perf session: Embed the host machine data on perf_session

We have just one host on a given session, and that is the most common
setup right now, so embed a ->host_machine struct machine instance
directly in the perf_session class, check if we're looking for it before
going to the rb_tree.

This also fixes a problem found when we try to process old perf.data
files where we didn't have MMAP events for the kernel and modules and
thus don't create the kernel maps, do it in event__preprocess_sample if
it wasn't already.

Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index f2b2c6a3a49d..eb9f179376a5 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -25,6 +25,7 @@ struct perf_session {
 	unsigned long		mmap_window;
 	struct rb_root		threads;
 	struct thread		*last_match;
+	struct machine		host_machine;
 	struct rb_root		machines;
 	struct events_stats	events_stats;
 	struct rb_root		stats_by_id;
@@ -107,18 +108,22 @@ int perf_session__browse_hists(struct rb_root *hists, u64 nr_hists,
 static inline
 struct machine *perf_session__find_host_machine(struct perf_session *self)
 {
-	return machines__find_host(&self->machines);
+	return &self->host_machine;
 }
 
 static inline
 struct machine *perf_session__find_machine(struct perf_session *self, pid_t pid)
 {
+	if (pid == HOST_KERNEL_ID)
+		return &self->host_machine;
 	return machines__find(&self->machines, pid);
 }
 
 static inline
 struct machine *perf_session__findnew_machine(struct perf_session *self, pid_t pid)
 {
+	if (pid == HOST_KERNEL_ID)
+		return &self->host_machine;
 	return machines__findnew(&self->machines, pid);
 }
 
@@ -126,14 +131,11 @@ static inline
 void perf_session__process_machines(struct perf_session *self,
 				    machine__process_t process)
 {
+	process(&self->host_machine, self);
 	return machines__process(&self->machines, process, self);
 }
 
-static inline
-size_t perf_session__fprintf_dsos(struct perf_session *self, FILE *fp)
-{
-	return machines__fprintf_dsos(&self->machines, fp);
-}
+size_t perf_session__fprintf_dsos(struct perf_session *self, FILE *fp);
 
 static inline
 size_t perf_session__fprintf_dsos_buildid(struct perf_session *self, FILE *fp,