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>
This commit is contained in:
Wang Nan 2015-07-08 10:04:02 +00:00 committed by Arnaldo Carvalho de Melo
parent 0c6d18bfd5
commit 9bc898c701
7 changed files with 124 additions and 0 deletions

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@ -18,6 +18,7 @@ tools/arch/x86/include/asm/atomic.h
tools/arch/x86/include/asm/rmwcc.h
tools/lib/traceevent
tools/lib/api
tools/lib/bpf
tools/lib/hweight.c
tools/lib/rbtree.c
tools/lib/symbol/kallsyms.c

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@ -32,6 +32,7 @@ perf-y += sample-parsing.o
perf-y += parse-no-sample-id-all.o
perf-y += kmod-path.o
perf-y += thread-map.o
perf-y += llvm.o
perf-$(CONFIG_X86) += perf-time-to-tsc.o

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@ -174,6 +174,10 @@ static struct test {
.desc = "Test thread map",
.func = test__thread_map,
},
{
.desc = "Test LLVM searching and compiling",
.func = test__llvm,
},
{
.func = NULL,
},

98
tools/perf/tests/llvm.c Normal file
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@ -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;
}

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@ -62,6 +62,7 @@ int test__fdarray__filter(void);
int test__fdarray__add(void);
int test__kmod_path__parse(void);
int test__thread_map(void);
int test__llvm(void);
#if defined(__x86_64__) || defined(__i386__) || defined(__arm__) || defined(__aarch64__)
#ifdef HAVE_DWARF_UNWIND_SUPPORT

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@ -22,6 +22,7 @@ struct llvm_param llvm_param = {
.clang_opt = NULL,
.kbuild_dir = NULL,
.kbuild_opts = NULL,
.user_set_param = false,
};
int perf_llvm_config(const char *var, const char *value)
@ -42,6 +43,7 @@ int perf_llvm_config(const char *var, const char *value)
llvm_param.kbuild_opts = strdup(value);
else
return -1;
llvm_param.user_set_param = true;
return 0;
}
@ -397,3 +399,10 @@ errout:
*p_obj_buf_sz = 0;
return err;
}
int llvm__search_clang(void)
{
char clang_path[PATH_MAX];
return search_program(llvm_param.clang_path, "clang", clang_path);
}

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@ -29,6 +29,13 @@ struct llvm_param {
* compiling. Should not be used for dynamic compiling.
*/
const char *kbuild_opts;
/*
* Default is false. If one of the above fields is set by user
* explicitly then user_set_llvm is set to true. This is used
* for perf test. If user doesn't set anything in .perfconfig
* and clang is not found, don't trigger llvm test.
*/
bool user_set_param;
};
extern struct llvm_param llvm_param;
@ -36,4 +43,7 @@ extern int perf_llvm_config(const char *var, const char *value);
extern int llvm__compile_bpf(const char *path, void **p_obj_buf,
size_t *p_obj_buf_sz);
/* This function is for test__llvm() use only */
extern int llvm__search_clang(void);
#endif