perf/x86/intel: Use context switch callback to flush LBR stack

Previous commit introduces context switch callback, its function
overlaps with the flush branch stack callback. So we can use the
context switch callback to flush LBR stack.

This patch adds code that uses the flush branch callback to
flush the LBR stack when task is being scheduled in. The callback
is enabled only when there are events use the LBR hardware. This
patch also removes all old flush branch stack code.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: eranian@google.com
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1415156173-10035-4-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 0 insertions, 1 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index fbab6235d053..c7007a564440 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -511,7 +511,6 @@ struct perf_event_context {
         u64                             generation;
         int                             pin_count;
         int                             nr_cgroups;      /* cgroup evts */
-        int                             nr_branch_stack; /* branch_stack evt */
         struct rcu_head                 rcu_head;
 
         struct delayed_work             orphans_remove;