From: Daniel Borkmann <daniel@iogearbox.net>
To: ast@kernel.org
Cc: john.fastabend@gmail.com, andrii.nakryiko@gmail.com,
netdev@vger.kernel.org, bpf@vger.kernel.org,
Daniel Borkmann <daniel@iogearbox.net>
Subject: [PATCH bpf-next v2 8/8] bpf, testing: add various tail call test cases
Date: Fri, 22 Nov 2019 21:08:01 +0100 [thread overview]
Message-ID: <3d6cbecbeb171117dccfe153306e479798fb608d.1574452833.git.daniel@iogearbox.net> (raw)
In-Reply-To: <cover.1574452833.git.daniel@iogearbox.net>
Add several BPF kselftest cases for tail calls which test the various
patch directions, and that multiple locations are patched in same and
different programs.
# ./test_progs -n 45
#45/1 tailcall_1:OK
#45/2 tailcall_2:OK
#45/3 tailcall_3:OK
#45/4 tailcall_4:OK
#45/5 tailcall_5:OK
#45 tailcalls:OK
Summary: 1/5 PASSED, 0 SKIPPED, 0 FAILED
I've also verified the JITed dump after each of the rewrite cases that
it matches expectations.
Also regular test_verifier suite passes fine which contains further tail
call tests:
# ./test_verifier
[...]
Summary: 1563 PASSED, 0 SKIPPED, 0 FAILED
Checked under JIT, interpreter and JIT + hardening.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
.../selftests/bpf/prog_tests/tailcalls.c | 487 ++++++++++++++++++
tools/testing/selftests/bpf/progs/tailcall1.c | 48 ++
tools/testing/selftests/bpf/progs/tailcall2.c | 59 +++
tools/testing/selftests/bpf/progs/tailcall3.c | 31 ++
tools/testing/selftests/bpf/progs/tailcall4.c | 33 ++
tools/testing/selftests/bpf/progs/tailcall5.c | 40 ++
6 files changed, 698 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/tailcalls.c
create mode 100644 tools/testing/selftests/bpf/progs/tailcall1.c
create mode 100644 tools/testing/selftests/bpf/progs/tailcall2.c
create mode 100644 tools/testing/selftests/bpf/progs/tailcall3.c
create mode 100644 tools/testing/selftests/bpf/progs/tailcall4.c
create mode 100644 tools/testing/selftests/bpf/progs/tailcall5.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c
new file mode 100644
index 000000000000..bb8fe646dd9f
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c
@@ -0,0 +1,487 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+
+/* test_tailcall_1 checks basic functionality by patching multiple locations
+ * in a single program for a single tail call slot with nop->jmp, jmp->nop
+ * and jmp->jmp rewrites. Also checks for nop->nop.
+ */
+static void test_tailcall_1(void)
+{
+ int err, map_fd, prog_fd, main_fd, i, j;
+ struct bpf_map *prog_array;
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ __u32 retval, duration;
+ char prog_name[32];
+ char buff[128] = {};
+
+ err = bpf_prog_load("tailcall1.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
+ &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ prog = bpf_object__find_program_by_title(obj, "classifier");
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ main_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(main_fd < 0))
+ goto out;
+
+ prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
+ if (CHECK_FAIL(!prog_array))
+ goto out;
+
+ map_fd = bpf_map__fd(prog_array);
+ if (CHECK_FAIL(map_fd < 0))
+ goto out;
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ snprintf(prog_name, sizeof(prog_name), "classifier/%i", i);
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != i, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 3, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ snprintf(prog_name, sizeof(prog_name), "classifier/%i", i);
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 0, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ j = bpf_map__def(prog_array)->max_entries - 1 - i;
+ snprintf(prog_name, sizeof(prog_name), "classifier/%i", j);
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ j = bpf_map__def(prog_array)->max_entries - 1 - i;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != j, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 3, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err >= 0 || errno != ENOENT))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 3, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+ }
+
+out:
+ bpf_object__close(obj);
+}
+
+/* test_tailcall_2 checks that patching multiple programs for a single
+ * tail call slot works. It also jumps through several programs and tests
+ * the tail call limit counter.
