Merge branch 'tracing/core' into perf/core

Merge reason: to add event filter support we need the following
commits from the tracing tree:

 3f6fe06: tracing/filters: Unify the regex parsing helpers
 1889d20: tracing/filters: Provide basic regex support
 737f453: tracing/filters: Cleanup useless headers

Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --cc Documentation/kernel-parameters.txt
Simple merge

diff --cc arch/s390/kernel/ftrace.c
Simple merge

diff --cc kernel/trace/trace_events.c
Simple merge

diff --cc kernel/trace/trace_syscalls.c
Simple merge