perf parse-events: Prefer sysfs/JSON hardware events over legacy
It was requested that RISC-V be able to add events to the perf tool so the PMU driver didn't need to map legacy events to config encodings: https://lore.kernel.org/lkml/20240217005738.3744121-1-atishp@rivosinc.com/ This change makes the priority of events specified without a PMU the same as those specified with a PMU, namely sysfs and JSON events are checked first before using the legacy encoding. The hw_term is made more generic as a hardware_event that encodes a pair of string and int value, allowing parse_events_multi_pmu_add to fall back on a known encoding when the sysfs/JSON adding fails for core events. As this covers PE_VALUE_SYM_HW, that token is removed and related code simplified. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Tested-by: Atish Patra <atishp@rivosinc.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Beeman Strong <beeman@rivosinc.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20240416061533.921723-10-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>