selftests/bpf: Add a fexit/bpf2bpf test with target bpf prog no callees

The existing fexit_bpf2bpf test covers the target progrm with callees.
This patch added a test for the target program without callees.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191205010607.177904-1-yhs@fb.com

diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c
index 15c7378..b426bf2 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c
+++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c
@@ -2,25 +2,21 @@
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
 
-#define PROG_CNT 3
-
-void test_fexit_bpf2bpf(void)
+static void test_fexit_bpf2bpf_common(const char *obj_file,
+                                     const char *target_obj_file,
+                                     int prog_cnt,
+                                     const char **prog_name)
 {
-       const char *prog_name[PROG_CNT] = {
-               "fexit/test_pkt_access",
-               "fexit/test_pkt_access_subprog1",
-               "fexit/test_pkt_access_subprog2",
-       };
        struct bpf_object *obj = NULL, *pkt_obj;
        int err, pkt_fd, i;
-       struct bpf_link *link[PROG_CNT] = {};
-       struct bpf_program *prog[PROG_CNT];
+       struct bpf_link **link = NULL;
+       struct bpf_program **prog = NULL;
        __u32 duration, retval;
        struct bpf_map *data_map;
        const int zero = 0;
-       u64 result[PROG_CNT];
+       u64 *result = NULL;
 
-       err = bpf_prog_load("./test_pkt_access.o", BPF_PROG_TYPE_UNSPEC,
+       err = bpf_prog_load(target_obj_file, BPF_PROG_TYPE_UNSPEC,
                            &pkt_obj, &pkt_fd);
        if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
                return;
@@ -28,7 +24,14 @@ void test_fexit_bpf2bpf(void)
                            .attach_prog_fd = pkt_fd,
                           );
 
-       obj = bpf_object__open_file("./fexit_bpf2bpf.o", &opts);
+       link = calloc(sizeof(struct bpf_link *), prog_cnt);
+       prog = calloc(sizeof(struct bpf_program *), prog_cnt);
+       result = malloc(prog_cnt * sizeof(u64));
+       if (CHECK(!link || !prog || !result, "alloc_memory",
+                 "failed to alloc memory"))
+               goto close_prog;
+
+       obj = bpf_object__open_file(obj_file, &opts);
        if (CHECK(IS_ERR_OR_NULL(obj), "obj_open",
                  "failed to open fexit_bpf2bpf: %ld\n",
                  PTR_ERR(obj)))
@@ -38,7 +41,7 @@ void test_fexit_bpf2bpf(void)
        if (CHECK(err, "obj_load", "err %d\n", err))
                goto close_prog;
 
-       for (i = 0; i < PROG_CNT; i++) {
+       for (i = 0; i < prog_cnt; i++) {
                prog[i] = bpf_object__find_program_by_title(obj, prog_name[i]);
                if (CHECK(!prog[i], "find_prog", "prog %s not found\n", prog_name[i]))
                        goto close_prog;
@@ -56,21 +59,54 @@ void test_fexit_bpf2bpf(void)
              "err %d errno %d retval %d duration %d\n",
              err, errno, retval, duration);
 
-       err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, &result);
+       err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, result);
        if (CHECK(err, "get_result",
                  "failed to get output data: %d\n", err))
                goto close_prog;
 
-       for (i = 0; i < PROG_CNT; i++)
+       for (i = 0; i < prog_cnt; i++)
                if (CHECK(result[i] != 1, "result", "fexit_bpf2bpf failed err %ld\n",
                          result[i]))
                        goto close_prog;
 
 close_prog:
-       for (i = 0; i < PROG_CNT; i++)
+       for (i = 0; i < prog_cnt; i++)
                if (!IS_ERR_OR_NULL(link[i]))
                        bpf_link__destroy(link[i]);
        if (!IS_ERR_OR_NULL(obj))
                bpf_object__close(obj);
        bpf_object__close(pkt_obj);
+       free(link);
+       free(prog);
+       free(result);
+}
+
+static void test_target_no_callees(void)
+{
+       const char *prog_name[] = {
+               "fexit/test_pkt_md_access",
+       };
+       test_fexit_bpf2bpf_common("./fexit_bpf2bpf_simple.o",
+                                 "./test_pkt_md_access.o",
+                                 ARRAY_SIZE(prog_name),
+                                 prog_name);
+}
+
+static void test_target_yes_callees(void)
+{
+       const char *prog_name[] = {
+               "fexit/test_pkt_access",
+               "fexit/test_pkt_access_subprog1",
+               "fexit/test_pkt_access_subprog2",
+       };
+       test_fexit_bpf2bpf_common("./fexit_bpf2bpf.o",
+                                 "./test_pkt_access.o",
+                                 ARRAY_SIZE(prog_name),
+                                 prog_name);
+}
+
+void test_fexit_bpf2bpf(void)
+{
+       test_target_no_callees();
+       test_target_yes_callees();
 }

diff --git a/tools/testing/selftests/bpf/progs/fexit_bpf2bpf_simple.c b/tools/testing/selftests/bpf/progs/fexit_bpf2bpf_simple.c
new file mode 100644 (file)
index 0000000..ebc0ab7
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/fexit_bpf2bpf_simple.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Facebook */
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+#include "bpf_trace_helpers.h"
+
+struct sk_buff {
+       unsigned int len;
+};
+
+__u64 test_result = 0;
+BPF_TRACE_2("fexit/test_pkt_md_access", test_main2,
+           struct sk_buff *, skb, int, ret)
+{
+       int len;
+
+       __builtin_preserve_access_index(({
+               len = skb->len;
+       }));
+       if (len != 74 || ret != 0)
+               return 0;
+
+       test_result = 1;
+       return 0;
+}
+char _license[] SEC("license") = "GPL";

diff --git a/tools/testing/selftests/bpf/progs/test_pkt_md_access.c b/tools/testing/selftests/bpf/progs/test_pkt_md_access.c
index 3d039e1..1db2623 100644 (file)
--- a/tools/testing/selftests/bpf/progs/test_pkt_md_access.c
+++ b/tools/testing/selftests/bpf/progs/test_pkt_md_access.c
@@ -27,8 +27,8 @@ int _version SEC("version") = 1;
        }
 #endif
 
-SEC("test1")
-int process(struct __sk_buff *skb)
+SEC("classifier/test_pkt_md_access")
+int test_pkt_md_access(struct __sk_buff *skb)
 {
        TEST_FIELD(__u8,  len, 0xFF);
        TEST_FIELD(__u16, len, 0xFFFF);