From: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
Add a new test where some of the packets are not passed to the AF_XDP
socket and instead get a XDP_DROP verdict. This is important as it
tests the recycling mechanism of the buffer pool. If a packet is not
sent to the AF_XDP socket, the buffer the packet resides in is instead
recycled so it can be used again without the round-trip to user
space. The test introduces a new XDP program that drops every other
packet.
Signed-off-by: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
---
tools/testing/selftests/bpf/Makefile | 2 +-
.../selftests/bpf/progs/xsk_xdp_drop.c | 25 ++++++++++
tools/testing/selftests/bpf/xskxceiver.c | 48 +++++++++++++++++--
tools/testing/selftests/bpf/xskxceiver.h | 3 ++
4 files changed, 72 insertions(+), 6 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/xsk_xdp_drop.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 42e15b5a34a7..77ef8a8e6db4 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -240,7 +240,7 @@ $(OUTPUT)/flow_dissector_load: $(TESTING_HELPERS)
$(OUTPUT)/test_maps: $(TESTING_HELPERS)
$(OUTPUT)/test_verifier: $(TESTING_HELPERS) $(CAP_HELPERS)
$(OUTPUT)/xsk.o: $(BPFOBJ)
-$(OUTPUT)/xskxceiver: $(OUTPUT)/xsk.o $(OUTPUT)/xsk_def_prog.skel.h
+$(OUTPUT)/xskxceiver: $(OUTPUT)/xsk.o $(OUTPUT)/xsk_def_prog.skel.h $(OUTPUT)/xsk_xdp_drop.skel.h
BPFTOOL ?= $(DEFAULT_BPFTOOL)
$(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) \
diff --git a/tools/testing/selftests/bpf/progs/xsk_xdp_drop.c b/tools/testing/selftests/bpf/progs/xsk_xdp_drop.c
new file mode 100644
index 000000000000..12a12b0d9fc1
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/xsk_xdp_drop.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022 Intel */
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+struct {
+ __uint(type, BPF_MAP_TYPE_XSKMAP);
+ __uint(max_entries, 1);
+ __uint(key_size, sizeof(int));
+ __uint(value_size, sizeof(int));
+} xsk SEC(".maps");
+
+static unsigned int idx;
+
+SEC("xdp") int xsk_xdp_drop(struct xdp_md *xdp)
+{
+ /* Drop every other packet */
+ if (idx++ % 2)
+ return XDP_DROP;
+
+ return bpf_redirect_map(&xsk, 0, XDP_DROP);
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
index 0cda4e3f1871..522dc1d69c17 100644
--- a/tools/testing/selftests/bpf/xskxceiver.c
+++ b/tools/testing/selftests/bpf/xskxceiver.c
@@ -1654,18 +1654,53 @@ static void testapp_invalid_desc(struct test_spec *test)
pkt_stream_restore_default(test);
}
-static int xsk_load_xdp_program(struct ifobject *ifobj)
+static void testapp_xdp_drop(struct test_spec *test)
+{
+ struct ifobject *ifobj = test->ifobj_rx;
+ int err;
+
+ test_spec_set_name(test, "XDP_CONSUMES_SOME_PACKETS");
+ xsk_detach_xdp_program(ifobj->ifindex, ifobj->xdp_flags);
+ err = xsk_attach_xdp_program(ifobj->xdp_drop->progs.xsk_xdp_drop, ifobj->ifindex,
+ ifobj->xdp_flags);
+ if (err) {
+ printf("Error attaching XDP_DROP program\n");
+ test->fail = true;
+ return;
+ }
+ ifobj->xskmap = ifobj->xdp_drop->maps.xsk;
+
+ pkt_stream_receive_half(test);
+ testapp_validate_traffic(test);
+
+ pkt_stream_restore_default(test);
+ xsk_detach_xdp_program(ifobj->ifindex, ifobj->xdp_flags);
+ err = xsk_attach_xdp_program(ifobj->def_prog->progs.xsk_def_prog, ifobj->ifindex,
+ ifobj->xdp_flags);
+ if (err) {
+ printf("Error restoring default XDP program\n");
+ exit_with_error(-err);
+ }
+ ifobj->xskmap = ifobj->def_prog->maps.xsk;
+}
+
+static int xsk_load_xdp_programs(struct ifobject *ifobj)
{
ifobj->def_prog = xsk_def_prog__open_and_load();
if (libbpf_get_error(ifobj->def_prog))
return libbpf_get_error(ifobj->def_prog);
+ ifobj->xdp_drop = xsk_xdp_drop__open_and_load();
+ if (libbpf_get_error(ifobj->xdp_drop))
+ return libbpf_get_error(ifobj->xdp_drop);
+
return 0;
}
-static void xsk_unload_xdp_program(struct ifobject *ifobj)
+static void xsk_unload_xdp_programs(struct ifobject *ifobj)
{
xsk_def_prog__destroy(ifobj->def_prog);
+ xsk_xdp_drop__destroy(ifobj->xdp_drop);
}
static void init_iface(struct ifobject *ifobj, const char *dst_mac, const char *src_mac,
@@ -1692,7 +1727,7 @@ static void init_iface(struct ifobject *ifobj, const char *dst_mac, const char *
if (!load_xdp)
return;
- err = xsk_load_xdp_program(ifobj);
+ err = xsk_load_xdp_programs(ifobj);
if (err) {
printf("Error loading XDP program\n");
exit_with_error(err);
@@ -1804,6 +1839,9 @@ static void run_pkt_test(struct test_spec *test, enum test_mode mode, enum test_
case TEST_TYPE_HEADROOM:
testapp_headroom(test);
break;
+ case TEST_TYPE_XDP_CONSUMES_PACKETS:
+ testapp_xdp_drop(test);
+ break;
default:
break;
}
@@ -1971,8 +2009,8 @@ int main(int argc, char **argv)
pkt_stream_delete(tx_pkt_stream_default);
pkt_stream_delete(rx_pkt_stream_default);
- xsk_unload_xdp_program(ifobj_tx);
- xsk_unload_xdp_program(ifobj_rx);
+ xsk_unload_xdp_programs(ifobj_tx);
+ xsk_unload_xdp_programs(ifobj_rx);
ifobject_delete(ifobj_tx);
ifobject_delete(ifobj_rx);
diff --git a/tools/testing/selftests/bpf/xskxceiver.h b/tools/testing/selftests/bpf/xskxceiver.h
index eb6355bcc143..3483ac240b2e 100644
--- a/tools/testing/selftests/bpf/xskxceiver.h
+++ b/tools/testing/selftests/bpf/xskxceiver.h
@@ -6,6 +6,7 @@
#define XSKXCEIVER_H_
#include "xsk_def_prog.skel.h"
+#include "xsk_xdp_drop.skel.h"
#ifndef SOL_XDP
#define SOL_XDP 283
@@ -87,6 +88,7 @@ enum test_type {
TEST_TYPE_STATS_RX_FULL,
TEST_TYPE_STATS_FILL_EMPTY,
TEST_TYPE_BPF_RES,
+ TEST_TYPE_XDP_CONSUMES_PACKETS,
TEST_TYPE_MAX
};
@@ -141,6 +143,7 @@ struct ifobject {
validation_func_t validation_func;
struct pkt_stream *pkt_stream;
struct xsk_def_prog *def_prog;
+ struct xsk_xdp_drop *xdp_drop;
struct bpf_map *xskmap;
int ifindex;
u32 dst_ip;
--
2.34.1
