[PATCH] perf report: Fix no libunwind compiled warning break s390 issue

From: Jin Yao
Date: Tue Jan 07 2020 - 21:43:52 EST


Commit 800d3f561659 ("perf report: Add warning when libunwind not compiled in")
breaks the s390 platform. S390 uses libdw-dwarf-unwind for call chain
unwinding and had no support for libunwind.

So the warning "Please install libunwind development packages during the perf build."
caused the confusion even if the call-graph is displayed correctly.

This patch adds checking for HAVE_DWARF_SUPPORT, which is set when
libdw-dwarf-unwind is compiled in.

Fixes: 800d3f561659 ("perf report: Add warning when libunwind not compiled in")

Reviewed-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Tested-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
tools/perf/builtin-report.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index de988589d99b..66cd97cc8b92 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -412,10 +412,10 @@ static int report__setup_sample_type(struct report *rep)
PERF_SAMPLE_BRANCH_ANY))
rep->nonany_branch_mode = true;

-#ifndef HAVE_LIBUNWIND_SUPPORT
+#if !defined(HAVE_LIBUNWIND_SUPPORT) && !defined(HAVE_DWARF_SUPPORT)
if (dwarf_callchain_users) {
- ui__warning("Please install libunwind development packages "
- "during the perf build.\n");
+ ui__warning("Please install libunwind or libdw "
+ "development packages during the perf build.\n");
}
#endif

--
2.17.1