[PATCH] perf test: Skip watchpoint tests if no watchpoints available

Naveen N. Rao
2022-11-21T10:28:44Z

On IBM Power9, perf watchpoint tests fail since no hardware breakpoints
are available. Detect this by checking the error returned by
perf_event_open() and skip the tests in that case.

Reported-by: Disha Goel <disgoel@linux.vnet.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
tools/perf/tests/wp.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/tools/perf/tests/wp.c b/tools/perf/tests/wp.c
index 56455da30341b4..cc8719609b19ea 100644
--- a/tools/perf/tests/wp.c
+++ b/tools/perf/tests/wp.c
@@ -59,8 +59,10 @@ static int __event(int wp_type, void *wp_addr, unsigned long wp_len)
get__perf_event_attr(&attr, wp_type, wp_addr, wp_len);
fd = sys_perf_event_open(&attr, 0, -1, -1,
perf_event_open_cloexec_flag());
- if (fd < 0)
+ if (fd < 0) {
+ fd = -errno;
pr_debug("failed opening event %x\n", attr.bp_type);
+ }

return fd;
}
@@ -77,7 +79,7 @@ static int test__wp_ro(struct test_suite *test __maybe_unused,

fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1));
if (fd < 0)
- return -1;
+ return fd == -ENODEV ? TEST_SKIP : -1;

tmp = data1;
WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
@@ -101,7 +103,7 @@ static int test__wp_wo(struct test_suite *test __maybe_unused,

fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
if (fd < 0)
- return -1;
+ return fd == -ENODEV ? TEST_SKIP : -1;

tmp = data1;
WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0);
@@ -126,7 +128,7 @@ static int test__wp_rw(struct test_suite *test __maybe_unused,
fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1,
sizeof(data1));
if (fd < 0)
- return -1;
+ return fd == -ENODEV ? TEST_SKIP : -1;

tmp = data1;
WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1);
@@ -150,7 +152,7 @@ static int test__wp_modify(struct test_suite *test __maybe_unused, int subtest _

fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
if (fd < 0)
- return -1;
+ return fd == -ENODEV ? TEST_SKIP : -1;

data1 = tmp;
WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);

base-commit: 63a3bf5e8d9e79ce456c8f73d4395a5a51d841b1
--
2.38.1