[RFC PATCH 16/16] bpf: tools: dbg patch to turn on debugging and add primitive examples

[John Fastabend <john.fastabend@gmail.com>]

While developing this I found it useful to always have the log
output when dealing with bpftool. This is a quick hack to enable
it but we should add a '-v' option shortly.

Then add a set of good and bad loop examples to test with. These
are all very basic at the moment but will get better soon.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
---
 tools/lib/bpf/bpf.c    |    2 +-
 tools/lib/bpf/libbpf.c |    7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 9ddc89d..b1d2199 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -200,7 +200,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
 	attr.license = ptr_to_u64(load_attr->license);
 	attr.log_buf = ptr_to_u64(NULL);
 	attr.log_size = 0;
-	attr.log_level = 0;
+	attr.log_level = 1;
 	attr.kern_version = load_attr->kern_version;
 	attr.prog_ifindex = load_attr->prog_ifindex;
 	memcpy(attr.prog_name, load_attr->name,
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index b1a60ac..34ff173 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1304,6 +1304,13 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
 	if (ret >= 0) {
 		*pfd = ret;
 		ret = 0;
+
+		pr_warning("load bpf program succesful\n");
+		if (log_buf && log_buf[0] != '\0') {
+			pr_warning("-- BEGIN DUMP LOG ---\n");
+			pr_warning("\n%s\n", log_buf);
+			pr_warning("-- END LOG --\n");
+		}
 		goto out;
 	}