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, 10 insertions, 0 deletions

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index dfc8bf64d70f..d2ea9dd9fdf1 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -656,6 +656,16 @@ int event__preprocess_sample(const event_t *self, struct perf_session *session,
                 goto out_filtered;
 
         dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
+        /*
+         * Have we already created the kernel maps for the host machine?
+         *
+         * This should have happened earlier, when we processed the kernel MMAP
+         * events, but for older perf.data files there was no such thing, so do
+         * it now.
+         */
+        if (cpumode == PERF_RECORD_MISC_KERNEL &&
+            session->host_machine.vmlinux_maps[MAP__FUNCTION] == NULL)
+                machine__create_kernel_maps(&session->host_machine);
 
         thread__find_addr_map(thread, session, cpumode, MAP__FUNCTION,
                               self->ip.pid, self->ip.ip, al);