perf symbols: Use only --vmlinux if specified
Found while analysing a perf.data file collected on an ARM
machine where an explicitely specified vmlinux was being
disregarded.
Reported-by: Jamie Iles <jamie.iles@picochip.com>
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: <1263904574-30732-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index a4e7459..b6ab23d 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1572,7 +1572,7 @@
return -1;
dso__set_loaded(self, map->type);
- err = dso__load_sym(self, map, session, self->long_name, fd, filter, 1, 0);
+ err = dso__load_sym(self, map, session, vmlinux, fd, filter, 1, 0);
close(fd);
return err;
@@ -1584,6 +1584,26 @@
int err;
const char *kallsyms_filename = NULL;
char *kallsyms_allocated_filename = NULL;
+ /*
+ * Step 1: if the user specified a vmlinux filename, use it and only
+ * it, reporting errors to the user if it cannot be used.
+ *
+ * For instance, try to analyse an ARM perf.data file _without_ a
+ * build-id, or if the user specifies the wrong path to the right
+ * vmlinux file, obviously we can't fallback to another vmlinux (a
+ * x86_86 one, on the machine where analysis is being performed, say),
+ * or worse, /proc/kallsyms.
+ *
+ * If the specified file _has_ a build-id and there is a build-id
+ * section in the perf.data file, we will still do the expected
+ * validation in dso__load_vmlinux and will bail out if they don't
+ * match.
+ */
+ if (symbol_conf.vmlinux_name != NULL) {
+ err = dso__load_vmlinux(self, map, session,
+ symbol_conf.vmlinux_name, filter);
+ goto out_try_fixup;
+ }
if (vmlinux_path != NULL) {
int i;
@@ -1618,46 +1638,41 @@
goto do_kallsyms;
}
}
-
+ /*
+ * Now look if we have it on the build-id cache in
+ * $HOME/.debug/[kernel.kallsyms].
+ */
build_id__sprintf(self->build_id, sizeof(self->build_id),
sbuild_id);
if (asprintf(&kallsyms_allocated_filename,
"%s/.debug/[kernel.kallsyms]/%s",
- getenv("HOME"), sbuild_id) != -1) {
- if (access(kallsyms_filename, F_OK)) {
- kallsyms_filename = kallsyms_allocated_filename;
- goto do_kallsyms;
- }
- free(kallsyms_allocated_filename);
- kallsyms_allocated_filename = NULL;
- }
-
- goto do_vmlinux;
- }
-
- if (self->long_name[0] == '[') {
- kallsyms_filename = "/proc/kallsyms";
- goto do_kallsyms;
- }
-
-do_vmlinux:
- err = dso__load_vmlinux(self, map, session, self->long_name, filter);
- if (err <= 0) {
- if (self->has_build_id)
+ getenv("HOME"), sbuild_id) == -1)
return -1;
- pr_info("The file %s cannot be used, "
- "trying to use /proc/kallsyms...", self->long_name);
-do_kallsyms:
- err = dso__load_kallsyms(self, kallsyms_filename, map, session, filter);
- if (err > 0 && kallsyms_filename == NULL)
- dso__set_long_name(self, strdup("[kernel.kallsyms]"));
- free(kallsyms_allocated_filename);
+ if (access(kallsyms_filename, F_OK)) {
+ free(kallsyms_allocated_filename);
+ return -1;
+ }
+
+ kallsyms_filename = kallsyms_allocated_filename;
+ } else {
+ /*
+ * Last resort, if we don't have a build-id and couldn't find
+ * any vmlinux file, try the running kernel kallsyms table.
+ */
+ kallsyms_filename = "/proc/kallsyms";
}
+do_kallsyms:
+ err = dso__load_kallsyms(self, kallsyms_filename, map, session, filter);
+ free(kallsyms_allocated_filename);
+
+out_try_fixup:
if (err > 0) {
out_fixup:
+ if (kallsyms_filename == NULL)
+ dso__set_long_name(self, strdup("[kernel.kallsyms]"));
map__fixup_start(map);
map__fixup_end(map);
}