[PATCH 07/12] selftests/net: Add test/benchmark for removing MKTs

From: Dmitry Safonov
Date: Thu Dec 14 2023 - 21:40:14 EST

Sample output:
> 1..36
> # 1106[lib/setup.c:207] rand seed 1660754406
> TAP version 13
> ok 1 Worst case connect 512 keys: min=0ms max=1ms mean=0.583329ms stddev=0.076376
> ok 2 Connect random-search 512 keys: min=0ms max=1ms mean=0.53412ms stddev=0.0516779
> ok 3 Worst case delete 512 keys: min=2ms max=11ms mean=6.04139ms stddev=0.245792
> ok 4 Add a new key 512 keys: min=0ms max=13ms mean=0.673415ms stddev=0.0820618
> ok 5 Remove random-search 512 keys: min=5ms max=9ms mean=6.65969ms stddev=0.258064
> ok 6 Remove async 512 keys: min=0ms max=0ms mean=0.041825ms stddev=0.0204512
> ok 7 Worst case connect 1024 keys: min=0ms max=2ms mean=0.520357ms stddev=0.0721358
> ok 8 Connect random-search 1024 keys: min=0ms max=2ms mean=0.535312ms stddev=0.0517355
> ok 9 Worst case delete 1024 keys: min=5ms max=9ms mean=8.27219ms stddev=0.287614
> ok 10 Add a new key 1024 keys: min=0ms max=1ms mean=0.688121ms stddev=0.0829531
> ok 11 Remove random-search 1024 keys: min=5ms max=9ms mean=8.37649ms stddev=0.289422
> ok 12 Remove async 1024 keys: min=0ms max=0ms mean=0.0457096ms stddev=0.0213798
> ok 13 Worst case connect 2048 keys: min=0ms max=2ms mean=0.748804ms stddev=0.0865335
> ok 14 Connect random-search 2048 keys: min=0ms max=2ms mean=0.782993ms stddev=0.0625697
> ok 15 Worst case delete 2048 keys: min=5ms max=10ms mean=8.23106ms stddev=0.286898
> ok 16 Add a new key 2048 keys: min=0ms max=1ms mean=0.812988ms stddev=0.0901658
> ok 17 Remove random-search 2048 keys: min=8ms max=9ms mean=8.84949ms stddev=0.297481
> ok 18 Remove async 2048 keys: min=0ms max=0ms mean=0.0297223ms stddev=0.0172402
> ok 19 Worst case connect 4096 keys: min=1ms max=5ms mean=1.53352ms stddev=0.123836
> ok 20 Connect random-search 4096 keys: min=1ms max=5ms mean=1.52226ms stddev=0.0872429
> ok 21 Worst case delete 4096 keys: min=5ms max=9ms mean=8.25874ms stddev=0.28738
> ok 22 Add a new key 4096 keys: min=0ms max=3ms mean=1.67382ms stddev=0.129376
> ok 23 Remove random-search 4096 keys: min=5ms max=10ms mean=8.26178ms stddev=0.287433
> ok 24 Remove async 4096 keys: min=0ms max=0ms mean=0.0340009ms stddev=0.0184393
> ok 25 Worst case connect 8192 keys: min=2ms max=4ms mean=2.86208ms stddev=0.169177
> ok 26 Connect random-search 8192 keys: min=2ms max=4ms mean=2.87592ms stddev=0.119915
> ok 27 Worst case delete 8192 keys: min=6ms max=11ms mean=7.55291ms stddev=0.274826
> ok 28 Add a new key 8192 keys: min=1ms max=5ms mean=2.56797ms stddev=0.160249
> ok 29 Remove random-search 8192 keys: min=5ms max=10ms mean=7.14002ms stddev=0.267208
> ok 30 Remove async 8192 keys: min=0ms max=0ms mean=0.0320066ms stddev=0.0178904
> ok 31 Worst case connect 16384 keys: min=5ms max=6ms mean=5.55334ms stddev=0.235655
> ok 32 Connect random-search 16384 keys: min=5ms max=6ms mean=5.52614ms stddev=0.166225
> ok 33 Worst case delete 16384 keys: min=5ms max=11ms mean=7.39109ms stddev=0.271866
> ok 34 Add a new key 16384 keys: min=2ms max=4ms mean=3.35799ms stddev=0.183248
> ok 35 Remove random-search 16384 keys: min=5ms max=8ms mean=6.86078ms stddev=0.261931
> ok 36 Remove async 16384 keys: min=0ms max=0ms mean=0.0302384ms stddev=0.0173892
> # Totals: pass:36 fail:0 xfail:0 xpass:0 skip:0 error:0

>From the output it's visible that the current simplified approach with
linked-list of MKTs scales quite fine even for thousands of keys.
