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Suchit KarunakaranandArnaldo Carvalho de Melo
824b18f607
update_lock_stat() handles lock contentions that start but never reach a contention_end event (e.g., locks still held when profiling stops), but previously treated LOCK_AGGR_CGROUP as a no-op due to missing cgroup context in userspace. Fix this by adding a cgroup_id field to struct tstamp_data, recording it at contention_begin using get_current_cgroup_id() when aggr_mode is LOCK_AGGR_CGROUP. Capturing it at contention_begin is semantically correct, the contention cost is incurred by the task that had to wait, not by whatever task happens to be running at contention_end. It is also preferable from a performance standpoint, as contention_end runs just before the task enters the critical section. Update contention_end to use pelem->cgroup_id instead of calling get_current_cgroup_id() dynamically, ensuring both complete and incomplete contention events attribute the wait time to the cgroup at wait-start time consistently. Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tycho Andersen (AMD) <tycho@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>