+ */
+static void test_tailcall_2(void)
+{
+ int err, map_fd, prog_fd, main_fd, i;
+ struct bpf_map *prog_array;
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ __u32 retval, duration;
+ char prog_name[32];
+ char buff[128] = {};
+
+ err = bpf_prog_load("tailcall2.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
+ &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ prog = bpf_object__find_program_by_title(obj, "classifier");
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ main_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(main_fd < 0))
+ goto out;
+
+ prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
+ if (CHECK_FAIL(!prog_array))
+ goto out;
+
+ map_fd = bpf_map__fd(prog_array);
+ if (CHECK_FAIL(map_fd < 0))
+ goto out;
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ snprintf(prog_name, sizeof(prog_name), "classifier/%i", i);
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 2, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+
+ i = 2;
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 1, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+
+ i = 0;
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 3, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+out:
+ bpf_object__close(obj);
+}
+
+/* test_tailcall_3 checks that the count value of the tail call limit
+ * enforcement matches with expectations.
+ */
+static void test_tailcall_3(void)
+{
+ int err, map_fd, prog_fd, main_fd, data_fd, i, val;
+ struct bpf_map *prog_array, *data_map;
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ __u32 retval, duration;
+ char buff[128] = {};
+
+ err = bpf_prog_load("tailcall3.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
+ &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ prog = bpf_object__find_program_by_title(obj, "classifier");
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ main_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(main_fd < 0))
+ goto out;
+
+ prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
+ if (CHECK_FAIL(!prog_array))
+ goto out;
+
+ map_fd = bpf_map__fd(prog_array);
+ if (CHECK_FAIL(map_fd < 0))
+ goto out;
+
+ prog = bpf_object__find_program_by_title(obj, "classifier/0");
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ i = 0;
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 1, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+
+ data_map = bpf_object__find_map_by_name(obj, "tailcall.bss");
+ if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map)))
+ return;
+
+ data_fd = bpf_map__fd(data_map);
+ if (CHECK_FAIL(map_fd < 0))
+ return;
+
+ i = 0;
+ err = bpf_map_lookup_elem(data_fd, &i, &val);
+ CHECK(err || val != 33, "tailcall count", "err %d errno %d count %d\n",
+ err, errno, val);
+
+ i = 0;
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 0, "tailcall", "err %d errno %d retval %d\n",
+ err, errno, retval);
+out:
+ bpf_object__close(obj);
+}
+
+/* test_tailcall_4 checks that the kernel properly selects indirect jump
+ * for the case where the key is not known. Latter is passed via global
+ * data to select different targets we can compare return value of.
+ */
+static void test_tailcall_4(void)
+{
+ int err, map_fd, prog_fd, main_fd, data_fd, i;
+ struct bpf_map *prog_array, *data_map;
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ __u32 retval, duration;
+ static const int zero = 0;
+ char buff[128] = {};
+ char prog_name[32];
+
+ err = bpf_prog_load("tailcall4.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
+ &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ prog = bpf_object__find_program_by_title(obj, "classifier");
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ main_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(main_fd < 0))
+ goto out;
+
+ prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
+ if (CHECK_FAIL(!prog_array))
+ goto out;
+
+ map_fd = bpf_map__fd(prog_array);
+ if (CHECK_FAIL(map_fd < 0))
+ goto out;
+
+ data_map = bpf_object__find_map_by_name(obj, "tailcall.bss");
+ if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map)))
+ return;
+
+ data_fd = bpf_map__fd(data_map);
+ if (CHECK_FAIL(map_fd < 0))
+ return;
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ snprintf(prog_name, sizeof(prog_name), "classifier/%i", i);
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ err = bpf_map_update_elem(data_fd, &zero, &i, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != i, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+ }
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ err = bpf_map_update_elem(data_fd, &zero, &i, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 3, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+ }
+out:
+ bpf_object__close(obj);
+}
+
+/* test_tailcall_5 probes similarly to test_tailcall_4 that the kernel generates
+ * an indirect jump when the keys are const but different from different branches.
