diff mbox series

[v7,3/5] telemetry: use unique socket paths for in-memory mode

Message ID 20211008171852.736387-4-bruce.richardson@intel.com (mailing list archive)
State Superseded, archived
Delegated to: David Marchand
Headers
Series improve telemetry support with in-memory mode |

Checks

Context Check Description
ci/checkpatch warning coding style issues

Commit Message

Bruce Richardson Oct. 8, 2021, 5:18 p.m. UTC 
  When running in in-memory mode, multiple processes can use the same
runtime dir, leading to conflicts with the telemetry sockets in that
directory. We can resolve this by appending a suffix to each socket
beyond the first, with the suffix being an increasing counter value.
Each process uses the first unused socket counter value.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/telemetry/telemetry.c | 45 +++++++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 16 deletions(-)

Comments

Power, Ciara Oct. 12, 2021, 3:37 p.m. UTC | #1 
Hi Bruce,

>-----Original Message-----
>From: Richardson, Bruce <bruce.richardson@intel.com>
>Sent: Friday 8 October 2021 18:19
>To: dev@dpdk.org
>Cc: Power, Ciara <ciara.power@intel.com>; David Marchand
><david.marchand@redhat.com>; Burakov, Anatoly
><anatoly.burakov@intel.com>; Kevin Traynor <ktraynor@redhat.com>;
>Richardson, Bruce <bruce.richardson@intel.com>
>Subject: [PATCH v7 3/5] telemetry: use unique socket paths for in-memory
>mode
>
>When running in in-memory mode, multiple processes can use the same
>runtime dir, leading to conflicts with the telemetry sockets in that directory.
>We can resolve this by appending a suffix to each socket beyond the first,
>with the suffix being an increasing counter value.
>Each process uses the first unused socket counter value.
>
>Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
>---
<snip>

Thanks,

Acked-by: Ciara Power <ciara.power@intel.com>
Bruce Richardson Oct. 12, 2021, 3:40 p.m. UTC | #2 
On Tue, Oct 12, 2021 at 04:37:07PM +0100, Power, Ciara wrote:
> Hi Bruce,
> 
> >-----Original Message-----
> >From: Richardson, Bruce <bruce.richardson@intel.com>
> >Sent: Friday 8 October 2021 18:19
> >To: dev@dpdk.org
> >Cc: Power, Ciara <ciara.power@intel.com>; David Marchand
> ><david.marchand@redhat.com>; Burakov, Anatoly
> ><anatoly.burakov@intel.com>; Kevin Traynor <ktraynor@redhat.com>;
> >Richardson, Bruce <bruce.richardson@intel.com>
> >Subject: [PATCH v7 3/5] telemetry: use unique socket paths for in-memory
> >mode
> >
> >When running in in-memory mode, multiple processes can use the same
> >runtime dir, leading to conflicts with the telemetry sockets in that directory.
> >We can resolve this by appending a suffix to each socket beyond the first,
> >with the suffix being an increasing counter value.
> >Each process uses the first unused socket counter value.
> >
> >Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> >---
> <snip>
> 
> Thanks,
> 
> Acked-by: Ciara Power <ciara.power@intel.com>

Thanks.

I'm actually in two minds as to whether to this patch should be merged with
the previous one. It was already reviewed and acked as a bugfix, but this
patch also affects a lot of the same areas of code. What do you think?

/Bruce
Power, Ciara Oct. 12, 2021, 3:47 p.m. UTC | #3 
>-----Original Message-----
>From: Richardson, Bruce <bruce.richardson@intel.com>
>Sent: Tuesday 12 October 2021 16:41
>To: Power, Ciara <ciara.power@intel.com>
>Cc: dev@dpdk.org; David Marchand <david.marchand@redhat.com>;
>Burakov, Anatoly <anatoly.burakov@intel.com>; Kevin Traynor
><ktraynor@redhat.com>
>Subject: Re: [PATCH v7 3/5] telemetry: use unique socket paths for in-
>memory mode
>
>On Tue, Oct 12, 2021 at 04:37:07PM +0100, Power, Ciara wrote:
>> Hi Bruce,
>>
>> >-----Original Message-----
>> >From: Richardson, Bruce <bruce.richardson@intel.com>
>> >Sent: Friday 8 October 2021 18:19
>> >To: dev@dpdk.org
>> >Cc: Power, Ciara <ciara.power@intel.com>; David Marchand
>> ><david.marchand@redhat.com>; Burakov, Anatoly
>> ><anatoly.burakov@intel.com>; Kevin Traynor <ktraynor@redhat.com>;
>> >Richardson, Bruce <bruce.richardson@intel.com>
>> >Subject: [PATCH v7 3/5] telemetry: use unique socket paths for
>> >in-memory mode
>> >
>> >When running in in-memory mode, multiple processes can use the same
>> >runtime dir, leading to conflicts with the telemetry sockets in that
>directory.
>> >We can resolve this by appending a suffix to each socket beyond the
>> >first, with the suffix being an increasing counter value.
>> >Each process uses the first unused socket counter value.
>> >
>> >Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
>> >---
>> <snip>
>>
>> Thanks,
>>
>> Acked-by: Ciara Power <ciara.power@intel.com>
>
>Thanks.
>
>I'm actually in two minds as to whether to this patch should be merged with
>the previous one. It was already reviewed and acked as a bugfix, but this
>patch also affects a lot of the same areas of code. What do you think?
>
>/Bruce

Yes, I was actually wondering about that myself.
I think it would make more sense to merge them, rather than adding some code in patch 2 that then gets removed in patch 3.

