[PATCH v3 0/3] perf evsel fallback changes

Ian Rogers
2026-03-13T20:28:17Z

Discussion with Thomas Richter in:
https://lore.kernel.org/lkml/20260306071002.2526085-1-tmricht@linux.ibm.com/
showed that the evsel__fallback wasn't working for s390. These patches
avoid the problematic frame pointer callchain on s390 and fix
evsel__fallback from a range of problems when falling back to a
software event. I simulated failures when developing the patches but
they are untested other than that.

v3: Incorporate feedback about event and callchain behavior for s390:
https://lore.kernel.org/lkml/20260312061628.1593105-1-irogers@google.com/

v2: try exclude_callchain_user for s390 rather than fully disabling
the callchain. Fix a missed clearing of is_pmu_core if the
software event fallback.
https://lore.kernel.org/lkml/20260312061628.1593105-1-irogers@google.com/

v1: https://lore.kernel.org/lkml/20260312031928.1494864-1-irogers@google.com/

Ian Rogers (3):
perf evsel: Improve falling back from cycles
perf target: Constify simple check functions
perf evlist: Improve default event for s390

tools/perf/builtin-record.c | 3 +-
tools/perf/builtin-top.c | 2 +-
tools/perf/tests/event_update.c | 4 ++-
tools/perf/tests/expand-cgroup.c | 4 ++-
tools/perf/tests/perf-record.c | 7 ++--
tools/perf/tests/topology.c | 4 ++-
tools/perf/util/evlist.c | 37 ++++++++++++---------
tools/perf/util/evlist.h | 2 +-
tools/perf/util/evsel.c | 56 +++++++++++++++++++++++---------
tools/perf/util/evsel.h | 2 ++
tools/perf/util/target.h | 12 +++----
11 files changed, 88 insertions(+), 45 deletions(-)

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2.53.0.851.ga537e3e6e9-goog