And that also means that the majority of the time for delete is eaten by
synchronize_rcu() [which I can confirm separately by tracing].

Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
---
tools/testing/selftests/net/tcp_ao/Makefile | 5 +-
tools/testing/selftests/net/tcp_ao/bench-lookups.c | 358 +++++++++++++++++++++
2 files changed, 362 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/net/tcp_ao/Makefile b/tools/testing/selftests/net/tcp_ao/Makefile
index ee2f1a17e805..f0b218b99506 100644
--- a/tools/testing/selftests/net/tcp_ao/Makefile
+++ b/tools/testing/selftests/net/tcp_ao/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
-TEST_BOTH_AF := connect
+TEST_BOTH_AF := bench-lookups
+TEST_BOTH_AF += connect
TEST_BOTH_AF += connect-deny
TEST_BOTH_AF += icmps-accept icmps-discard
TEST_BOTH_AF += setsockopt-closed
@@ -49,3 +50,5 @@ $(OUTPUT)/%_ipv6: %.c

$(OUTPUT)/icmps-accept_ipv4: CFLAGS+= -DTEST_ICMPS_ACCEPT
$(OUTPUT)/icmps-accept_ipv6: CFLAGS+= -DTEST_ICMPS_ACCEPT
+$(OUTPUT)/bench-lookups_ipv4: LDFLAGS+= -lm
+$(OUTPUT)/bench-lookups_ipv6: LDFLAGS+= -lm
diff --git a/tools/testing/selftests/net/tcp_ao/bench-lookups.c b/tools/testing/selftests/net/tcp_ao/bench-lookups.c
new file mode 100644
index 000000000000..7be8a7d9308c
--- /dev/null
+++ b/tools/testing/selftests/net/tcp_ao/bench-lookups.c
@@ -0,0 +1,358 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Author: Dmitry Safonov <dima@xxxxxxxxxx> */
+#include <arpa/inet.h>
+#include <inttypes.h>
+#include <math.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+
+#include "../../../../include/linux/bits.h"
+#include "../../../../include/linux/kernel.h"
+#include "aolib.h"
+
+#define BENCH_NR_ITERS 100 /* number of times to run gathering statistics */
+
+static void gen_test_ips(union tcp_addr *ips, size_t ips_nr, bool use_rand)
+{
+ union tcp_addr net = {};
+ size_t i, j;
+
+ if (inet_pton(TEST_FAMILY, TEST_NETWORK, &net) != 1)
+ test_error("Can't convert ip address %s", TEST_NETWORK);
+
+ if (!use_rand) {
+ for (i = 0; i < ips_nr; i++)
+ ips[i] = gen_tcp_addr(net, 2 * i + 1);
+ return;
+ }
+ for (i = 0; i < ips_nr; i++) {
+ size_t r = (size_t)random() | 0x1;
+
+ ips[i] = gen_tcp_addr(net, r);
+
+ for (j = i - 1; j > 0 && i > 0; j--) {
+ if (!memcmp(&ips[i], &ips[j], sizeof(union tcp_addr))) {
+ i--; /* collision */
+ break;
+ }
+ }
+ }
+}
+
+static void test_add_routes(union tcp_addr *ips, size_t ips_nr)
+{
+ size_t i;
+
+ for (i = 0; i < ips_nr; i++) {
+ union tcp_addr *p = (union tcp_addr *)&ips[i];
+
+ if (ip_route_add(veth_name, TEST_FAMILY, this_ip_addr, *p))
+ test_error("Failed to add route");
+ }
+}
+
+static void server_apply_keys(int lsk, union tcp_addr *ips, size_t ips_nr)
+{
+ size_t i;
+
+ for (i = 0; i < ips_nr; i++) {
+ union tcp_addr *p = (union tcp_addr *)&ips[i];
+
+ if (test_add_key(lsk, DEFAULT_TEST_PASSWORD, *p, -1, 100, 100))
+ test_error("setsockopt(TCP_AO)");
+ }
+}
+
+static const size_t nr_keys[] = { 512, 1024, 2048, 4096, 8192 };
+static union tcp_addr *test_ips;
+
+struct bench_stats {
+ uint64_t min;
+ uint64_t max;
+ uint64_t nr;
+ double mean;
+ double s2;
+};
+
+static struct bench_tests {
+ struct bench_stats delete_last_key;
+ struct bench_stats add_key;
+ struct bench_stats delete_rand_key;
+ struct bench_stats connect_last_key;
+ struct bench_stats connect_rand_key;
+ struct bench_stats delete_async;
