Hi Babu, On 5/22/25 8:44 AM, Moger, Babu wrote: > On 5/21/25 18:03, Reinette Chatre wrote: ... >> This is why I proposed in [3] that the name of the mode reflects how user can interact >> with the system. Instead of one "mbm_cntr_assign" mode there can be "mbm_cntr_event_assign" >> that is used for ABMC and "mbm_cntr_group_assign" that is used for soft-ABMC. The mode should >> make it clear what the system is capable of wrt counter assignments. > > Yes, that makes sense. Perhaps we can also simplify it further: > > # cat /sys/fs/resctrl/info/L3_MON/mbm_assign_mode: > [mbm_cntr_evt_assign] <- for ABMC > mbm_cntr_grp_assign <- for soft-ABMC Looks good to me. Thank you. >> Considering this the interface should be clear: >> num_mbm_cntrs: reflects the number of counters in each domain that can be assigned. In >> "mbm_cntr_event_assign" this will be the number of counters that can be assigned to >> each event within a monitoring group, in "mbm_cntr_group_assign" this will be the number >> of counters that can be assigned to entire monitoring groups impacting all MBM events. >> >> mbm_L3_assignments: manages the counter assignment in each group. When user knows the mode >> is "mbm_cntr_event_assign"/"mbm_cntr_group_assign" then it should be clear to user space how the >> interface behaves wrt assignment, no surprises of multiple events impacted when >> assigning/unassigning single event. >> >> For soft-ABMC I thus find it most intuitive for num_mbm_cntrs to be the exact number >> of "active" RMIDs that the system can support *and* changing the name of the modes >> to help user interpret num_mbm_cntrs. > > Sure. The option A: fits well here then. > > Option A (counters are RMIDs): > # cat /sys/fs/resctrl/info/L3_MON/num_mbm_cntrs > 0=31;1=31 Thank you for considering. Please add the requirements from this discussion to your running list. Also please keep in mind how soft-ABMC intends to use the interfaces created by this work so that the documentation that accompanies the ABMC support in this series leaves enough "wiggle room" for soft-ABMC to be built on top. >>> [1] https://lore.kernel.org/lkml/CALPaoChSzzU5mzMZsdT6CeyEn0WD1qdT9fKCoNW_ty4tojtrkw@xxxxxxxxxxxxxx/ >> >> Reinette >> >> [2] https://lore.kernel.org/lkml/b9e48e8f-3035-4a7e-a983-ce829bd9215a@xxxxxxxxx/ >> [3] https://lore.kernel.org/lkml/b3babdac-da08-4dfd-9544-47db31d574f5@xxxxxxxxx/ >> > Reinette