+ */
+static void test_tailcall_5(void)
+{
+ int err, map_fd, prog_fd, main_fd, data_fd, i, key[] = { 1111, 1234, 5678 };
+ struct bpf_map *prog_array, *data_map;
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ __u32 retval, duration;
+ static const int zero = 0;
+ char buff[128] = {};
+ char prog_name[32];
+
+ err = bpf_prog_load("tailcall5.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
+ &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ prog = bpf_object__find_program_by_title(obj, "classifier");
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ main_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(main_fd < 0))
+ goto out;
+
+ prog_array = bpf_object__find_map_by_name(obj, "jmp_table");
+ if (CHECK_FAIL(!prog_array))
+ goto out;
+
+ map_fd = bpf_map__fd(prog_array);
+ if (CHECK_FAIL(map_fd < 0))
+ goto out;
+
+ data_map = bpf_object__find_map_by_name(obj, "tailcall.bss");
+ if (CHECK_FAIL(!data_map || !bpf_map__is_internal(data_map)))
+ return;
+
+ data_fd = bpf_map__fd(data_map);
+ if (CHECK_FAIL(map_fd < 0))
+ return;
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ snprintf(prog_name, sizeof(prog_name), "classifier/%i", i);
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK_FAIL(!prog))
+ goto out;
+
+ prog_fd = bpf_program__fd(prog);
+ if (CHECK_FAIL(prog_fd < 0))
+ goto out;
+
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+ }
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ err = bpf_map_update_elem(data_fd, &zero, &key[i], BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != i, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+ }
+
+ for (i = 0; i < bpf_map__def(prog_array)->max_entries; i++) {
+ err = bpf_map_update_elem(data_fd, &zero, &key[i], BPF_ANY);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ err = bpf_prog_test_run(main_fd, 1, buff, sizeof(buff), 0,
+ &duration, &retval, NULL);
+ CHECK(err || retval != 3, "tailcall",
+ "err %d errno %d retval %d\n", err, errno, retval);
+ }
+out:
+ bpf_object__close(obj);
+}
+
+void test_tailcalls(void)
+{
+ if (test__start_subtest("tailcall_1"))
+ test_tailcall_1();
+ if (test__start_subtest("tailcall_2"))
+ test_tailcall_2();
+ if (test__start_subtest("tailcall_3"))
+ test_tailcall_3();
+ if (test__start_subtest("tailcall_4"))
+ test_tailcall_4();
+ if (test__start_subtest("tailcall_5"))
+ test_tailcall_5();
+}
diff --git a/tools/testing/selftests/bpf/progs/tailcall1.c b/tools/testing/selftests/bpf/progs/tailcall1.c
new file mode 100644
index 000000000000..63531e1a9fa4
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall1.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+
+#include "bpf_helpers.h"
+
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 3);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+#define TAIL_FUNC(x) \
+ SEC("classifier/" #x) \
+ int bpf_func_##x(struct __sk_buff *skb) \
+ { \
+ return x; \
+ }
+TAIL_FUNC(0)
+TAIL_FUNC(1)
+TAIL_FUNC(2)
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+ /* Multiple locations to make sure we patch
+ * all of them.
+ */
+ bpf_tail_call(skb, &jmp_table, 0);
+ bpf_tail_call(skb, &jmp_table, 0);
+ bpf_tail_call(skb, &jmp_table, 0);
+ bpf_tail_call(skb, &jmp_table, 0);
+
+ bpf_tail_call(skb, &jmp_table, 1);
+ bpf_tail_call(skb, &jmp_table, 1);
+ bpf_tail_call(skb, &jmp_table, 1);
+ bpf_tail_call(skb, &jmp_table, 1);
+
+ bpf_tail_call(skb, &jmp_table, 2);
+ bpf_tail_call(skb, &jmp_table, 2);
+ bpf_tail_call(skb, &jmp_table, 2);
+ bpf_tail_call(skb, &jmp_table, 2);
+
+ return 3;
+}
+
+char __license[] SEC("license") = "GPL";
+int _version SEC("version") = 1;
diff --git a/tools/testing/selftests/bpf/progs/tailcall2.c b/tools/testing/selftests/bpf/progs/tailcall2.c
new file mode 100644
index 000000000000..21c85c477210
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall2.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+
+#include "bpf_helpers.h"
+
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 5);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+SEC("classifier/0")
+int bpf_func_0(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, 1);
+ return 0;
+}
+
+SEC("classifier/1")
+int bpf_func_1(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, 2);
+ return 1;
+}
+
+SEC("classifier/2")
+int bpf_func_2(struct __sk_buff *skb)
+{
+ return 2;
+}
+
+SEC("classifier/3")
+int bpf_func_3(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, 4);
+ return 3;
+}
+
+SEC("classifier/4")
