selftests/bpf: Add weak/typeless ksym test for light skeleton

Also, avoid using CO-RE features, as lskel doesn't support CO-RE, yet.
Include both light and libbpf skeleton in same file to test both of them
together.

In c48e51c ("bpf: selftests: Add selftests for module kfunc support"),
I added support for generating both lskel and libbpf skel for a BPF
object, however the name parameter for bpftool caused collisions when
included in same file together. This meant that every test needed a
separate file for a libbpf/light skeleton separation instead of
subtests.

Change that by appending a "_lskel" suffix to the name for files using
light skeleton, and convert all existing users.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211028063501.2239335-7-memxor@gmail.com

tools/testing/selftests/bpf/Makefile

@@ -325,7 +325,7 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h		\
 LSKELS := kfunc_call_test.c fentry_test.c fexit_test.c fexit_sleep.c \
 	test_ringbuf.c atomics.c trace_printk.c trace_vprintk.c
 # Generate both light skeleton and libbpf skeleton for these
-LSKELS_EXTRA := test_ksyms_module.c
+LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c
 SKEL_BLACKLIST += $$(LSKELS)
 
 test_static_linked.skel.h-deps := test_static_linked1.o test_static_linked2.o
@@ -404,7 +404,7 @@ $(TRUNNER_BPF_LSKELS): %.lskel.h: %.o $(BPFTOOL) | $(TRUNNER_OUTPUT)
 	$(Q)$$(BPFTOOL) gen object $$(<:.o=.linked2.o) $$(<:.o=.linked1.o)
 	$(Q)$$(BPFTOOL) gen object $$(<:.o=.linked3.o) $$(<:.o=.linked2.o)
 	$(Q)diff $$(<:.o=.linked2.o) $$(<:.o=.linked3.o)
-	$(Q)$$(BPFTOOL) gen skeleton -L $$(<:.o=.linked3.o) name $$(notdir $$(<:.o=)) > $$@
+	$(Q)$$(BPFTOOL) gen skeleton -L $$(<:.o=.linked3.o) name $$(notdir $$(<:.o=_lskel)) > $$@
 
 $(TRUNNER_BPF_SKELS_LINKED): $(TRUNNER_BPF_OBJS) $(BPFTOOL) | $(TRUNNER_OUTPUT)
 	$$(call msg,LINK-BPF,$(TRUNNER_BINARY),$$(@:.skel.h=.o))

tools/testing/selftests/bpf/prog_tests/atomics.c

@@ -4,13 +4,13 @@
 
 #include "atomics.lskel.h"
 
-static void test_add(struct atomics *skel)
+static void test_add(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__add__attach(skel);
+	link_fd = atomics_lskel__add__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(add)"))
 		return;
 
@@ -36,13 +36,13 @@ static void test_add(struct atomics *skel)
 	close(link_fd);
 }
 
-static void test_sub(struct atomics *skel)
+static void test_sub(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__sub__attach(skel);
+	link_fd = atomics_lskel__sub__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(sub)"))
 		return;
 
@@ -69,13 +69,13 @@ static void test_sub(struct atomics *skel)
 	close(link_fd);
 }
 
-static void test_and(struct atomics *skel)
+static void test_and(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__and__attach(skel);
+	link_fd = atomics_lskel__and__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(and)"))
 		return;
 
@@ -97,13 +97,13 @@ static void test_and(struct atomics *skel)
 	close(link_fd);
 }
 
-static void test_or(struct atomics *skel)
+static void test_or(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__or__attach(skel);
+	link_fd = atomics_lskel__or__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(or)"))
 		return;
 
@@ -126,13 +126,13 @@ static void test_or(struct atomics *skel)
 	close(link_fd);
 }
 
-static void test_xor(struct atomics *skel)
+static void test_xor(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__xor__attach(skel);
+	link_fd = atomics_lskel__xor__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(xor)"))
 		return;
 
@@ -154,13 +154,13 @@ static void test_xor(struct atomics *skel)
 	close(link_fd);
 }
 
-static void test_cmpxchg(struct atomics *skel)
+static void test_cmpxchg(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__cmpxchg__attach(skel);
+	link_fd = atomics_lskel__cmpxchg__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(cmpxchg)"))
 		return;
 
@@ -183,13 +183,13 @@ static void test_cmpxchg(struct atomics *skel)
 	close(link_fd);
 }
 
-static void test_xchg(struct atomics *skel)
+static void test_xchg(struct atomics_lskel *skel)
 {
 	int err, prog_fd;
 	__u32 duration = 0, retval;
 	int link_fd;
 
-	link_fd = atomics__xchg__attach(skel);
+	link_fd = atomics_lskel__xchg__attach(skel);
 	if (!ASSERT_GT(link_fd, 0, "attach(xchg)"))
 		return;
 
