On 7/9/20 3:30 AM, Hangbin Liu wrote:
This is a sample for xdp multicast. In the sample we could forward all
packets between given interfaces.
v5: add a null_map as we have strict the arg2 to ARG_CONST_MAP_PTR.
Move the testing part to bpf selftest in next patch.
v4: no update.
v3: add rxcnt map to show the packet transmit speed.
v2: no update.
Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx>
---
samples/bpf/Makefile | 3 +
samples/bpf/xdp_redirect_map_multi_kern.c | 57 ++++++++
samples/bpf/xdp_redirect_map_multi_user.c | 166 ++++++++++++++++++++++
3 files changed, 226 insertions(+)
create mode 100644 samples/bpf/xdp_redirect_map_multi_kern.c
create mode 100644 samples/bpf/xdp_redirect_map_multi_user.c
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index f87ee02073ba..fddca6cb76b8 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -41,6 +41,7 @@ tprogs-y += test_map_in_map
tprogs-y += per_socket_stats_example
tprogs-y += xdp_redirect
tprogs-y += xdp_redirect_map
+tprogs-y += xdp_redirect_map_multi
tprogs-y += xdp_redirect_cpu
tprogs-y += xdp_monitor
tprogs-y += xdp_rxq_info
@@ -97,6 +98,7 @@ test_map_in_map-objs := test_map_in_map_user.o
per_socket_stats_example-objs := cookie_uid_helper_example.o
xdp_redirect-objs := xdp_redirect_user.o
xdp_redirect_map-objs := xdp_redirect_map_user.o
+xdp_redirect_map_multi-objs := xdp_redirect_map_multi_user.o
xdp_redirect_cpu-objs := bpf_load.o xdp_redirect_cpu_user.o
xdp_monitor-objs := bpf_load.o xdp_monitor_user.o
xdp_rxq_info-objs := xdp_rxq_info_user.o
@@ -156,6 +158,7 @@ always-y += tcp_tos_reflect_kern.o
always-y += tcp_dumpstats_kern.o
always-y += xdp_redirect_kern.o
always-y += xdp_redirect_map_kern.o
+always-y += xdp_redirect_map_multi_kern.o
always-y += xdp_redirect_cpu_kern.o
always-y += xdp_monitor_kern.o
always-y += xdp_rxq_info_kern.o
diff --git a/samples/bpf/xdp_redirect_map_multi_kern.c b/samples/bpf/xdp_redirect_map_multi_kern.c
new file mode 100644
index 000000000000..cc7ebaedf55a
--- /dev/null
+++ b/samples/bpf/xdp_redirect_map_multi_kern.c
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#define KBUILD_MODNAME "foo"
+#include <uapi/linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+struct bpf_map_def SEC("maps") forward_map = {
+ .type = BPF_MAP_TYPE_DEVMAP_HASH,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(int),
+ .max_entries = 256,
+};
+
+struct bpf_map_def SEC("maps") null_map = {
+ .type = BPF_MAP_TYPE_DEVMAP_HASH,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(int),
+ .max_entries = 1,
+};
+
+struct bpf_map_def SEC("maps") rxcnt = {
+ .type = BPF_MAP_TYPE_PERCPU_ARRAY,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(long),
+ .max_entries = 1,
+};
+
+SEC("xdp_redirect_map_multi")
+int xdp_redirect_map_multi_prog(struct xdp_md *ctx)
+{
+ long *value;
+ u32 key = 0;
+
+ /* count packet in global counter */
+ value = bpf_map_lookup_elem(&rxcnt, &key);
+ if (value)
+ *value += 1;
+
+ return bpf_redirect_map_multi(&forward_map, &null_map,
+ BPF_F_EXCLUDE_INGRESS);
Why not extending to allow use-case like ...
return bpf_redirect_map_multi(&fwd_map, NULL, BPF_F_EXCLUDE_INGRESS);
... instead of requiring a dummy/'null' map?
Thanks,
Daniel
