[tip:perf/core] perf evsel: Fix ftrace:function event recording

[tip-bot for Jiri Olsa <tipbot@zytor.com>]

Commit-ID:  f140373bc904d9541e3f8e985d3810864e34c735
Gitweb:     http://git.kernel.org/tip/f140373bc904d9541e3f8e985d3810864e34c735
Author:     Jiri Olsa <jolsa@kernel.org>
AuthorDate: Thu, 13 Nov 2014 18:21:03 +0100
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 19 Nov 2014 12:33:48 -0300

perf evsel: Fix ftrace:function event recording

Following patch fails (-EINVAL) ftrace:function with enabled user
space callchains:
  cfa77bc4af2c perf: Disallow user-space callchains for function trace events

We need to follow in perf tool itself and explicitly set the
perf_event_attr::exclude_callchain_user flag for ftrace:function
event.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1415899263-24820-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/evsel.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 34344ff..f2dc91f 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -658,6 +658,14 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
 		attr->mmap_data = track;
 	}
 
+	/*
+	 * We don't allow user space callchains for  function trace
+	 * event, due to issues with page faults while tracing page
+	 * fault handler and its overall trickiness nature.
+	 */
+	if (perf_evsel__is_function_event(evsel))
+		evsel->attr.exclude_callchain_user = 1;
+
 	if (callchain_param.enabled && !evsel->no_aux_samples)
 		perf_evsel__config_callgraph(evsel);