[PATCH 24/24] perf tests: Add LLVM test for eBPF on-the-fly compiling
From: Arnaldo Carvalho de Melo
Date: Fri Aug 07 2015 - 10:51:42 EST
From: Wang Nan <wangnan0@xxxxxxxxxx>
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@xxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kaixu Xia <xiakaixu@xxxxxxxxxx>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: pi3orama@xxxxxxx
Link: http://lkml.kernel.org/n/1436445342-1402-17-git-send-email-wangnan0@xxxxxxxxxx
[ Add tools/lib/bpf/ to tools/perf/MANIFEST, so that the tarball targets build ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
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
@@ -175,6 +175,10 @@ static struct test {
.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 <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;
+}
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 @@ 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);
+}
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
--
2.1.0
--
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