[LTP] [PATCH v1] Add epoll_wait07 test

[Richard Palethorpe]

Hello,

Andrea Cervesato via ltp <ltp@lists.linux.it> writes:

> This test verifies EPOLLONESHOT functionality.
>
> Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
> ---
>  .../kernel/syscalls/epoll_wait/.gitignore     |  1 +
>  .../kernel/syscalls/epoll_wait/epoll_wait07.c | 86 +++++++++++++++++++
>  2 files changed, 87 insertions(+)
>  create mode 100644 testcases/kernel/syscalls/epoll_wait/epoll_wait07.c
>
> diff --git a/testcases/kernel/syscalls/epoll_wait/.gitignore b/testcases/kernel/syscalls/epoll_wait/.gitignore
> index 8c5ed7c5c..66ac18ae2 100644
> --- a/testcases/kernel/syscalls/epoll_wait/.gitignore
> +++ b/testcases/kernel/syscalls/epoll_wait/.gitignore
> @@ -4,3 +4,4 @@ epoll_wait03
>  epoll_wait04
>  epoll_wait05
>  epoll_wait06
> +epoll_wait07
> diff --git a/testcases/kernel/syscalls/epoll_wait/epoll_wait07.c b/testcases/kernel/syscalls/epoll_wait/epoll_wait07.c
> new file mode 100644
> index 000000000..760ab6c10
> --- /dev/null
> +++ b/testcases/kernel/syscalls/epoll_wait/epoll_wait07.c
> @@ -0,0 +1,86 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2022 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
> + */
> +
> +/*\
> + * [Description]
> + *
> + * Verify that EPOLLONESHOT is correctly handled by epoll_wait.
> + * We open a channel, write on it multiple times and we verify that EPOLLOUT
> + * has been received only once.

Without EPOLLONESHOT or EPOLLET, EPOLLOUT will fire constantly on a pipe
who's buffer is not full. Writing to it will have no effect unless you
listen on the other end for EPOLLIN.

So in this test you don't need to write to the pipe unless I am
mistaken.

> + */
> +
> +#include <poll.h>
> +#include <sys/epoll.h>
> +#include "tst_test.h"
> +
> +#define WRITE_SIZE 2048
> +
> +static int fds[2];
> +static int epfd;
> +
> +static void cleanup(void)
> +{
> +	if (epfd > 0)
> +		SAFE_CLOSE(epfd);
> +
> +	if (fds[0] > 0)
> +		SAFE_CLOSE(fds[0]);
> +
> +	if (fds[1] > 0)
> +		SAFE_CLOSE(fds[1]);
> +}
> +
> +static void run(void)
> +{
> +	int res;
> +	char buff[WRITE_SIZE];
> +	struct epoll_event evt_receive;
> +	struct epoll_event evt_request;
> +
> +	SAFE_PIPE(fds);
> +
> +	evt_request.events = EPOLLOUT | EPOLLONESHOT;
> +	evt_request.data.fd = fds[1];
> +
> +	epfd = epoll_create(2);
> +	if (epfd == -1)
> +		tst_brk(TBROK | TERRNO, "fail to create epoll
> instance");

Same as other test, please use the SAFE_EPOLL_* functions I just merged.

-- 
Thank you,
Richard.