perf/x86/intel: Filter unsupported Topdown metrics event
Intel Sapphire Rapids server will introduce 8 metrics events. Intel Ice Lake only supports 4 metrics events. A perf tool user may mistakenly use the unsupported events via RAW format on Ice Lake. The user can still get a value from the unsupported Topdown metrics event once the following Sapphire Rapids enabling patch is applied. To enable the 8 metrics events on Intel Sapphire Rapids, the INTEL_TD_METRIC_MAX has to be updated, which impacts the is_metric_event(). The is_metric_event() is a generic function. On Ice Lake, the newly added SPR metrics events will be mistakenly accepted as metric events on creation. At runtime, the unsupported Topdown metrics events will be updated. Add a variable num_topdown_events in x86_pmu to indicate the available number of the Topdown metrics event on the platform. Apply the number into is_metric_event(). Only the supported Topdown metrics events should be created as metrics events. Apply the num_topdown_events in icl_update_topdown_event() as well. The function can be reused by the following patch. Suggested-by:Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by:
Kan Liang <kan.liang@linux.intel.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/1611873611-156687-4-git-send-email-kan.liang@linux.intel.com
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