The new pmu::event_terminate allows a PMU to access an event's cgroup before the event is torn down.
Used in CMT to dettach the cgroup from a monr before perf clears event->cgrp. Signed-off-by: David Carrillo-Cisneros <[email protected]> --- include/linux/perf_event.h | 6 ++++++ kernel/events/core.c | 4 ++++ 2 files changed, 10 insertions(+) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 406119b..14dff7a 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -298,6 +298,12 @@ struct pmu { int (*event_init) (struct perf_event *event); /* + * Terminate the event for this PMU. Optional complement for a + * successful event_init. Called before the event fields are tear down. + */ + void (*event_terminate) (struct perf_event *event); + + /* * Notification that the event was mapped or unmapped. Called * in the context of the mapping task. */ diff --git a/kernel/events/core.c b/kernel/events/core.c index 0de3ca5..464f46d 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4005,6 +4005,8 @@ static void _free_event(struct perf_event *event) ring_buffer_attach(event, NULL); mutex_unlock(&event->mmap_mutex); } + if (event->pmu->event_terminate) + event->pmu->event_terminate(event); if (is_cgroup_event(event)) perf_detach_cgroup(event); @@ -9226,6 +9228,8 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, exclusive_event_destroy(event); err_pmu: + if (event->pmu->event_terminate) + event->pmu->event_terminate(event); if (event->destroy) event->destroy(event); module_put(pmu->module); -- 2.8.0.rc3.226.g39d4020
