perf tests: Add framework for automated perf_event_attr tests

The idea is run perf session with kidnapping sys_perf_event_open
function. For each sys_perf_event_open call we store the perf_event_attr
data to the file to be checked later against what we expect.

You can run this by:
  $ python ./tests/attr.py -d ./tests/attr/ -p ./perf -v

v2 changes:
  - preserve errno value in the hook

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20121031145247.GB1027@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index e9683738d89f..a0ae2902f9c9 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -484,6 +484,8 @@ int main(int argc, const char **argv)
         }
         cmd = argv[0];
 
+        test_attr__init();
+
         /*
          * We use PATH to find perf commands, but we prepend some higher
          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH