perf tests: Add LLVM test for eBPF on-the-fly compiling
Previous patches introduce llvm__compile_bpf() to compile source file to
eBPF object. This patch adds testcase to test it. It also tests libbpf
by opening generated object after applying next patch which introduces
HAVE_LIBBPF_SUPPORT option.
Since llvm__compile_bpf() prints long messages which users who don't
explicitly test llvm doesn't care, this patch set verbose to -1 to
suppress all debug, warning and error message, and hint user use 'perf
test -v' to see the full output.
For the same reason, if clang is not found in PATH and there's no [llvm]
section in .perfconfig, skip this test.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/n/1436445342-1402-17-git-send-email-wangnan0@huawei.com
[ Add tools/lib/bpf/ to tools/perf/MANIFEST, so that the tarball targets build ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
new file mode 100644
index 0000000..a337356
--- /dev/null
+++ b/tools/perf/tests/llvm.c
@@ -0,0 +1,98 @@
+#include <stdio.h>
+#include <bpf/libbpf.h>
+#include <util/llvm-utils.h>
+#include <util/cache.h>
+#include "tests.h"
+#include "debug.h"
+
+static int perf_config_cb(const char *var, const char *val,
+ void *arg __maybe_unused)
+{
+ return perf_default_config(var, val, arg);
+}
+
+/*
+ * Randomly give it a "version" section since we don't really load it
+ * into kernel
+ */
+static const char test_bpf_prog[] =
+ "__attribute__((section(\"do_fork\"), used)) "
+ "int fork(void *ctx) {return 0;} "
+ "char _license[] __attribute__((section(\"license\"), used)) = \"GPL\";"
+ "int _version __attribute__((section(\"version\"), used)) = 0x40100;";
+
+#ifdef HAVE_LIBBPF_SUPPORT
+static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
+{
+ struct bpf_object *obj;
+
+ obj = bpf_object__open_buffer(obj_buf, obj_buf_sz);
+ if (!obj)
+ return -1;
+ bpf_object__close(obj);
+ return 0;
+}
+#else
+static int test__bpf_parsing(void *obj_buf __maybe_unused,
+ size_t obj_buf_sz __maybe_unused)
+{
+ fprintf(stderr, " (skip bpf parsing)");
+ return 0;
+}
+#endif
+
+int test__llvm(void)
+{
+ char *tmpl_new, *clang_opt_new;
+ void *obj_buf;
+ size_t obj_buf_sz;
+ int err, old_verbose;
+
+ perf_config(perf_config_cb, NULL);
+
+ /*
+ * Skip this test if user's .perfconfig doesn't set [llvm] section
+ * and clang is not found in $PATH, and this is not perf test -v
+ */
+ if (verbose == 0 && !llvm_param.user_set_param && llvm__search_clang()) {
+ fprintf(stderr, " (no clang, try 'perf test -v LLVM')");
+ return TEST_SKIP;
+ }
+
+ old_verbose = verbose;
+ /*
+ * llvm is verbosity when error. Suppress all error output if
+ * not 'perf test -v'.
+ */
+ if (verbose == 0)
+ verbose = -1;
+
+ if (!llvm_param.clang_bpf_cmd_template)
+ return -1;
+
+ if (!llvm_param.clang_opt)
+ llvm_param.clang_opt = strdup("");
+
+ err = asprintf(&tmpl_new, "echo '%s' | %s", test_bpf_prog,
+ llvm_param.clang_bpf_cmd_template);
+ if (err < 0)
+ return -1;
+ err = asprintf(&clang_opt_new, "-xc %s", llvm_param.clang_opt);
+ if (err < 0)
+ return -1;
+
+ llvm_param.clang_bpf_cmd_template = tmpl_new;
+ llvm_param.clang_opt = clang_opt_new;
+ err = llvm__compile_bpf("-", &obj_buf, &obj_buf_sz);
+
+ verbose = old_verbose;
+ if (err) {
+ if (!verbose)
+ fprintf(stderr, " (use -v to see error message)");
+ return -1;
+ }
+
+ err = test__bpf_parsing(obj_buf, obj_buf_sz);
+ free(obj_buf);
+ return err;
+}