4 files changed, 257 insertions, 2 deletions

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 059d64a0f897..f802de526f57 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -23,7 +23,8 @@ $(TEST_CUSTOM_PROGS): $(OUTPUT)/%: %.c
 TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
 	test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
 	test_sock test_btf test_sockmap test_lirc_mode2_user get_cgroup_id_user \
-	test_socket_cookie test_cgroup_storage test_select_reuseport test_section_names
+	test_socket_cookie test_cgroup_storage test_select_reuseport test_section_names \
+	test_netcnt
 
 TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
 	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \
@@ -35,7 +36,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
 	test_get_stack_rawtp.o test_sockmap_kern.o test_sockhash_kern.o \
 	test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
 	get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o \
-	test_skb_cgroup_id_kern.o bpf_flow.o
+	test_skb_cgroup_id_kern.o bpf_flow.o netcnt_prog.o
 
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \
@@ -72,6 +73,7 @@ $(OUTPUT)/test_tcpbpf_user: cgroup_helpers.c
 $(OUTPUT)/test_progs: trace_helpers.c
 $(OUTPUT)/get_cgroup_id_user: cgroup_helpers.c
 $(OUTPUT)/test_cgroup_storage: cgroup_helpers.c
+$(OUTPUT)/test_netcnt: cgroup_helpers.c
 
