perf record: Add a fallback to the reference relocation symbol

Usually "_text" is enough, but I received reports that its not always
available, so fallback to "_stext" for the symbol we use to check if we
need to apply any relocation to all the symbols in the kernel symtab,
for when, for instance, kexec is being used.

Reported-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Darren Hart <dvhltc@us.ibm.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>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 60ecdd3dd26dd9457e4464c1138803482072d62a..80dc444031df97d066cb69820cf6e5d7a8ccbb54 100644 (file)
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -575,6 +575,9 @@ static int __cmd_record(int argc, const char **argv)
 
        err = event__synthesize_kernel_mmap(process_synthesized_event,
                                            session, "_text");
+       if (err < 0)
+               err = event__synthesize_kernel_mmap(process_synthesized_event,
+                                                   session, "_stext");
        if (err < 0) {
                pr_err("Couldn't record kernel reference relocation symbol.\n");
                return err;