+} bench_results[ARRAY_SIZE(nr_keys)];
+
+#define NSEC_PER_SEC 1000000000ULL
+
+static void measure_call(struct bench_stats *st,
+ void (*f)(int, void *), int sk, void *arg)
+{
+ struct timespec start = {}, end = {};
+ double delta;
+ uint64_t nsec;
+
+ if (clock_gettime(CLOCK_MONOTONIC, &start))
+ test_error("clock_gettime()");
+
+ f(sk, arg);
+
+ if (clock_gettime(CLOCK_MONOTONIC, &end))
+ test_error("clock_gettime()");
+
+ nsec = (end.tv_sec - start.tv_sec) * NSEC_PER_SEC;
+ if (end.tv_nsec >= start.tv_nsec)
+ nsec += end.tv_nsec - start.tv_nsec;
+ else
+ nsec -= start.tv_nsec - end.tv_nsec;
+
+ if (st->nr == 0) {
+ st->min = st->max = nsec;
+ } else {
+ if (st->min > nsec)
+ st->min = nsec;
+ if (st->max < nsec)
+ st->max = nsec;
+ }
+
+ /* Welford-Knuth algorithm */
+ st->nr++;
+ delta = (double)nsec - st->mean;
+ st->mean += delta / st->nr;
+ st->s2 += delta * ((double)nsec - st->mean);
+}
+
+static void delete_mkt(int sk, void *arg)
+{
+ struct tcp_ao_del *ao = arg;
+
+ if (setsockopt(sk, IPPROTO_TCP, TCP_AO_DEL_KEY, ao, sizeof(*ao)))
+ test_error("setsockopt(TCP_AO_DEL_KEY)");
+}
+
+static void add_back_mkt(int sk, void *arg)
+{
+ union tcp_addr *p = arg;
+
+ if (test_add_key(sk, DEFAULT_TEST_PASSWORD, *p, -1, 100, 100))
+ test_error("setsockopt(TCP_AO)");
+}
+
+static void bench_delete(int lsk, struct bench_stats *add,
+ struct bench_stats *del,
+ union tcp_addr *ips, size_t ips_nr,
+ bool rand_order, bool async)
+{
+ struct tcp_ao_del ao_del = {};
+ union tcp_addr *p;
+ size_t i;
+
+ ao_del.sndid = 100;
+ ao_del.rcvid = 100;
+ ao_del.del_async = !!async;
+ ao_del.prefix = DEFAULT_TEST_PREFIX;
+
+ /* Remove the first added */
+ p = (union tcp_addr *)&ips[0];
+ tcp_addr_to_sockaddr_in(&ao_del.addr, p, 0);
+
+ for (i = 0; i < BENCH_NR_ITERS; i++) {
+ measure_call(del, delete_mkt, lsk, (void *)&ao_del);
+
+ /* Restore it back */
+ measure_call(add, add_back_mkt, lsk, (void *)p);
+
+ /*
+ * Slowest for FILO-linked-list:
+ * on (i) iteration removing ips[i] element. When it gets
+ * added to the list back - it becomes first to fetch, so
+ * on (i + 1) iteration go to ips[i + 1] element.
+ */
+ if (rand_order)
+ p = (union tcp_addr *)&ips[rand() % ips_nr];
+ else
+ p = (union tcp_addr *)&ips[i % ips_nr];
+ tcp_addr_to_sockaddr_in(&ao_del.addr, p, 0);
+ }
+}
+
+static void bench_connect_srv(int lsk, union tcp_addr *ips, size_t ips_nr)
+{
+ size_t i;
+
+ for (i = 0; i < BENCH_NR_ITERS; i++) {
+ int sk;
+
+ synchronize_threads();
+
+ if (test_wait_fd(lsk, TEST_TIMEOUT_SEC, 0))
+ test_error("test_wait_fd()");
+
+ sk = accept(lsk, NULL, NULL);
+ if (sk < 0)
+ test_error("accept()");
+
+ close(sk);
+ }
+}
+
+static void test_print_stats(const char *desc, size_t nr, struct bench_stats *bs)
+{
+ test_ok("%-20s\t%zu keys: min=%" PRIu64 "ms max=%" PRIu64 "ms mean=%gms stddev=%g",
+ desc, nr, bs->min / 1000000, bs->max / 1000000,
+ bs->mean / 1000000, sqrt((bs->mean / 1000000) / bs->nr));
+}
+
+static void *server_fn(void *arg)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(nr_keys); i++) {
+ struct bench_tests *bt = &bench_results[i];
+ int lsk;
+
+ test_ips = malloc(nr_keys[i] * sizeof(union tcp_addr));
+ if (!test_ips)
+ test_error("malloc()");
+
+ lsk = test_listen_socket(this_ip_addr, test_server_port + i, 1);
+
+ gen_test_ips(test_ips, nr_keys[i], false);
+ test_add_routes(test_ips, nr_keys[i]);
+ test_set_optmem(KERNEL_TCP_AO_KEY_SZ_ROUND_UP * nr_keys[i]);
