The test verifies that when there is active TCP connection, the memory.stat.sock and memory.current values are close.

Signed-off-by: Mike Rapoport rppt@linux.vnet.ibm.com Acked-by: Roman Gushchin guro@fb.com --- v3 changes: * added changelog

v2 changes: * bumped error percentage for comparing memory.current with memory.stat.sock * added checks that memory.stat.sock == 0 and memory.current >= 0 after TCP server exits * simplified error handling

tools/testing/selftests/cgroup/test_memcontrol.c | 193 +++++++++++++++++++++++ 1 file changed, 193 insertions(+)

diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c index beae06c9c899..cf0bddc9d271 100644 --- a/tools/testing/selftests/cgroup/test_memcontrol.c +++ b/tools/testing/selftests/cgroup/test_memcontrol.c @@ -9,6 +9,12 @@ #include <sys/stat.h> #include <sys/types.h> #include <unistd.h> +#include <sys/socket.h> +#include <sys/wait.h> +#include <arpa/inet.h> +#include <netinet/in.h> +#include <netdb.h> +#include <errno.h>

#include "../kselftest.h" #include "cgroup_util.h" @@ -772,6 +778,192 @@ static int test_memcg_oom_events(const char *root) return ret; }

+struct tcp_server_args { + unsigned short port; + int ctl[2]; +}; + +static int tcp_server(const char *cgroup, void *arg) +{ + struct tcp_server_args *srv_args = arg; + struct sockaddr_in6 saddr = { 0 }; + socklen_t slen = sizeof(saddr); + int sk, client_sk, ctl_fd, yes = 1, ret = -1; + + close(srv_args->ctl[0]); + ctl_fd = srv_args->ctl[1]; + + saddr.sin6_family = AF_INET6; + saddr.sin6_addr = in6addr_any; + saddr.sin6_port = htons(srv_args->port); + + sk = socket(AF_INET6, SOCK_STREAM, 0); + if (sk < 0) + return ret; + + if (setsockopt(sk, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) + goto cleanup; + + if (bind(sk, (struct sockaddr *)&saddr, slen)) { + write(ctl_fd, &errno, sizeof(errno)); + goto cleanup; + } + + if (listen(sk, 1)) + goto cleanup; + + ret = 0; + if (write(ctl_fd, &ret, sizeof(ret)) != sizeof(ret)) { + ret = -1; + goto cleanup; + } + + client_sk = accept(sk, NULL, NULL); + if (client_sk < 0) + goto cleanup; + + ret = -1; + for (;;) { + uint8_t buf[0x100000]; + + if (write(client_sk, buf, sizeof(buf)) <= 0) { + if (errno == ECONNRESET) + ret = 0; + break; + } + } + + close(client_sk); + +cleanup: + close(sk); + return ret; +} + +static int tcp_client(const char *cgroup, unsigned short port) +{ + const char server[] = "localhost"; + struct addrinfo *ai; + char servport[6]; + int retries = 0x10; /* nice round number */ + int sk, ret; + + snprintf(servport, sizeof(servport), "%hd", port); + ret = getaddrinfo(server, servport, NULL, &ai); + if (ret) + return ret; + + sk = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); + if (sk < 0) + goto free_ainfo; + + ret = connect(sk, ai->ai_addr, ai->ai_addrlen); + if (ret < 0) + goto close_sk; + + ret = KSFT_FAIL; + while (retries--) { + uint8_t buf[0x100000]; + long current, sock; + + if (read(sk, buf, sizeof(buf)) <= 0) + goto close_sk; + + current = cg_read_long(cgroup, "memory.current"); + sock = cg_read_key_long(cgroup, "memory.stat", "sock "); + + if (current < 0 || sock < 0) + goto close_sk; + + if (current < sock) + goto close_sk; + + if (values_close(current, sock, 10)) { + ret = KSFT_PASS; + break; + } + } + +close_sk: + close(sk); +free_ainfo: + freeaddrinfo(ai); + return ret; +} + +/* + * This test checks socket memory accounting. + * The test forks a TCP server listens on a random port between 1000 + * and 61000. Once it gets a client connection, it starts writing to + * its socket. + * The TCP client interleaves reads from the socket with check whether + * memory.current and memory.stat.sock are similar. + */ +static int test_memcg_sock(const char *root) +{ + int bind_retries = 5, ret = KSFT_FAIL, pid, err; + unsigned short port; + char *memcg; + + memcg = cg_name(root, "memcg_test"); + if (!memcg) + goto cleanup; + + if (cg_create(memcg)) + goto cleanup; + + while (bind_retries--) { + struct tcp_server_args args; + + if (pipe(args.ctl)) + goto cleanup; + + port = args.port = 1000 + rand() % 60000; + + pid = cg_run_nowait(memcg, tcp_server, &args); + if (pid < 0) + goto cleanup; + + close(args.ctl[1]); + if (read(args.ctl[0], &err, sizeof(err)) != sizeof(err)) + goto cleanup; + close(args.ctl[0]); + + if (!err) + break; + if (err != EADDRINUSE) + goto cleanup; + + waitpid(pid, NULL, 0); + } + + if (err == EADDRINUSE) { + ret = KSFT_SKIP; + goto cleanup; + } + + if (tcp_client(memcg, port) != KSFT_PASS) + goto cleanup; + + waitpid(pid, &err, 0); + if (WEXITSTATUS(err)) + goto cleanup; + + if (cg_read_long(memcg, "memory.current") < 0) + goto cleanup; + + if (cg_read_key_long(memcg, "memory.stat", "sock ")) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + cg_destroy(memcg); + free(memcg); + + return ret; +} + #define T(x) { x, #x } struct memcg_test { int (*fn)(const char *root); @@ -785,6 +977,7 @@ struct memcg_test { T(test_memcg_max), T(test_memcg_oom_events), T(test_memcg_swap_max), + T(test_memcg_sock), }; #undef T