perf s390: Fix 'start' address of module's map
At present, when creating module's map, perf gets 'start' address by
parsing '/proc/modules', but it's the module base address, it isn't the
start address of the '.text' section.
In most arches, it's OK. But for s390, it places 'GOT' and 'PLT'
relocations before '.text' section. So there exists an offset between
module base address and '.text' section, which will incur wrong symbol
resolution for modules.
Fix this bug by getting 'start' address of module's map from parsing
'/sys/module/[module name]/sections/.text', not from '/proc/modules'.
Signed-off-by: Song Shan Gong <gongss@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1469070651-6447-2-git-send-email-gongss@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index bc2cdbd..cb6388d 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1093,12 +1093,20 @@
return map_groups__set_modules_path_dir(&machine->kmaps, modules_path, 0);
}
+int __weak arch__fix_module_text_start(u64 *start __maybe_unused,
+ const char *name __maybe_unused)
+{
+ return 0;
+}
static int machine__create_module(void *arg, const char *name, u64 start)
{
struct machine *machine = arg;
struct map *map;
+ if (arch__fix_module_text_start(&start, name) < 0)
+ return -1;
+
map = machine__findnew_module_map(machine, start, name);
if (map == NULL)
return -1;