perf session: Make read_build_id routines look at the host_machine too

The changes made to support host and guest machines in a session, that
started when the 'perf kvm' tool was introduced ended up introducing a
bug where the host_machine was not having its DSOs traversed for
build-id processing.

Fix it by moving some methods to the right classes and considering the
host_machine when processing build-ids.

Reported-by: Tom Zanussi <tzanussi@gmail.com>
Reported-by: Stephane Eranian <eranian@google.com>
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: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

5 files changed, 69 insertions, 40 deletions

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 8847bec64c54..1f62435f96c2 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -221,29 +221,38 @@ static int __dsos__write_buildid_table(struct list_head *head, pid_t pid,
         return 0;
 }
 
+static int machine__write_buildid_table(struct machine *self, int fd)
+{
+        int err;
+        u16 kmisc = PERF_RECORD_MISC_KERNEL,
+            umisc = PERF_RECORD_MISC_USER;
+
+        if (!machine__is_host(self)) {
+                kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
+                umisc = PERF_RECORD_MISC_GUEST_USER;
+        }
+
+        err = __dsos__write_buildid_table(&self->kernel_dsos, self->pid,
+                                          kmisc, fd);
+        if (err == 0)
+                err = __dsos__write_buildid_table(&self->user_dsos,
+                                                  self->pid, umisc, fd);
+        return err;
+}
+
 static int dsos__write_buildid_table(struct perf_header *header, int fd)
 {
         struct perf_session *session = container_of(header,
                         struct perf_session, header);
         struct rb_node *nd;
-        int err = 0;
-        u16 kmisc, umisc;
+        int err = machine__write_buildid_table(&session->host_machine, fd);
+
+        if (err)
+                return err;
 
         for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
-                if (machine__is_host(pos)) {
-                        kmisc = PERF_RECORD_MISC_KERNEL;
-                        umisc = PERF_RECORD_MISC_USER;
-                } else {
-                        kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
-                        umisc = PERF_RECORD_MISC_GUEST_USER;
-                }
-
-                err = __dsos__write_buildid_table(&pos->kernel_dsos, pos->pid,
-                                                  kmisc, fd);
-                if (err == 0)
-                        err = __dsos__write_buildid_table(&pos->user_dsos,
-                                                          pos->pid, umisc, fd);
+                err = machine__write_buildid_table(pos, fd);
                 if (err)
                         break;
         }
@@ -363,12 +372,17 @@ static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
         return err;
 }
 
-static int dsos__cache_build_ids(struct perf_header *self)
+static int machine__cache_build_ids(struct machine *self, const char *debugdir)
+{
+        int ret = __dsos__cache_build_ids(&self->kernel_dsos, debugdir);
+        ret |= __dsos__cache_build_ids(&self->user_dsos, debugdir);
+        return ret;
+}
+
+static int perf_session__cache_build_ids(struct perf_session *self)
 {
-        struct perf_session *session = container_of(self,
-                        struct perf_session, header);
         struct rb_node *nd;
-        int ret = 0;
+        int ret;
         char debugdir[PATH_MAX];
 
         snprintf(debugdir, sizeof(debugdir), "%s/%s", getenv("HOME"),
@@ -377,25 +391,30 @@ static int dsos__cache_build_ids(struct perf_header *self)
         if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
                 return -1;
 
-        for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
+        ret = machine__cache_build_ids(&self->host_machine, debugdir);
+
+        for (nd = rb_first(&self->machines); nd; nd = rb_next(nd)) {
                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
-                ret |= __dsos__cache_build_ids(&pos->kernel_dsos, debugdir);
-                ret |= __dsos__cache_build_ids(&pos->user_dsos, debugdir);
+                ret |= machine__cache_build_ids(pos, debugdir);
         }
         return ret ? -1 : 0;
 }
 
-static bool dsos__read_build_ids(struct perf_header *self, bool with_hits)
+static bool machine__read_build_ids(struct machine *self, bool with_hits)
+{
+        bool ret = __dsos__read_build_ids(&self->kernel_dsos, with_hits);
+        ret |= __dsos__read_build_ids(&self->user_dsos, with_hits);
+        return ret;
+}
+
+static bool perf_session__read_build_ids(struct perf_session *self, bool with_hits)
 {
-        bool ret = false;
-        struct perf_session *session = container_of(self,
-                        struct perf_session, header);
         struct rb_node *nd;
+        bool ret = machine__read_build_ids(&self->host_machine, with_hits);
 
-        for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
+        for (nd = rb_first(&self->machines); nd; nd = rb_next(nd)) {
                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
-                ret |= __dsos__read_build_ids(&pos->kernel_dsos, with_hits);
-                ret |= __dsos__read_build_ids(&pos->user_dsos, with_hits);
+                ret |= machine__read_build_ids(pos, with_hits);
         }
 
         return ret;
@@ -404,12 +423,14 @@ static bool dsos__read_build_ids(struct perf_header *self, bool with_hits)
 static int perf_header__adds_write(struct perf_header *self, int fd)
 {
         int nr_sections;
+        struct perf_session *session;
         struct perf_file_section *feat_sec;
         int sec_size;
         u64 sec_start;
         int idx = 0, err;
 
-        if (dsos__read_build_ids(self, true))
+        session = container_of(self, struct perf_session, header);
+        if (perf_session__read_build_ids(session, true))
                 perf_header__set_feat(self, HEADER_BUILD_ID);
 
         nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
@@ -450,7 +471,7 @@ static int perf_header__adds_write(struct perf_header *self, int fd)
                 }
                 buildid_sec->size = lseek(fd, 0, SEEK_CUR) -
                                           buildid_sec->offset;
-                dsos__cache_build_ids(self);
+                perf_session__cache_build_ids(session);
         }
 
         lseek(fd, sec_start, SEEK_SET);
@@ -490,7 +511,6 @@ int perf_header__write(struct perf_header *self, int fd, bool at_exit)
 
         lseek(fd, sizeof(f_header), SEEK_SET);
 
-
         for (i = 0; i < self->attrs; i++) {
                 attr = self->attr[i];
 
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index e4eaa6d02f57..8f83a1835766 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -895,3 +895,10 @@ size_t perf_session__fprintf_dsos(struct perf_session *self, FILE *fp)
                __dsos__fprintf(&self->host_machine.user_dsos, fp) +
                machines__fprintf_dsos(&self->machines, fp);