diff mbox series

[4.9,034/171] perf report: Add warning when libunwind not compiled in

Message ID 20200102220551.746426321@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH Jan. 2, 2020, 10:06 p.m. UTC 
From: Jin Yao <yao.jin@linux.intel.com>

[ Upstream commit 800d3f561659b5436f8c57e7c26dd1f6928b5615 ]

We received a user report that call-graph DWARF mode was enabled in
'perf record' but 'perf report' didn't unwind the callstack correctly.
The reason was, libunwind was not compiled in.

We can use 'perf -vv' to check the compiled libraries but it would be
valuable to report a warning to user directly (especially valuable for
a perf newbie).

The warning is:

Warning:
Please install libunwind development packages during the perf build.

Both TUI and stdio are supported.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20191011022122.26369-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/perf/builtin-report.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff mbox series

Patch

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 6e88460cd13d..33ff5c843346 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -292,6 +292,13 @@  static int report__setup_sample_type(struct report *rep)
 				PERF_SAMPLE_BRANCH_ANY))
 		rep->nonany_branch_mode = true;
 
+#ifndef HAVE_LIBUNWIND_SUPPORT
+	if (dwarf_callchain_users) {
+		ui__warning("Please install libunwind development packages "
+			    "during the perf build.\n");
+	}
+#endif
+
 	return 0;
 }