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Ensure evsel->pmu matches the evsel->core.attr. Remove exclude bits that get set in other fallback attempts when switching the event. Log the event name with modifiers when switching the event on fallback. Signed-off-by: Ian Rogers Tested-by: Thomas Richter --- tools/perf/util/evsel.c | 45 ++++++++++++++++++++++++++++------------- tools/perf/util/evsel.h | 2 ++ 2 files changed, 33 insertions(+), 14 deletions(-) diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index f59228c1a39e..bd14d9bbc91f 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -3785,25 +3785,42 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err, { int paranoid; - if ((err == ENOENT || err == ENXIO || err == ENODEV) && - evsel->core.attr.type == PERF_TYPE_HARDWARE && - evsel->core.attr.config == PERF_COUNT_HW_CPU_CYCLES) { + if ((err == ENODEV || err == ENOENT || err == ENXIO) && + evsel__match(evsel, HARDWARE, HW_CPU_CYCLES)) { /* - * If it's cycles then fall back to hrtimer based cpu-clock sw - * counter, which is always available even if no PMU support. - * - * PPC returns ENXIO until 2.6.37 (behavior changed with commit - * b0a873e). + * If it's the legacy hardware cycles event fails then fall back + * to hrtimer based cpu-clock sw counter, which is always + * available even if no PMU support. PPC returned ENXIO rather + * than ENODEV or ENOENT until 2.6.37. */ - evsel->core.attr.type = PERF_TYPE_SOFTWARE; + evsel->pmu = perf_pmus__find_by_type(PERF_TYPE_SOFTWARE); + assert(evsel->pmu); /* software is a "well-known" and can't fail PMU type. */ + + /* Configure the event. */ + evsel->core.attr.type = PERF_TYPE_SOFTWARE; evsel->core.attr.config = target__has_cpu(target) ? PERF_COUNT_SW_CPU_CLOCK : PERF_COUNT_SW_TASK_CLOCK; - scnprintf(msg, msgsize, - "The cycles event is not supported, trying to fall back to %s", - target__has_cpu(target) ? "cpu-clock" : "task-clock"); + evsel->core.is_pmu_core = false; + + /* Remove excludes for new event. */ + if (evsel->fallenback_eacces) { + evsel->core.attr.exclude_kernel = 0; + evsel->core.attr.exclude_hv = 0; + evsel->fallenback_eacces = false; + } + if (evsel->fallenback_eopnotsupp) { + evsel->core.attr.exclude_guest = 0; + evsel->fallenback_eopnotsupp = false; + } + /* Name is recomputed by evsel__name. */ zfree(&evsel->name); + + /* Log message. */ + scnprintf(msg, msgsize, + "The cycles event is not supported, trying to fall back to %s", + evsel__name(evsel)); return true; } else if (err == EACCES && !evsel->core.attr.exclude_kernel && (paranoid = perf_event_paranoid()) > 1) { @@ -3830,7 +3847,7 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err, " samples", paranoid); evsel->core.attr.exclude_kernel = 1; evsel->core.attr.exclude_hv = 1; - + evsel->fallenback_eacces = true; return true; } else if (err == EOPNOTSUPP && !evsel->core.attr.exclude_guest && !evsel->exclude_GH) { @@ -3851,7 +3868,7 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err, /* Apple M1 requires exclude_guest */ scnprintf(msg, msgsize, "Trying to fall back to excluding guest samples"); evsel->core.attr.exclude_guest = 1; - + evsel->fallenback_eopnotsupp = true; return true; } no_fallback: diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index a3d754c029a0..97f57fab28ce 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -124,6 +124,8 @@ struct evsel { bool default_metricgroup; /* A member of the Default metricgroup */ bool default_show_events; /* If a default group member, show the event */ bool needs_uniquify; + bool fallenback_eacces; + bool fallenback_eopnotsupp; struct hashmap *per_pkg_mask; int err; int script_output_type; -- 2.53.0.851.ga537e3e6e9-goog