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Uncore counters do not provide mechanisms like interrupts to report overflows and the accumulated user-visible count is incorrect if there is more than one overflow between two successive read requests for the same event because the value of prev_count goes out-of-date for calculating the correct delta. To avoid this, start a hrtimer to periodically initiate a pmu->read() of the active counters for keeping prev_count up-to-date. It should be noted that the hrtimer duration should be lesser than the shortest time it takes for a counter to overflow for this approach to be effective. Signed-off-by: Sandipan Das <sandipan.das@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/8ecf5fe20452da1cd19cf3ff4954d3e7c5137468.1744906694.git.sandipan.das@amd.com