feb..88312b5f0069 100644 >> --- a/arch/x86/kernel/cpu/resctrl/monitor.c >> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c >> @@ -1229,6 +1229,18 @@ int __init rdt_get_mon_l3_config(struct >> rdt_resource *r) >>               mbm_local_event.configurable = true; >>               mbm_config_rftype_init("mbm_local_bytes_config"); >>           } >> + >> +        if (rdt_cpu_has(X86_FEATURE_ABMC)) { >> +            r->mon.mbm_cntr_assignable = true; >> +            /* >> +             * Query CPUID_Fn80000020_EBX_x05 for number of >> +             * ABMC counters. >> +             */ > > At this point this comment seems unnecessary. Not an issue, it can stay of > you > prefer. > >> +            cpuid_count(0x80000020, 5, &eax, &ebx, &ecx, &edx); >> +            r->mon.num_mbm_cntrs = (ebx & 0xFFFF) + 1; >> +            if (WARN_ON(r->mon.num_mbm_cntrs > 64)) > > Please document where this "64" limit comes from. This is potentially a > problem > since the resctrl fs managed bitmap is hardcoded to be of size 64 but the > arch code > sets how many counters are supported. Will comment more later on bitmap > portions, but > to handle this I expect resctrl fs should at least sanity check the number > of counters > before attempting to initialize its bitmap ... or better, as James > suggests, make the > bitmap creation dynamic. Yes. Agree. It is better we allocate it dynamically. Then we don't need WARN_ON here. > >> +                r->mon.num_mbm_cntrs = 64; >> +        } >>       } >>         l3_mon_evt_init(r); >> diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h >> index 1097559f4987..72c498deeb5e 100644 >> --- a/include/linux/resctrl.h >> +++ b/include/linux/resctrl.h >> @@ -185,10 +185,14 @@ enum resctrl_scope { >>   /** >>    * struct resctrl_mon - Monitoring related data >>    * @num_rmid:        Number of RMIDs available >> + * @num_mbm_cntrs:    Number of monitoring counters >> + * @mbm_cntr_assignable:Is system capable of supporting monitor >> assignment? >>    * @evt_list:        List of monitoring events >>    */ >>   struct resctrl_mon { >>       int            num_rmid; >> +    int            num_mbm_cntrs; >> +    bool            mbm_cntr_assignable; >>       struct list_head    evt_list; >>   }; >>   > > Reinette > -- Thanks Babu Moger