3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Olsa <jolsa@xxxxxxxxxx> commit 0231bb5336758426b44ccd798ccd3c5419c95d58 upstream. When we have group with mixed events (hw/sw) we want to end up with group leader being in hw context. So if group leader is initialy sw event, we move all the events under hw context. The move is done for each event by removing it from its context and adding it back into proper one. As a part of the removal the event is automatically disabled, which is not what we want at this stage of creating groups. The fix is to initialize event state after removal from sw context. This fix resulted from the following discussion: http://thread.gmane.org/gmane.linux.kernel.perf.user/1144 Reported-by: Andreas Hollmann <hollmann@xxxxxxxxx> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Corey Ashford <cjashfor@xxxxxxxxxxxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Vince Weaver <vince@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1359714225-4231-1-git-send-email-jolsa@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Li Zefan <lizefan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/events/core.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -839,6 +839,15 @@ list_add_event(struct perf_event *event, } /* + * Initialize event state based on the perf_event_attr::disabled. + */ +static inline void perf_event__state_init(struct perf_event *event) +{ + event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : + PERF_EVENT_STATE_INACTIVE; +} + +/* * Called at perf_event creation and when events are attached/detached from a * group. */ @@ -6241,8 +6250,7 @@ perf_event_alloc(struct perf_event_attr event->overflow_handler = overflow_handler; - if (attr->disabled) - event->state = PERF_EVENT_STATE_OFF; + perf_event__state_init(event); pmu = NULL; @@ -6616,9 +6624,17 @@ SYSCALL_DEFINE5(perf_event_open, mutex_lock(&gctx->mutex); perf_remove_from_context(group_leader); + + /* + * Removing from the context ends up with disabled + * event. What we want here is event in the initial + * startup state, ready to be add into new context. + */ + perf_event__state_init(group_leader); list_for_each_entry(sibling, &group_leader->sibling_list, group_entry) { perf_remove_from_context(sibling); + perf_event__state_init(sibling); put_ctx(gctx); } mutex_unlock(&gctx->mutex); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html