[dpdk-dev] [PATCH v2 1/2] telemetry: fix missing check for thread creation

[David Marchand]

On Mon, Apr 12, 2021 at 2:32 AM Min Hu (Connor) <humin29 at huawei.com> wrote:
>
> From: Chengwen Feng <fengchengwen at huawei.com>
>
> Add result check and message print out for thread creation after
> failure.

Ah, I was looking at this code too, while looking at your other series :-).


>
> Fixes: b80fe1805eee ("telemetry: introduce backward compatibility")
> Cc: stable at dpdk.org
>
> Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
> Signed-off-by: Min Hu (Connor) <humin29 at huawei.com>
> ---
>  lib/librte_telemetry/telemetry.c        | 28 +++++++++++++++++++++++++---
>  lib/librte_telemetry/telemetry_legacy.c | 10 ++++++++--
>  2 files changed, 33 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_telemetry/telemetry.c b/lib/librte_telemetry/telemetry.c
> index 7e08afd..3f1a4c4 100644
> --- a/lib/librte_telemetry/telemetry.c
> +++ b/lib/librte_telemetry/telemetry.c
> @@ -350,6 +350,7 @@ socket_listener(void *socket)
>  {
>         while (1) {
>                 pthread_t th;
> +               int rc;
>                 struct socket *s = (struct socket *)socket;
>                 int s_accepted = accept(s->sock, NULL, NULL);
>                 if (s_accepted < 0) {
> @@ -366,7 +367,14 @@ socket_listener(void *socket)
>                         __atomic_add_fetch(s->num_clients, 1,
>                                         __ATOMIC_RELAXED);
>                 }
> -               pthread_create(&th, NULL, s->fn, (void *)(uintptr_t)s_accepted);
> +               rc = pthread_create(&th, NULL, s->fn,
> +                                   (void *)(uintptr_t)s_accepted);
> +               if (rc) {

Either you use this rc variable (adding strerror(rc) in the log
message below) or you can remove it.
This comment applies to others updates below.


> +                       TMTY_LOG(ERR, "Error with create thread, telemetry thread quitting\n");
> +                       close(s_accepted);
> +                       return NULL;
> +               }
> +
>                 pthread_detach(th);
>         }
>         return NULL;
> @@ -425,6 +433,7 @@ static int
>  telemetry_legacy_init(void)
>  {
>         pthread_t t_old;
> +       int rc;
>
>         if (num_legacy_callbacks == 1) {
>                 TMTY_LOG(WARNING, "No legacy callbacks, legacy socket not created\n");
> @@ -440,7 +449,13 @@ Fixes: 3b3757bda3c3 ("net/ice: get VF hardware index in DCF")
(void)
>         v1_socket.sock = create_socket(v1_socket.path);
>         if (v1_socket.sock < 0)
>                 return -1;
> -       pthread_create(&t_old, NULL, socket_listener, &v1_socket);
> +       rc = pthread_create(&t_old, NULL, socket_listener, &v1_socket);
> +       if (rc) {
> +               TMTY_LOG(ERR, "Error with create thread\n");
> +               unlink_sockets();

Before this patch, v2 mode could be working fine with v1 ko.
I think it was intended since telemetry_legacy_init return value is
not checked and unlink_sockets() checks whether the v1 and v2 sockets
have been created.

Plus, in this error handling, the v1 socket fd is left open.

How about:

+       ret = pthread_create(&t_old, NULL, socket_listener, &v1_socket);
+       if (ret != 0) {
+               TMTY_LOG(DEBUG, "Failed to create handler for legacy
socket: %s\n",
+                       strerror(ret));
+               close(v1_socket.sock);
+               v1_socket.sock = -1;
+               if (v1_socket.path[0]) {
+                       unlink(v1_socket.path);
+                       v1_socket.path[0] = '\0';
+               }
+               return -1;
+       }


> +               return -1;
> +       }
> +
>         pthread_setaffinity_np(t_old, sizeof(*thread_cpuset), thread_cpuset);
>
>         TMTY_LOG(DEBUG, "Legacy telemetry socket initialized ok\n");
> @@ -451,6 +466,7 @@ static int
>  telemetry_v2_init(void)
>  {
>         pthread_t t_new;
> +       int rc;
>
>         v2_socket.num_clients = &v2_clients;
>         rte_telemetry_register_cmd("/", list_commands,
> @@ -469,7 +485,13 @@ telemetry_v2_init(void)
>         v2_socket.sock = create_socket(v2_socket.path);
>         if (v2_socket.sock < 0)
>                 return -1;
> -       pthread_create(&t_new, NULL, socket_listener, &v2_socket);
> +       rc = pthread_create(&t_new, NULL, socket_listener, &v2_socket);
> +       if (rc) {
> +               TMTY_LOG(ERR, "Error with create thread\n");
> +               unlink_sockets();
> +               return -1;
> +       }
> +

Missing a close on v2 socket,


>         pthread_setaffinity_np(t_new, sizeof(*thread_cpuset), thread_cpuset);
>         atexit(unlink_sockets);
>
> diff --git a/lib/librte_telemetry/telemetry_legacy.c b/lib/librte_telemetry/telemetry_legacy.c
> index 5e9af37..9587bfe 100644
> --- a/lib/librte_telemetry/telemetry_legacy.c
> +++ b/lib/librte_telemetry/telemetry_legacy.c
> @@ -83,6 +83,7 @@ register_client(const char *cmd __rte_unused, const char *params,
>         pthread_t th;
>         char data[BUF_SIZE];
>         int fd;
> +       int rc;
>         struct sockaddr_un addrs;
>  #endif /* !RTE_EXEC_ENV_WINDOWS */
>
> @@ -112,8 +113,13 @@ register_client(const char *cmd __rte_unused, const char *params,
>                 close(fd);
>                 return -1;
>         }
> -       pthread_create(&th, NULL, &legacy_client_handler,
> -                       (void *)(uintptr_t)fd);
> +       rc = pthread_create(&th, NULL, &legacy_client_handler,
> +                               (void *)(uintptr_t)fd);
> +       if (rc) {
> +               fprintf(stderr, "Failed to create thread\n");
> +               close(fd);
> +               return -1;
> +       }
>  #endif /* !RTE_EXEC_ENV_WINDOWS */
>         return 0;
>  }
> --
> 2.7.4
>



-- 
David Marchand