Merge branch 'bpf-prog-testing-framework'

Alexei Starovoitov says:

====================
bpf: program testing framework

Development and testing of networking bpf programs is quite cumbersome.
Especially tricky are XDP programs that attach to real netdevices and
program development feels like working on the car engine while
the car is in motion.
Another problem is ongoing changes to upstream llvm core
that can introduce an optimization that verifier will not
recognize. llvm bpf backend tests have no ability to run the programs.
To improve this situation introduce BPF_PROG_TEST_RUN command
to test and performance benchmark bpf programs.
It achieves several goals:
- development of xdp and skb based bpf programs can be done
in a canned environment with unit tests
- program performance optimizations can be benchmarked outside of
networking core (without driver and skb costs)
- continuous testing of upstream changes is finally practical

Patches 4,5,6 add C based test cases of various complexity
to cover some sched_cls and xdp features. More tests will
be added in the future. The tests were run on centos7 only.

For now the framework supports only skb and xdp programs. In the future
it can be extended to socket_filter and tracing program types.

More details are in individual patches.

v1->v2:
- rename bpf_program_test_run->bpf_prog_test_run
- add missing #include <linux/bpf.h> since libbpf.h shouldn't depend
on prior includes
- reordered patches 3 and 4 to keep bisect clean
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 30 insertions, 3 deletions

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 9b58d20e8c93..f84c398c11f4 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -209,3 +209,27 @@ int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
 
 	return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
 }
+
+int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
+		      void *data_out, __u32 *size_out, __u32 *retval,
+		      __u32 *duration)
+{
+	union bpf_attr attr;
+	int ret;
+
+	bzero(&attr, sizeof(attr));
+	attr.test.prog_fd = prog_fd;
+	attr.test.data_in = ptr_to_u64(data);
+	attr.test.data_out = ptr_to_u64(data_out);
+	attr.test.data_size_in = size;
+	attr.test.repeat = repeat;
+
+	ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
+	if (size_out)
+		*size_out = attr.test.data_size_out;
+	if (retval)
+		*retval = attr.test.retval;
+	if (duration)
+		*duration = attr.test.duration;
+	return ret;
+}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 93f021932623..edb4daeff7a5 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -47,6 +47,8 @@ int bpf_obj_get(const char *pathname);
 int bpf_prog_attach(int prog_fd, int attachable_fd, enum bpf_attach_type type,
 		    unsigned int flags);
 int bpf_prog_detach(int attachable_fd, enum bpf_attach_type type);
-
+int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
+		      void *data_out, __u32 *size_out, __u32 *retval,
+		      __u32 *duration);
 
 #endif
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index ac6eb863b2a4..1a2c07eb7795 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1618,8 +1618,7 @@ int bpf_program__nth_fd(struct bpf_program *prog, int n)
 	return fd;
 }
 
-static void bpf_program__set_type(struct bpf_program *prog,
-				  enum bpf_prog_type type)
+void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type)
 {
 	prog->type = type;
 }
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index b30394f9947a..32c7252f734e 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -25,6 +25,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <sys/types.h>  // for size_t
+#include <linux/bpf.h>
 
 enum libbpf_errno {
 	__LIBBPF_ERRNO__START = 4000,
@@ -185,6 +186,7 @@ int bpf_program__set_sched_cls(struct bpf_program *prog);
 int bpf_program__set_sched_act(struct bpf_program *prog);
 int bpf_program__set_xdp(struct bpf_program *prog);
 int bpf_program__set_perf_event(struct bpf_program *prog);
+void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type);
 
 bool bpf_program__is_socket_filter(struct bpf_program *prog);
 bool bpf_program__is_tracepoint(struct bpf_program *prog);