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What a strategy! I mentioned a couple of times that this is >>>>> >>>>> Agreed. >>>>> >>>>>> misleading. Since you insist on proclaiming "we cannot break pqos!" as >>>>>> motivation for this change you have to also disclose the consequence of >>>>>> this change on pqos followed by motivation why that is acceptable. Specifically: >>>>>> >>>>>>      https://lore.kernel.org/lkml/77f77d02-fae7-401d-9bb5- c62b244d23cd@intel.com/ >>>>> >>>>> I can provide output that demonstrates the issue, where the event counters report zeros. However, we won't observe the large counter values because the hardware resets the counters after reallocation. >>>>> >>>>> Will that be ok? >>>> >>>> No. This is not about hardware resetting the counters. This is about pqos not handling >>>> text return values, for example "Unavailable" and "Unassigned". This patch only >>>> focuses on pqos treating "Unassigned" as 0, but in "default" mode "Unavailable" will >>>> be encountered and pqos treating it as 0 is more severe. >>>> >>>> Consider a scenario where a counter is re-assigned. When user space reads the event >>>> value then it may see: >>>> >>>> , , , , ... >>>> >>>> "B" is computed by adding the new hardware counter value to A. As you indicate, hardware >>>> did reset the counter after re-allocation but that only means that "B" is no longer >>>> accurate. "B" is still returned and it is still larger than "A". >>>> >>>> Based on above, pqos sees: >>>> A, 0, B, 0, ... >>>> >>>> These jumps between bandwidth counts and zero is what pqos perceives as wraparound that is >>>> presented in the example: >>>> >>>>     https://lore.kernel.org/lkml/77f77d02-fae7-401d-9bb5- c62b244d23cd@intel.com/ >>> >>> Got it. I can add the output of the issue. Something like this. >>> >>> TIME 2026-09-15 00:53:46 >>> CORE     IPC      MISSES     LLC[KB]   MBL[MB/s]   MBR[MB/s] >>> 0        0.76         60k        32.0         0.0         0.0 >>> 1        0.45          1k        32.0         0.0         0.0 >>> 2        1.57        107k        64.0         0.0 17592186044184.9 >>> 3        1.62        276k      4928.0         3.2         0.5 >>> 4        0.53          1k       160.0         0.0         0.0 >>> 5        0.63         39k      1664.0         0.2         0.0 >>> 6        0.44          6k       128.0         0.0         0.0 >>> 7        0.50          1k       320.0         0.0         0.0 > > This would demonstrate how the change impacts pqos. Since the spirit of the > changelog continues to be "resctrl should not break pqos" it should motivate > why incorrect wraparound like above is more acceptable than returning 0 MB/s > when counters are not assigned. Will do. Thanks Babu