From 538aaf9b2383701094a47797b4554c6a21c83eed Mon Sep 17 00:00:00 2001 From: Joanne Koong Date: Thu, 19 May 2022 17:18:34 -0700 Subject: [PATCH] selftests: Add test for timing a bind request to a port with a populated bhash entry This test populates the bhash table for a given port with MAX_THREADS * MAX_CONNECTIONS sockets, and then times how long a bind request on the port takes. When populating the bhash table, we create the sockets and then bind the sockets to the same address and port (SO_REUSEADDR and SO_REUSEPORT are set). When timing how long a bind on the port takes, we bind on a different address without SO_REUSEPORT set. We do not set SO_REUSEPORT because we are interested in the case where the bind request does not go through the tb->fastreuseport path, which is fragile (eg tb->fastreuseport path does not work if binding with a different uid). To run the test locally, I did: * ulimit -n 65535000 * ip addr add 2001:0db8:0:f101::1 dev eth0 * ./bind_bhash_test 443 Signed-off-by: Joanne Koong Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 2 + tools/testing/selftests/net/bind_bhash_test.c | 119 ++++++++++++++++++ 3 files changed, 122 insertions(+) create mode 100644 tools/testing/selftests/net/bind_bhash_test.c diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index 21a411b04890..735423136bc4 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -36,3 +36,4 @@ gro ioam6_parser toeplitz cmsg_sender +bind_bhash_test diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 7ea54af55490..464df13831f2 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -59,6 +59,7 @@ TEST_GEN_FILES += toeplitz TEST_GEN_FILES += cmsg_sender TEST_GEN_FILES += stress_reuseport_listen TEST_PROGS += test_vxlan_vnifiltering.sh +TEST_GEN_FILES += bind_bhash_test TEST_FILES := settings @@ -69,4 +70,5 @@ include bpf/Makefile $(OUTPUT)/reuseport_bpf_numa: LDLIBS += -lnuma $(OUTPUT)/tcp_mmap: LDLIBS += -lpthread +$(OUTPUT)/bind_bhash_test: LDLIBS += -lpthread $(OUTPUT)/tcp_inq: LDLIBS += -lpthread diff --git a/tools/testing/selftests/net/bind_bhash_test.c b/tools/testing/selftests/net/bind_bhash_test.c new file mode 100644 index 000000000000..252e73754e76 --- /dev/null +++ b/tools/testing/selftests/net/bind_bhash_test.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This times how long it takes to bind to a port when the port already + * has multiple sockets in its bhash table. + * + * In the setup(), we populate the port's bhash table with + * MAX_THREADS * MAX_CONNECTIONS number of entries. + */ + +#include +#include +#include +#include + +#define MAX_THREADS 600 +#define MAX_CONNECTIONS 40 + +static const char *bind_addr = "::1"; +static const char *port; + +static int fd_array[MAX_THREADS][MAX_CONNECTIONS]; + +static int bind_socket(int opt, const char *addr) +{ + struct addrinfo *res, hint = {}; + int sock_fd, reuse = 1, err; + + sock_fd = socket(AF_INET6, SOCK_STREAM, 0); + if (sock_fd < 0) { + perror("socket fd err"); + return -1; + } + + hint.ai_family = AF_INET6; + hint.ai_socktype = SOCK_STREAM; + + err = getaddrinfo(addr, port, &hint, &res); + if (err) { + perror("getaddrinfo failed"); + return -1; + } + + if (opt) { + err = setsockopt(sock_fd, SOL_SOCKET, opt, &reuse, sizeof(reuse)); + if (err) { + perror("setsockopt failed"); + return -1; + } + } + + err = bind(sock_fd, res->ai_addr, res->ai_addrlen); + if (err) { + perror("failed to bind to port"); + return -1; + } + + return sock_fd; +} + +static void *setup(void *arg) +{ + int sock_fd, i; + int *array = (int *)arg; + + for (i = 0; i < MAX_CONNECTIONS; i++) { + sock_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, bind_addr); + if (sock_fd < 0) + return NULL; + array[i] = sock_fd; + } + + return NULL; +} + +int main(int argc, const char *argv[]) +{ + int listener_fd, sock_fd, i, j; + pthread_t tid[MAX_THREADS]; + clock_t begin, end; + + if (argc != 2) { + printf("Usage: listener \n"); + return -1; + } + + port = argv[1]; + + listener_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, bind_addr); + if (listen(listener_fd, 100) < 0) { + perror("listen failed"); + return -1; + } + + /* Set up threads to populate the bhash table entry for the port */ + for (i = 0; i < MAX_THREADS; i++) + pthread_create(&tid[i], NULL, setup, fd_array[i]); + + for (i = 0; i < MAX_THREADS; i++) + pthread_join(tid[i], NULL); + + begin = clock(); + + /* Bind to the same port on a different address */ + sock_fd = bind_socket(0, "2001:0db8:0:f101::1"); + + end = clock(); + + printf("time spent = %f\n", (double)(end - begin) / CLOCKS_PER_SEC); + + /* clean up */ + close(sock_fd); + close(listener_fd); + for (i = 0; i < MAX_THREADS; i++) { + for (j = 0; i < MAX_THREADS; i++) + close(fd_array[i][j]); + } + + return 0; +}