selftests/bpf: Convert map_ptr_kern test to use light skeleton.

To exercise CO-RE in the kernel further convert map_ptr_kern
test to light skeleton.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211201181040.23337-15-alexei.starovoitov@gmail.com

tools/testing/selftests/bpf/Makefile

@@ -325,7 +325,8 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h		\
 		linked_vars.skel.h linked_maps.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
+	test_ringbuf.c atomics.c trace_printk.c trace_vprintk.c \
+	map_ptr_kern.c
 # Generate both light skeleton and libbpf skeleton for these
 LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c kfunc_call_test_subprog.c
 SKEL_BLACKLIST += $$(LSKELS)

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

@@ -4,31 +4,29 @@
 #include <test_progs.h>
 #include <network_helpers.h>
 
-#include "map_ptr_kern.skel.h"
+#include "map_ptr_kern.lskel.h"
 
 void test_map_ptr(void)
 {
-	struct map_ptr_kern *skel;
+	struct map_ptr_kern_lskel *skel;
 	__u32 duration = 0, retval;
 	char buf[128];
 	int err;
 	int page_size = getpagesize();
 
-	skel = map_ptr_kern__open();
+	skel = map_ptr_kern_lskel__open();
 	if (!ASSERT_OK_PTR(skel, "skel_open"))
 		return;
 
-	err = bpf_map__set_max_entries(skel->maps.m_ringbuf, page_size);
-	if (!ASSERT_OK(err, "bpf_map__set_max_entries"))
-		goto cleanup;
+	skel->maps.m_ringbuf.max_entries = page_size;
 
-	err = map_ptr_kern__load(skel);
+	err = map_ptr_kern_lskel__load(skel);
 	if (!ASSERT_OK(err, "skel_load"))
 		goto cleanup;
 
 	skel->bss->page_size = page_size;
 
-	err = bpf_prog_test_run(bpf_program__fd(skel->progs.cg_skb), 1, &pkt_v4,
+	err = bpf_prog_test_run(skel->progs.cg_skb.prog_fd, 1, &pkt_v4,
 				sizeof(pkt_v4), buf, NULL, &retval, NULL);
 
 	if (CHECK(err, "test_run", "err=%d errno=%d\n", err, errno))
@@ -39,5 +37,5 @@ void test_map_ptr(void)
 		goto cleanup;
 
 cleanup:
-	map_ptr_kern__destroy(skel);
+	map_ptr_kern_lskel__destroy(skel);
 }