perf session: Remove sample_type_check from event_ops

This is really something tools need to do before asking for the
events to be processed, leaving perf_session__process_events to
do just that, process events.

Also add a msg parameter to perf_session__has_traces() so that
the right message can be printed, fixing a regression added by
me in the previous cset (right timechart message) and also
fixing 'perf kmem', that was not asking if 'perf kmem record'
was ran.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1261957026-15580-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 7 insertions, 12 deletions

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 60eab8b3ff3..bc84a521795 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -73,6 +73,8 @@ struct perf_session *perf_session__new(const char *filename, int mode, bool forc
 
         if (mode == O_RDONLY && perf_session__open(self, force) < 0)
                 goto out_delete;
+
+        self->sample_type = perf_header__sample_type(&self->header);
 out:
         return self;
 out_free:
@@ -302,11 +304,6 @@ int perf_session__process_events(struct perf_session *self,
         page_size = getpagesize();
 
         head = self->header.data_offset;
-        self->sample_type = perf_header__sample_type(&self->header);
-
-        err = -EINVAL;
-        if (ops->sample_type_check && ops->sample_type_check(self) < 0)
-                goto out_err;
 
         if (!ops->full_paths) {
                 char bf[PATH_MAX];
@@ -394,13 +391,12 @@ out_err:
         return err;
 }
 
-int perf_session__has_traces(struct perf_session *self)
+bool perf_session__has_traces(struct perf_session *self, const char *msg)
 {
         if (!(self->sample_type & PERF_SAMPLE_RAW)) {
-                pr_err("No trace sample to read. Did you call perf record "
-                       "without -R?");
-                return -1;
+                pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg);
+                return false;
         }
 
-        return 0;
+        return true;
 }
diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index a6951d2f700..5771ccb3fe0 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -40,7 +40,6 @@ struct perf_event_ops {
         event_op        process_read_event;
         event_op        process_throttle_event;
         event_op        process_unthrottle_event;
-        int             (*sample_type_check)(struct perf_session *session);
         unsigned long   total_unknown;
         bool            full_paths;
 };
@@ -56,7 +55,7 @@ struct symbol **perf_session__resolve_callchain(struct perf_session *self,
                                                 struct ip_callchain *chain,
                                                 struct symbol **parent);
 
-int perf_session__has_traces(struct perf_session *self);
+bool perf_session__has_traces(struct perf_session *self, const char *msg);
 
 int perf_header__read_build_ids(int input, u64 offset, u64 file_size);