From 9bc898c7019383b6aa2ae6cb2928c4ca926449f0 Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Wed, 8 Jul 2015 10:04:02 +0000 Subject: [PATCH] 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 Acked-by: Alexei Starovoitov Cc: Brendan Gregg Cc: Daniel Borkmann Cc: David Ahern Cc: He Kuang Cc: Jiri Olsa Cc: Kaixu Xia Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li 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 --- tools/perf/MANIFEST | 1 + tools/perf/tests/Build | 1 + tools/perf/tests/builtin-test.c | 4 ++ tools/perf/tests/llvm.c | 98 +++++++++++++++++++++++++++++++++ tools/perf/tests/tests.h | 1 + tools/perf/util/llvm-utils.c | 9 +++ tools/perf/util/llvm-utils.h | 10 ++++ 7 files changed, 124 insertions(+) create mode 100644 tools/perf/tests/llvm.c diff --git a/tools/perf/MANIFEST b/tools/perf/MANIFEST index d01a0aad5a01..f31f15a5f873 100644 --- a/tools/perf/MANIFEST +++ b/tools/perf/MANIFEST @@ -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 diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build index d20d6e6ab65b..c1518bdd0f1b 100644 --- a/tools/perf/tests/Build +++ b/tools/perf/tests/Build @@ -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 diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c index c1dde733c3a6..136cd934be66 100644 --- a/tools/perf/tests/builtin-test.c +++ b/tools/perf/tests/builtin-test.c @@ -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, }, diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c new file mode 100644 index 000000000000..a337356fd979 --- /dev/null +++ b/tools/perf/tests/llvm.c @@ -0,0 +1,98 @@ +#include +#include +#include +#include +#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; +} diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h index ebb47d96bc0b..bf113a247987 100644 --- a/tools/perf/tests/tests.h +++ b/tools/perf/tests/tests.h @@ -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 diff --git a/tools/perf/util/llvm-utils.c b/tools/perf/util/llvm-utils.c index 5887bb8c1243..4f6a4780bd5f 100644 --- a/tools/perf/util/llvm-utils.c +++ b/tools/perf/util/llvm-utils.c @@ -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 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf, *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); +} diff --git a/tools/perf/util/llvm-utils.h b/tools/perf/util/llvm-utils.h index d23adbca120b..5b3cf1c229e2 100644 --- a/tools/perf/util/llvm-utils.h +++ b/tools/perf/util/llvm-utils.h @@ -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