 .PHONY: force
 
diff --git a/tools/testing/selftests/bpf/netcnt_common.h b/tools/testing/selftests/bpf/netcnt_common.h
new file mode 100644
index 000000000000..81084c1c2c23
--- /dev/null
+++ b/tools/testing/selftests/bpf/netcnt_common.h
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef __NETCNT_COMMON_H
+#define __NETCNT_COMMON_H
+
+#include <linux/types.h>
+
+#define MAX_PERCPU_PACKETS 32
+
+struct percpu_net_cnt {
+	__u64 packets;
+	__u64 bytes;
+
+	__u64 prev_ts;
+
+	__u64 prev_packets;
+	__u64 prev_bytes;
+};
+
+struct net_cnt {
+	__u64 packets;
+	__u64 bytes;
+};
+
+#endif
diff --git a/tools/testing/selftests/bpf/netcnt_prog.c b/tools/testing/selftests/bpf/netcnt_prog.c
new file mode 100644
index 000000000000..1198abca1360
--- /dev/null
+++ b/tools/testing/selftests/bpf/netcnt_prog.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <linux/version.h>
+
+#include "bpf_helpers.h"
+#include "netcnt_common.h"
+
+#define MAX_BPS	(3 * 1024 * 1024)
+
+#define REFRESH_TIME_NS	100000000
+#define NS_PER_SEC	1000000000
+
+struct bpf_map_def SEC("maps") percpu_netcnt = {
+	.type = BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
+	.key_size = sizeof(struct bpf_cgroup_storage_key),
+	.value_size = sizeof(struct percpu_net_cnt),
+};
+
+struct bpf_map_def SEC("maps") netcnt = {
+	.type = BPF_MAP_TYPE_CGROUP_STORAGE,
+	.key_size = sizeof(struct bpf_cgroup_storage_key),
+	.value_size = sizeof(struct net_cnt),
+};
+
+SEC("cgroup/skb")
+int bpf_nextcnt(struct __sk_buff *skb)
+{
+	struct percpu_net_cnt *percpu_cnt;
+	char fmt[] = "%d %llu %llu\n";
+	struct net_cnt *cnt;
+	__u64 ts, dt;
+	int ret;
+
+	cnt = bpf_get_local_storage(&netcnt, 0);
+	percpu_cnt = bpf_get_local_storage(&percpu_netcnt, 0);
+
+	percpu_cnt->packets++;
+	percpu_cnt->bytes += skb->len;
+
+	if (percpu_cnt->packets > MAX_PERCPU_PACKETS) {
+		__sync_fetch_and_add(&cnt->packets,
+				     percpu_cnt->packets);
+		percpu_cnt->packets = 0;
+
+		__sync_fetch_and_add(&cnt->bytes,
+				     percpu_cnt->bytes);
+		percpu_cnt->bytes = 0;
+	}
+
+	ts = bpf_ktime_get_ns();
+	dt = ts - percpu_cnt->prev_ts;
+
+	dt *= MAX_BPS;
+	dt /= NS_PER_SEC;
+
+	if (cnt->bytes + percpu_cnt->bytes - percpu_cnt->prev_bytes < dt)
+		ret = 1;
+	else
+		ret = 0;
+
+	if (dt > REFRESH_TIME_NS) {
+		percpu_cnt->prev_ts = ts;
+		percpu_cnt->prev_packets = cnt->packets;
+		percpu_cnt->prev_bytes = cnt->bytes;
+	}
+
+	return !!ret;
+}
+
+char _license[] SEC("license") = "GPL";
+__u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/tools/testing/selftests/bpf/test_netcnt.c b/tools/testing/selftests/bpf/test_netcnt.c
new file mode 100644
index 000000000000..7887df693399
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_netcnt.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <sys/sysinfo.h>
+#include <sys/time.h>
+
+#include <linux/bpf.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "cgroup_helpers.h"
+#include "bpf_rlimit.h"
+#include "netcnt_common.h"
+
+#define BPF_PROG "./netcnt_prog.o"
+#define TEST_CGROUP "/test-network-counters/"
+
+static int bpf_find_map(const char *test, struct bpf_object *obj,
+			const char *name)
+{
+	struct bpf_map *map;
+
+	map = bpf_object__find_map_by_name(obj, name);
+	if (!map) {
+		printf("%s:FAIL:map '%s' not found\n", test, name);
+		return -1;
+	}
+	return bpf_map__fd(map);
+}
+
+int main(int argc, char **argv)
+{
+	struct percpu_net_cnt *percpu_netcnt;
+	struct bpf_cgroup_storage_key key;
+	int map_fd, percpu_map_fd;
+	int error = EXIT_FAILURE;
+	struct net_cnt netcnt;
+	struct bpf_object *obj;
+	int prog_fd, cgroup_fd;
+	unsigned long packets;
+	unsigned long bytes;
+	int cpu, nproc;
+	__u32 prog_cnt;
+
+	nproc = get_nprocs_conf();
+	percpu_netcnt = malloc(sizeof(*percpu_netcnt) * nproc);
+	if (!percpu_netcnt) {
+		printf("Not enough memory for per-cpu area (%d cpus)\n", nproc);
+		goto err;
+	}
+
+	if (bpf_prog_load(BPF_PROG, BPF_PROG_TYPE_CGROUP_SKB,
+			  &obj, &prog_fd)) {
+		printf("Failed to load bpf program\n");
+		goto out;
+	}
+
+	if (setup_cgroup_environment()) {
+		printf("Failed to load bpf program\n");
+		goto err;
+	}
+
+	/* Create a cgroup, get fd, and join it */
+	cgroup_fd = create_and_get_cgroup(TEST_CGROUP);
+	if (!cgroup_fd) {
+		printf("Failed to create test cgroup\n");
+		goto err;
+	}
+
+	if (join_cgroup(TEST_CGROUP)) {
+		printf("Failed to join cgroup\n");
+		goto err;
+	}
+
+	/* Attach bpf program */
+	if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_INET_EGRESS, 0)) {
+		printf("Failed to attach bpf program");
+		goto err;
+	}
+
+	assert(system("ping localhost -6 -c 10000 -f -q > /dev/null") == 0);
+
+	if (bpf_prog_query(cgroup_fd, BPF_CGROUP_INET_EGRESS, 0, NULL, NULL,
+			   &prog_cnt)) {
+		printf("Failed to query attached programs");
+		goto err;
+	}
+
+	map_fd = bpf_find_map(__func__, obj, "netcnt");
+	if (map_fd < 0) {
+		printf("Failed to find bpf map with net counters");
+		goto err;
+	}
+
+	percpu_map_fd = bpf_find_map(__func__, obj, "percpu_netcnt");
+	if (percpu_map_fd < 0) {
+		printf("Failed to find bpf map with percpu net counters");
+		goto err;
+	}
+
+	if (bpf_map_get_next_key(map_fd, NULL, &key)) {
+		printf("Failed to get key in cgroup storage\n");
+		goto err;
+	}
+
+	if (bpf_map_lookup_elem(map_fd, &key, &netcnt)) {
+		printf("Failed to lookup cgroup storage\n");
+		goto err;
+	}
+
+	if (bpf_map_lookup_elem(percpu_map_fd, &key, &percpu_netcnt[0])) {
+		printf("Failed to lookup percpu cgroup storage\n");
+		goto err;
+	}
+
+	/* Some packets can be still in per-cpu cache, but not more than
+	 * MAX_PERCPU_PACKETS.
+	 */
+	packets = netcnt.packets;
+	bytes = netcnt.bytes;
+	for (cpu = 0; cpu < nproc; cpu++) {
+		if (percpu_netcnt[cpu].packets > MAX_PERCPU_PACKETS) {
+			printf("Unexpected percpu value: %llu\n",
+			       percpu_netcnt[cpu].packets);
+			goto err;
+		}
+
+		packets += percpu_netcnt[cpu].packets;
+		bytes += percpu_netcnt[cpu].bytes;
+	}
+
+	/* No packets should be lost */
+	if (packets != 10000) {
+		printf("Unexpected packet count: %lu\n", packets);
+		goto err;
+	}
+
+	/* Let's check that bytes counter matches the number of packets
+	 * multiplied by the size of ipv6 ICMP packet.
+	 */
+	if (bytes != packets * 104) {
+		printf("Unexpected bytes count: %lu\n", bytes);
+		goto err;
+	}
+
+	error = 0;
+	printf("test_netcnt:PASS\n");
+
+err:
+	cleanup_cgroup_environment();
+	free(percpu_netcnt);
+
+out:
+	return error;
+}