From 71ad88efebbcde374bddf904b96f3a7fc82d45d4 Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Tue, 12 Nov 2013 17:58:48 +0100 Subject: perf: Add active_entry list head to struct perf_event This patch adds a new field to the struct perf_event. It is intended to be used to chain events which are active (enabled). It helps in the hardware layer for PMUs which do not have actual counter restrictions, i.e., free running read-only counters. Active events are chained as opposed to being tracked via the counter they use. To save space we use a union with hlist_entry as both are mutually exclusive (suggested by Jiri Olsa). Signed-off-by: Stephane Eranian Reviewed-by: Andi Kleen Signed-off-by: Peter Zijlstra Cc: acme@redhat.com Cc: jolsa@redhat.com Cc: zheng.z.yan@intel.com Cc: bp@alien8.de Cc: maria.n.dimakopoulou@gmail.com Link: http://lkml.kernel.org/r/1384275531-10892-2-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar --- include/linux/perf_event.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/linux/perf_event.h') diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 2e069d1288df..8f4a70f2eca8 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -319,7 +319,10 @@ struct perf_event { */ struct list_head migrate_entry; - struct hlist_node hlist_entry; + union { + struct hlist_node hlist_entry; + struct list_head active_entry; + }; int nr_siblings; int group_flags; struct perf_event *group_leader; -- cgit v1.2.3