+int bpf_func_4(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, 3);
+ return 4;
+}
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, 0);
+ /* Check multi-prog update. */
+ bpf_tail_call(skb, &jmp_table, 2);
+ /* Check tail call limit. */
+ bpf_tail_call(skb, &jmp_table, 3);
+ return 3;
+}
+
+char __license[] SEC("license") = "GPL";
+int _version SEC("version") = 1;
diff --git a/tools/testing/selftests/bpf/progs/tailcall3.c b/tools/testing/selftests/bpf/progs/tailcall3.c
new file mode 100644
index 000000000000..1ecae198b8c1
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall3.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+
+#include "bpf_helpers.h"
+
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 1);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+static volatile int count;
+
+SEC("classifier/0")
+int bpf_func_0(struct __sk_buff *skb)
+{
+ count++;
+ bpf_tail_call(skb, &jmp_table, 0);
+ return 1;
+}
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, 0);
+ return 0;
+}
+
+char __license[] SEC("license") = "GPL";
+int _version SEC("version") = 1;
diff --git a/tools/testing/selftests/bpf/progs/tailcall4.c b/tools/testing/selftests/bpf/progs/tailcall4.c
new file mode 100644
index 000000000000..499388758119
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall4.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+
+#include "bpf_helpers.h"
+
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 3);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+static volatile int selector;
+
+#define TAIL_FUNC(x) \
+ SEC("classifier/" #x) \
+ int bpf_func_##x(struct __sk_buff *skb) \
+ { \
+ return x; \
+ }
+TAIL_FUNC(0)
+TAIL_FUNC(1)
+TAIL_FUNC(2)
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+ bpf_tail_call(skb, &jmp_table, selector);
+ return 3;
+}
+
+char __license[] SEC("license") = "GPL";
+int _version SEC("version") = 1;
diff --git a/tools/testing/selftests/bpf/progs/tailcall5.c b/tools/testing/selftests/bpf/progs/tailcall5.c
new file mode 100644
index 000000000000..49c64eb53f19
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall5.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+
+#include "bpf_helpers.h"
+
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 3);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+static volatile int selector;
+
+#define TAIL_FUNC(x) \
+ SEC("classifier/" #x) \
+ int bpf_func_##x(struct __sk_buff *skb) \
+ { \
+ return x; \
+ }
+TAIL_FUNC(0)
+TAIL_FUNC(1)
+TAIL_FUNC(2)
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+ int idx = 0;
+
+ if (selector == 1234)
+ idx = 1;
+ else if (selector == 5678)
+ idx = 2;
+
+ bpf_tail_call(skb, &jmp_table, idx);
+ return 3;
+}
+
+char __license[] SEC("license") = "GPL";
+int _version SEC("version") = 1;
--
2.21.0
next prev parent reply other threads:[~2019-11-22 20:08 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-22 20:07 [PATCH bpf-next v2 0/8] Optimize BPF tail calls for direct jumps Daniel Borkmann
2019-11-22 20:07 ` [PATCH bpf-next v2 1/8] bpf, x86: generalize and extend bpf_arch_text_poke " Daniel Borkmann
2019-11-22 20:07 ` [PATCH bpf-next v2 2/8] bpf: move bpf_free_used_maps into sleepable section Daniel Borkmann
2019-11-22 20:07 ` [PATCH bpf-next v2 3/8] bpf: move owner type,jited info into array auxiliary data Daniel Borkmann
2019-11-22 20:07 ` [PATCH bpf-next v2 4/8] bpf: add initial poke descriptor table for jit images Daniel Borkmann
2019-11-22 20:07 ` [PATCH bpf-next v2 5/8] bpf: add poke dependency tracking for prog array maps Daniel Borkmann
2019-11-22 22:55 ` Andrii Nakryiko
2019-11-22 23:06 ` Daniel Borkmann
2019-11-22 23:10 ` Andrii Nakryiko
2019-11-22 20:07 ` [PATCH bpf-next v2 6/8] bpf: constant map key tracking for prog array pokes Daniel Borkmann
2019-11-22 22:57 ` Andrii Nakryiko
2019-11-23 10:39 ` Jakub Sitnicki
2019-11-22 20:08 ` [PATCH bpf-next v2 7/8] bpf, x86: emit patchable direct jump as tail call Daniel Borkmann
2019-11-22 23:09 ` Andrii Nakryiko
2019-11-22 23:25 ` Daniel Borkmann
2019-11-23 2:28 ` Alexei Starovoitov
2019-11-23 5:00 ` Andrii Nakryiko
2019-11-23 6:18 ` Alexei Starovoitov
2019-11-23 9:24 ` Daniel Borkmann
2019-11-22 20:08 ` Daniel Borkmann [this message]
2019-11-22 23:14 ` [PATCH bpf-next v2 8/8] bpf, testing: add various tail call test cases Andrii Nakryiko
2019-11-23 2:22 ` [PATCH bpf-next v2 0/8] Optimize BPF tail calls for direct jumps Alexei Starovoitov
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