summaryrefslogtreecommitdiff
path: root/tools/perf
diff options
context:
space:
mode:
authorWang Nan <wangnan0@huawei.com>2016-04-07 10:24:30 +0000
committerArnaldo Carvalho de Melo <acme@redhat.com>2016-04-08 09:58:14 -0300
commita58f7033ba892b7d299954b94471450d72623039 (patch)
treed04a4d8230b6231447ad736465429be145b2e489 /tools/perf
parent1b700c9975008615ad470cf79acc8455ce60a695 (diff)
perf symbols: Record text offset in dso to calculate objdump address
In this patch, the offset of '.text' section is stored into dso and used here to re-calculate address to objdump. In most of the cases, executable code is in '.text' section, so the adjustment made to a symbol in dso__load_sym (using sym.st_value -= shdr.sh_addr - shdr.sh_offset) should equal to 'sym.st_value -= dso->text_offset'. Therefore, adding text_offset back get objdump address from symbol address (rip). However, it is not true for kernel and kernel module since there could be multiple executable sections with different offset. Exclude kernel for this reason. After this patch, even dso->adjust_symbols is set to true for shared objects, map__rip_2objdump() and map__objdump_2mem() would return correct result, so perf behavior of annotate won't be changed. Signed-off-by: Wang Nan <wangnan0@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Cody P Schafer <dev@codyps.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kirill Smelkov <kirr@nexedi.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1460024671-64774-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
-rw-r--r--tools/perf/util/map.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index 171b6d10a04b..02c31865648b 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -431,6 +431,13 @@ u64 map__rip_2objdump(struct map *map, u64 rip)
if (map->dso->rel)
return rip - map->pgoff;
+ /*
+ * kernel modules also have DSO_TYPE_USER in dso->kernel,
+ * but all kernel modules are ET_REL, so won't get here.
+ */
+ if (map->dso->kernel == DSO_TYPE_USER)
+ return rip + map->dso->text_offset;
+
return map->unmap_ip(map, rip) - map->reloc;
}
@@ -454,6 +461,13 @@ u64 map__objdump_2mem(struct map *map, u64 ip)
if (map->dso->rel)
return map->unmap_ip(map, ip + map->pgoff);
+ /*
+ * kernel modules also have DSO_TYPE_USER in dso->kernel,
+ * but all kernel modules are ET_REL, so won't get here.
+ */
+ if (map->dso->kernel == DSO_TYPE_USER)
+ return map->unmap_ip(map, ip - map->dso->text_offset);
+
return ip + map->reloc;
}