@@ -212,10 +212,10 @@ static void test_xchg(struct atomics *skel)
 
 void test_atomics(void)
 {
-	struct atomics *skel;
+	struct atomics_lskel *skel;
 	__u32 duration = 0;
 
-	skel = atomics__open_and_load();
+	skel = atomics_lskel__open_and_load();
 	if (CHECK(!skel, "skel_load", "atomics skeleton failed\n"))
 		return;
 
@@ -243,5 +243,5 @@ void test_atomics(void)
 		test_xchg(skel);
 
 cleanup:
-	atomics__destroy(skel);
+	atomics_lskel__destroy(skel);
 }

tools/testing/selftests/bpf/prog_tests/fentry_fexit.c

@@ -6,23 +6,23 @@
 
 void test_fentry_fexit(void)
 {
-	struct fentry_test *fentry_skel = NULL;
-	struct fexit_test *fexit_skel = NULL;
+	struct fentry_test_lskel *fentry_skel = NULL;
+	struct fexit_test_lskel *fexit_skel = NULL;
 	__u64 *fentry_res, *fexit_res;
 	__u32 duration = 0, retval;
 	int err, prog_fd, i;
 
-	fentry_skel = fentry_test__open_and_load();
+	fentry_skel = fentry_test_lskel__open_and_load();
 	if (CHECK(!fentry_skel, "fentry_skel_load", "fentry skeleton failed\n"))
 		goto close_prog;
-	fexit_skel = fexit_test__open_and_load();
+	fexit_skel = fexit_test_lskel__open_and_load();
 	if (CHECK(!fexit_skel, "fexit_skel_load", "fexit skeleton failed\n"))
 		goto close_prog;
 
-	err = fentry_test__attach(fentry_skel);
+	err = fentry_test_lskel__attach(fentry_skel);
 	if (CHECK(err, "fentry_attach", "fentry attach failed: %d\n", err))
 		goto close_prog;
-	err = fexit_test__attach(fexit_skel);
+	err = fexit_test_lskel__attach(fexit_skel);
 	if (CHECK(err, "fexit_attach", "fexit attach failed: %d\n", err))
 		goto close_prog;
 
@@ -44,6 +44,6 @@ void test_fentry_fexit(void)
 	}
 
 close_prog:
-	fentry_test__destroy(fentry_skel);
-	fexit_test__destroy(fexit_skel);
+	fentry_test_lskel__destroy(fentry_skel);
+	fexit_test_lskel__destroy(fexit_skel);
 }

tools/testing/selftests/bpf/prog_tests/fentry_test.c

@@ -3,19 +3,19 @@
 #include <test_progs.h>
 #include "fentry_test.lskel.h"
 
-static int fentry_test(struct fentry_test *fentry_skel)
+static int fentry_test(struct fentry_test_lskel *fentry_skel)
 {
 	int err, prog_fd, i;
 	__u32 duration = 0, retval;
 	int link_fd;
 	__u64 *result;
 
-	err = fentry_test__attach(fentry_skel);
+	err = fentry_test_lskel__attach(fentry_skel);
 	if (!ASSERT_OK(err, "fentry_attach"))
 		return err;
 
 	/* Check that already linked program can't be attached again. */
-	link_fd = fentry_test__test1__attach(fentry_skel);
+	link_fd = fentry_test_lskel__test1__attach(fentry_skel);
 	if (!ASSERT_LT(link_fd, 0, "fentry_attach_link"))
 		return -1;
 
@@ -31,7 +31,7 @@ static int fentry_test(struct fentry_test *fentry_skel)
 			return -1;
 	}
 
-	fentry_test__detach(fentry_skel);
+	fentry_test_lskel__detach(fentry_skel);
 
 	/* zero results for re-attach test */
 	memset(fentry_skel->bss, 0, sizeof(*fentry_skel->bss));
@@ -40,10 +40,10 @@ static int fentry_test(struct fentry_test *fentry_skel)
 
 void test_fentry_test(void)
 {
-	struct fentry_test *fentry_skel = NULL;
+	struct fentry_test_lskel *fentry_skel = NULL;
 	int err;
 
-	fentry_skel = fentry_test__open_and_load();
+	fentry_skel = fentry_test_lskel__open_and_load();
 	if (!ASSERT_OK_PTR(fentry_skel, "fentry_skel_load"))
 		goto cleanup;
 
@@ -55,5 +55,5 @@ void test_fentry_test(void)
 	ASSERT_OK(err, "fentry_second_attach");
 
 cleanup:
-	fentry_test__destroy(fentry_skel);
+	fentry_test_lskel__destroy(fentry_skel);
 }

tools/testing/selftests/bpf/prog_tests/fexit_sleep.c

@@ -10,7 +10,7 @@
 
 static int do_sleep(void *skel)
 {
-	struct fexit_sleep *fexit_skel = skel;
+	struct fexit_sleep_lskel *fexit_skel = skel;
 	struct timespec ts1 = { .tv_nsec = 1 };
 	struct timespec ts2 = { .tv_sec = 10 };
 