Thanks,
Ciara
diff mbox series

Patch

diff --git a/lib/telemetry/telemetry.c b/lib/telemetry/telemetry.c
index 5d38e90bcc..a7483167d4 100644
--- a/lib/telemetry/telemetry.c
+++ b/lib/telemetry/telemetry.c
@@ -467,14 +467,14 @@  create_socket(char *path)
 		/* first check if we have a runtime dir */
 		if (stat(socket_dir, &st) < 0 || !S_ISDIR(st.st_mode)) {
 			TMTY_LOG(ERR, "Cannot access DPDK runtime directory: %s\n", socket_dir);
-			goto error;
+			close(sock);
+			return -ENOENT;
 		}
 
 		/* check if current socket is active */
 		if (connect(sock, (void *)&sun, sizeof(sun)) == 0) {
-			TMTY_LOG(ERR, "Error binding telemetry socket, path already in use\n");
-			TMTY_LOG(ERR, "Use '--file-prefix' to select a different socket path, or '--no-telemetry' to disable\n");
-			goto error;
+			close(sock);
+			return -EADDRINUSE;
 		}
 
 		/* socket is not active, delete and attempt rebind */
@@ -482,23 +482,20 @@  create_socket(char *path)
 		unlink(sun.sun_path);
 		if (bind(sock, (void *) &sun, sizeof(sun)) < 0) {
 			TMTY_LOG(ERR, "Error binding socket: %s\n", strerror(errno));
-			goto error;
+			close(sock);
+			return -errno; /* if unlink failed, this will be -EADDRINUSE as above */
 		}
 	}
 
 	if (listen(sock, 1) < 0) {
 		TMTY_LOG(ERR, "Error calling listen for socket: %s\n", strerror(errno));
 		unlink(sun.sun_path);
-		goto error;
+		close(sock);
+		return -errno;
 	}
 	TMTY_LOG(DEBUG, "Socket creation and binding ok\n");
 
 	return sock;
-
-error:
-	close(sock);
-	path[0] = 0;
-	return -1;
 }
 
 static void
@@ -531,8 +528,10 @@  telemetry_legacy_init(void)
 		return -1;
 	}
 	v1_socket.sock = create_socket(v1_socket.path);
-	if (v1_socket.sock < 0)
+	if (v1_socket.sock < 0) {
+		v1_socket.path[0] = '\0';
 		return -1;
+	}
 	rc = pthread_create(&t_old, NULL, socket_listener, &v1_socket);
 	if (rc != 0) {
 		TMTY_LOG(ERR, "Error with create legcay socket thread: %s\n",
@@ -553,7 +552,9 @@  telemetry_legacy_init(void)
 static int
 telemetry_v2_init(void)
 {
+	char spath[sizeof(v2_socket.path)];
 	pthread_t t_new;
+	short suffix = 0;
 	int rc;
 
 	v2_socket.num_clients = &v2_clients;
@@ -564,15 +565,27 @@  telemetry_v2_init(void)
 	rte_telemetry_register_cmd("/help", command_help,
 			"Returns help text for a command. Parameters: string command");
 	v2_socket.fn = client_handler;
-	if (strlcpy(v2_socket.path, get_socket_path(socket_dir, 2),
-			sizeof(v2_socket.path)) >= sizeof(v2_socket.path)) {
+	if (strlcpy(spath, get_socket_path(socket_dir, 2), sizeof(spath)) >= sizeof(spath)) {
 		TMTY_LOG(ERR, "Error with socket binding, path too long\n");
 		return -1;
 	}
+	memcpy(v2_socket.path, spath, sizeof(v2_socket.path));
 
 	v2_socket.sock = create_socket(v2_socket.path);
-	if (v2_socket.sock < 0)
-		return -1;
+	while (v2_socket.sock < 0) {
+		/* bail out on unexpected error, or suffix wrap-around */
+		if (v2_socket.sock != -EADDRINUSE || suffix < 0) {
+			v2_socket.path[0] = '\0'; /* clear socket path */
+			return -1;
+		}
+		/* add a suffix to the path if the basic version fails */
+		if (snprintf(v2_socket.path, sizeof(v2_socket.path), "%s:%d",
+				spath, ++suffix) >= (int)sizeof(v2_socket.path)) {
+			TMTY_LOG(ERR, "Error with socket binding, path too long\n");
+			return -1;
+		}
+		v2_socket.sock = create_socket(v2_socket.path);
+	}
 	rc = pthread_create(&t_new, NULL, socket_listener, &v2_socket);
 	if (rc != 0) {
 		TMTY_LOG(ERR, "Error with create socket thread: %s\n",