[PATCH 14/53] perf test: Check environment before start real BPF test

From: Wang Nan
Date: Mon Jan 11 2016 - 09:03:53 EST


Copying perf to old kernel system results:

# perf test bpf
37: Test BPF filter :
37.1: Test basic BPF filtering : FAILED!
37.2: Test BPF prologue generation : Skip

However, in case when kernel doesn't support a test case it should
return 'Skip', 'FAILED!' should be reserved for kernel tests for when
the kernel supports a feature that then fails to work as advertised.

This patch checks environment before real testcase.

Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/tests/bpf.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)

diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index 33689a0..826b4b3 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -1,7 +1,11 @@
#include <stdio.h>
#include <sys/epoll.h>
+#include <util/util.h>
#include <util/bpf-loader.h>
#include <util/evlist.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <bpf/bpf.h>
#include "tests.h"
#include "llvm.h"
#include "debug.h"
@@ -227,6 +231,36 @@ const char *test__bpf_subtest_get_desc(int i)
return bpf_testcase_table[i].desc;
}

+static int check_env(void)
+{
+ int err;
+ unsigned int kver_int;
+ char license[] = "GPL";
+
+ struct bpf_insn insns[] = {
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ };
+
+ err = fetch_kernel_version(&kver_int, NULL, 0);
+ if (err) {
+ pr_debug("Unable to get kernel version\n");
+ return err;
+ }
+
+ err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
+ sizeof(insns) / sizeof(insns[0]),
+ license, kver_int, NULL, 0);
+ if (err < 0) {
+ pr_err("Missing basic BPF support, skip this test: %s\n",
+ strerror(errno));
+ return err;
+ }
+ close(err);
+
+ return 0;
+}
+
int test__bpf(int i)
{
int err;
@@ -239,6 +273,9 @@ int test__bpf(int i)
return TEST_SKIP;
}

+ if (check_env())
+ return TEST_SKIP;
+
err = __test__bpf(i);
return err;
}
--
1.8.3.4