Print additional 'preempt' tag for PERF_RECORD_SWITCH[_CPU_WIDE] OUT records when
event header misc field contains PERF_RECORD_MISC_SWITCH_OUT_PREEMPT bit set
designating preemption context switch out event:

tools/perf/perf report -D -i perf.data | grep _SWITCH

0 768361415226 0x27f076 [0x28]: PERF_RECORD_SWITCH_CPU_WIDE IN           prev pid/tid:     8/8
4 768362216813 0x28f45e [0x28]: PERF_RECORD_SWITCH_CPU_WIDE OUT          next pid/tid:     0/0
4 768362217824 0x28f486 [0x28]: PERF_RECORD_SWITCH_CPU_WIDE IN           prev pid/tid:  4073/4073
0 768362414027 0x27f0ce [0x28]: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt  next pid/tid:     8/8
0 768362414367 0x27f0f6 [0x28]: PERF_RECORD_SWITCH_CPU_WIDE IN           prev pid/tid:     0/0
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/6f5aebb9-b96c-f304-f08f-8f046d38de4f@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>