linux/tools/perf/tests/llvm.c
Wang Nan 9bc898c701 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>
2015-08-07 10:57:24 -03:00

99 lines
2.3 KiB
C

#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;
}