[PATCH 4.19 129/219] perf probe: Fix to show inlined function callsite without entry_pc

Greg Kroah-Hartman
2019-12-29T17:33:13Z

From: Masami Hiramatsu <mhiramat@kernel.org>

[ Upstream commit 18e21eb671dc87a4f0546ba505a89ea93598a634 ]

Fix 'perf probe --line' option to show inlined function callsite lines
even if the function DIE has only ranges.

Without this:

# perf probe -L amd_put_event_constraints
...
2 {
3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
__amd_put_nb_event_constraints(cpuc, event);
5 }

With this patch:

# perf probe -L amd_put_event_constraints
...
2 {
3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
4 __amd_put_nb_event_constraints(cpuc, event);
5 }

Committer testing:

Before:

[root@quaco ~]# perf probe -L amd_put_event_constraints
<amd_put_event_constraints@/usr/src/debug/kernel-5.2.fc30/linux-5.2.18-200.fc30.x86_64/arch/x86/events/amd/core.c:0>
0 static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
2 {
3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
__amd_put_nb_event_constraints(cpuc, event);
5 }

PMU_FORMAT_ATTR(event, "config:0-7,32-35");
PMU_FORMAT_ATTR(umask, "config:8-15" );

[root@quaco ~]#

After:

[root@quaco ~]# perf probe -L amd_put_event_constraints
<amd_put_event_constraints@/usr/src/debug/kernel-5.2.fc30/linux-5.2.18-200.fc30.x86_64/arch/x86/events/amd/core.c:0>
0 static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
2 {
3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
4 __amd_put_nb_event_constraints(cpuc, event);
5 }

PMU_FORMAT_ATTR(event, "config:0-7,32-35");
PMU_FORMAT_ATTR(umask, "config:8-15" );

[root@quaco ~]# perf probe amd_put_event_constraints:4
Added new event:
probe:amd_put_event_constraints (on amd_put_event_constraints:4)

You can now use it in all perf tools, such as:

perf record -e probe:amd_put_event_constraints -aR sleep 1

[root@quaco ~]#

[root@quaco ~]# perf probe -l
probe:amd_put_event_constraints (on amd_put_event_constraints:4@arch/x86/events/amd/core.c)
probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask@kernel/cpu.c)
[root@quaco ~]#

Using it:

[root@quaco ~]# perf trace -e probe:*
^C[root@quaco ~]#

Ok, Intel system here... :-)

Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/157199322107.8075.12659099000567865708.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/perf/util/dwarf-aux.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index 14a3da24a0a8..fc3f3573332d 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -686,7 +686,7 @@ static int __die_walk_funclines_cb(Dwarf_Die *in_die, void *data)
if (dwarf_tag(in_die) == DW_TAG_inlined_subroutine) {
fname = die_get_call_file(in_die);
lineno = die_get_call_lineno(in_die);
- if (fname && lineno > 0 && dwarf_entrypc(in_die, &addr) == 0) {
+ if (fname && lineno > 0 && die_entrypc(in_die, &addr) == 0) {
lw->retval = lw->callback(fname, lineno, addr, lw->data);
if (lw->retval != 0)
return DIE_FIND_CB_END;
--
2.20.1