+ server_apply_keys(lsk, test_ips, nr_keys[i]);
+
+ synchronize_threads();
+ bench_connect_srv(lsk, test_ips, nr_keys[i]);
+ bench_connect_srv(lsk, test_ips, nr_keys[i]);
+
+ /* The worst case for FILO-list */
+ bench_delete(lsk, &bt->add_key, &bt->delete_last_key,
+ test_ips, nr_keys[i], false, false);
+ test_print_stats("Add a new key",
+ nr_keys[i], &bt->add_key);
+ test_print_stats("Delete: worst case",
+ nr_keys[i], &bt->delete_last_key);
+
+ bench_delete(lsk, &bt->add_key, &bt->delete_rand_key,
+ test_ips, nr_keys[i], true, false);
+ test_print_stats("Delete: random-search",
+ nr_keys[i], &bt->delete_rand_key);
+
+ bench_delete(lsk, &bt->add_key, &bt->delete_async,
+ test_ips, nr_keys[i], false, true);
+ test_print_stats("Delete: async", nr_keys[i], &bt->delete_async);
+
+ free(test_ips);
+ close(lsk);
+ }
+
+ return NULL;
+}
+
+static void connect_client(int sk, void *arg)
+{
+ size_t *p = arg;
+
+ if (test_connect_socket(sk, this_ip_dest, test_server_port + *p) <= 0)
+ test_error("failed to connect()");
+}
+
+static void client_addr_setup(int sk, union tcp_addr taddr)
+{
+#ifdef IPV6_TEST
+ struct sockaddr_in6 addr = {
+ .sin6_family = AF_INET6,
+ .sin6_port = 0,
+ .sin6_addr = taddr.a6,
+ };
+#else
+ struct sockaddr_in addr = {
+ .sin_family = AF_INET,
+ .sin_port = 0,
+ .sin_addr = taddr.a4,
+ };
+#endif
+ int ret;
+
+ ret = ip_addr_add(veth_name, TEST_FAMILY, taddr, TEST_PREFIX);
+ if (ret && ret != -EEXIST)
+ test_error("Failed to add ip address");
+ ret = ip_route_add(veth_name, TEST_FAMILY, taddr, this_ip_dest);
+ if (ret && ret != -EEXIST)
+ test_error("Failed to add route");
+
+ if (bind(sk, &addr, sizeof(addr)))
+ test_error("bind()");
+}
+
+static void bench_connect_client(size_t port_off, struct bench_tests *bt,
+ union tcp_addr *ips, size_t ips_nr, bool rand_order)
+{
+ struct bench_stats *con;
+ union tcp_addr *p;
+ size_t i;
+
+ if (rand_order)
+ con = &bt->connect_rand_key;
+ else
+ con = &bt->connect_last_key;
+
+ p = (union tcp_addr *)&ips[0];
+
+ for (i = 0; i < BENCH_NR_ITERS; i++) {
+ int sk = socket(test_family, SOCK_STREAM, IPPROTO_TCP);
+
+ if (sk < 0)
+ test_error("socket()");
+
+ client_addr_setup(sk, *p);
+ if (test_add_key(sk, DEFAULT_TEST_PASSWORD, this_ip_dest,
+ -1, 100, 100))
+ test_error("setsockopt(TCP_AO_ADD_KEY)");
+
+ synchronize_threads();
+
+ measure_call(con, connect_client, sk, (void *)&port_off);
+
+ close(sk);
+
+ /*
+ * Slowest for FILO-linked-list:
+ * on (i) iteration removing ips[i] element. When it gets
+ * added to the list back - it becomes first to fetch, so
+ * on (i + 1) iteration go to ips[i + 1] element.
+ */
+ if (rand_order)
+ p = (union tcp_addr *)&ips[rand() % ips_nr];
+ else
+ p = (union tcp_addr *)&ips[i % ips_nr];
+ }
+}
+
+static void *client_fn(void *arg)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(nr_keys); i++) {
+ struct bench_tests *bt = &bench_results[i];
+
+ synchronize_threads();
+ bench_connect_client(i, bt, test_ips, nr_keys[i], false);
+ test_print_stats("Connect: worst case",
+ nr_keys[i], &bt->connect_last_key);
+
+ bench_connect_client(i, bt, test_ips, nr_keys[i], false);
+ test_print_stats("Connect: random-search",
+ nr_keys[i], &bt->connect_last_key);
+ }
+ synchronize_threads();
+ return NULL;
+}
+
+int main(int argc, char *argv[])
+{
+ test_init(30, server_fn, client_fn);
+ return 0;
+}

--
2.43.0