@@ -25,16 +25,16 @@ static char child_stack[STACK_SIZE];
 
 void test_fexit_sleep(void)
 {
-	struct fexit_sleep *fexit_skel = NULL;
+	struct fexit_sleep_lskel *fexit_skel = NULL;
 	int wstatus, duration = 0;
 	pid_t cpid;
 	int err, fexit_cnt;
 
-	fexit_skel = fexit_sleep__open_and_load();
+	fexit_skel = fexit_sleep_lskel__open_and_load();
 	if (CHECK(!fexit_skel, "fexit_skel_load", "fexit skeleton failed\n"))
 		goto cleanup;
 
-	err = fexit_sleep__attach(fexit_skel);
+	err = fexit_sleep_lskel__attach(fexit_skel);
 	if (CHECK(err, "fexit_attach", "fexit attach failed: %d\n", err))
 		goto cleanup;
 
@@ -60,7 +60,7 @@ void test_fexit_sleep(void)
 	 */
 	close(fexit_skel->progs.nanosleep_fentry.prog_fd);
 	close(fexit_skel->progs.nanosleep_fexit.prog_fd);
-	fexit_sleep__detach(fexit_skel);
+	fexit_sleep_lskel__detach(fexit_skel);
 
 	/* kill the thread to unwind sys_nanosleep stack through the trampoline */
 	kill(cpid, 9);
@@ -78,5 +78,5 @@ void test_fexit_sleep(void)
 		goto cleanup;
 
 cleanup:
-	fexit_sleep__destroy(fexit_skel);
+	fexit_sleep_lskel__destroy(fexit_skel);
 }

tools/testing/selftests/bpf/prog_tests/fexit_test.c

@@ -3,19 +3,19 @@
 #include <test_progs.h>
 #include "fexit_test.lskel.h"
 
-static int fexit_test(struct fexit_test *fexit_skel)
+static int fexit_test(struct fexit_test_lskel *fexit_skel)
 {
 	int err, prog_fd, i;
 	__u32 duration = 0, retval;
 	int link_fd;
 	__u64 *result;
 
-	err = fexit_test__attach(fexit_skel);
+	err = fexit_test_lskel__attach(fexit_skel);
 	if (!ASSERT_OK(err, "fexit_attach"))
 		return err;
 
 	/* Check that already linked program can't be attached again. */
-	link_fd = fexit_test__test1__attach(fexit_skel);
+	link_fd = fexit_test_lskel__test1__attach(fexit_skel);
 	if (!ASSERT_LT(link_fd, 0, "fexit_attach_link"))
 		return -1;
 
@@ -31,7 +31,7 @@ static int fexit_test(struct fexit_test *fexit_skel)
 			return -1;
 	}
 
-	fexit_test__detach(fexit_skel);
+	fexit_test_lskel__detach(fexit_skel);
 
 	/* zero results for re-attach test */
 	memset(fexit_skel->bss, 0, sizeof(*fexit_skel->bss));
@@ -40,10 +40,10 @@ static int fexit_test(struct fexit_test *fexit_skel)
 
 void test_fexit_test(void)
 {
-	struct fexit_test *fexit_skel = NULL;
+	struct fexit_test_lskel *fexit_skel = NULL;
 	int err;
 
-	fexit_skel = fexit_test__open_and_load();
+	fexit_skel = fexit_test_lskel__open_and_load();
 	if (!ASSERT_OK_PTR(fexit_skel, "fexit_skel_load"))
 		goto cleanup;
 
@@ -55,5 +55,5 @@ void test_fexit_test(void)
 	ASSERT_OK(err, "fexit_second_attach");
 
 cleanup:
-	fexit_test__destroy(fexit_skel);
+	fexit_test_lskel__destroy(fexit_skel);
 }

tools/testing/selftests/bpf/prog_tests/kfunc_call.c

@@ -7,10 +7,10 @@
 
 static void test_main(void)
 {
-	struct kfunc_call_test *skel;
+	struct kfunc_call_test_lskel *skel;
 	int prog_fd, retval, err;
 
-	skel = kfunc_call_test__open_and_load();
+	skel = kfunc_call_test_lskel__open_and_load();
 	if (!ASSERT_OK_PTR(skel, "skel"))
 		return;
 
@@ -26,7 +26,7 @@ static void test_main(void)
 	ASSERT_OK(err, "bpf_prog_test_run(test2)");
 	ASSERT_EQ(retval, 3, "test2-retval");
 
-	kfunc_call_test__destroy(skel);
+	kfunc_call_test_lskel__destroy(skel);
 }
 
 static void test_subprog(void)