On Mon, May 29, 2017 at 12:15:14PM +0300, Alexey Budankov wrote: > On 29.05.2017 10:46, Peter Zijlstra wrote: > > On Sat, May 27, 2017 at 02:19:51PM +0300, Alexey Budankov wrote:
> > > @@ -742,7 +772,17 @@ struct perf_event_context { > > > > > > struct list_head active_ctx_list; > > > struct list_head pinned_groups; > > > + /* > > > + * Cpu tree for pinned groups; keeps event's group_node nodes > > > + * of attached flexible groups; > > > + */ > > > + struct rb_root pinned_tree; > > > struct list_head flexible_groups; > > > + /* > > > + * Cpu tree for flexible groups; keeps event's group_node nodes > > > + * of attached flexible groups; > > > + */ > > > + struct rb_root flexible_tree; > > > struct list_head event_list; > > > int nr_events; > > > int nr_active; > > > @@ -758,6 +798,7 @@ struct perf_event_context { > > > */ > > > u64 time; > > > u64 timestamp; > > > + struct perf_event_tstamp tstamp_data; > > > > > > /* > > > * These fields let us detect when two contexts have both > > > > > > So why do we now have a list _and_ a tree for the same entries? > We need groups list to iterate through all groups configured for collection > and we need the tree to quickly iterate through the groups allocated for a > particular CPU only. *confused*, what? Why can't the tree do both?