Re: [PATCH v3] selftests: cgroup/memcontrol: add basic test for socket accounting

[Mike Rapoport <rppt@linux.vnet.ibm.com>]

Hi,

Are there any updates on this?

On Tue, May 22, 2018 at 11:06:05PM +0300, Mike Rapoport wrote:
> 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
> 
> -- 
> 2.7.4
> 

-- 
Sincerely yours,
Mike.