Re: [dpdk-dev] [EXT] [PATCH 1/5] examples/l2fwd-event: free resources in case of error

[Sunil Kumar Kori <skori@marvell.com>]

>-----Original Message-----
>From: Muhammad Bilal <m.bilal@emumba.com>
>Sent: Tuesday, May 19, 2020 2:25 PM
>To: declan.doherty@intel.com; tomasz.kantecki@intel.com; Pavan Nikhilesh
>Bhagavatula <pbhagavatula@marvell.com>; Sunil Kumar Kori
><skori@marvell.com>
>Cc: dev@dpdk.org; Muhammad Bilal <m.bilal@emumba.com>
>Subject: [EXT] [PATCH 1/5] examples/l2fwd-event: free resources in case of
>error
>
>External Email
>
>----------------------------------------------------------------------
>Freeing the resources and call rte_eal_cleanup in case of error exit.
>Signed-off-by: Muhammad Bilal <m.bilal@emumba.com>
>---
> examples/l2fwd-event/main.c | 43 ++++++++++++++++++++++++++++++-------
> 1 file changed, 35 insertions(+), 8 deletions(-)
>
>diff --git a/examples/l2fwd-event/main.c b/examples/l2fwd-event/main.c
>index 9593ef11e..442a664e9 100644
>--- a/examples/l2fwd-event/main.c
>+++ b/examples/l2fwd-event/main.c
>@@ -556,13 +556,26 @@ signal_handler(int signum)
> 	}
> }
>
>+static void
>+stop_and_close_eth_dev(uint16_t portid) {
>+	RTE_ETH_FOREACH_DEV(portid) {
>+		printf("Closing port %d...", portid);
>+		rte_eth_dev_stop(portid);
>+		rte_eth_dev_close(portid);
>+		printf(" Done\n");
>+	}
>+	rte_eal_cleanup();
>+}
>+
> int
> main(int argc, char **argv)
> {
> 	struct l2fwd_resources *rsrc;
> 	uint16_t nb_ports_available = 0;
> 	uint32_t nb_ports_in_mask = 0;
>-	uint16_t port_id, last_port;
>+	uint16_t port_id = 0;
>+	uint16_t last_port;
> 	uint32_t nb_mbufs;
> 	uint16_t nb_ports;
> 	int i, ret;
>@@ -581,20 +594,26 @@ main(int argc, char **argv)
>
> 	/* parse application arguments (after the EAL ones) */
> 	ret = l2fwd_event_parse_args(argc, argv, rsrc);
>-	if (ret < 0)
>+	if (ret < 0) {
>+		stop_and_close_eth_dev(port_id);
> 		rte_panic("Invalid L2FWD arguments\n");
>+	}
>
IMO, up to this point only eal_init is done so rte_eal_cleanup will be sufficient for this.
Also another way to handle this, use rte_exit instead rte_panic. rte_exit internally calls
rte_eal_cleanup. Refer l2fwd.

Also I think, it is better to release the relevant resources on error.

> 	printf("MAC updating %s\n", rsrc->mac_updating ? "enabled" :
> 			"disabled");
>
> 	nb_ports = rte_eth_dev_count_avail();
>-	if (nb_ports == 0)
>+	if (nb_ports == 0) {
>+		stop_and_close_eth_dev(port_id);
> 		rte_panic("No Ethernet ports - bye\n");
>+	}
>
Same as above.

> 	/* check port mask to possible port mask */
>-	if (rsrc->enabled_port_mask & ~((1 << nb_ports) - 1))
>+	if (rsrc->enabled_port_mask & ~((1 << nb_ports) - 1)) {
>+		stop_and_close_eth_dev(port_id);
> 		rte_panic("Invalid portmask; possible (0x%x)\n",
> 			(1 << nb_ports) - 1);
>+	}
>
Same as above.

> 	if (!rsrc->port_pairs) {
> 		last_port = 0;
>@@ -621,8 +640,10 @@ main(int argc, char **argv)
> 			rsrc->dst_ports[last_port] = last_port;
> 		}
> 	} else {
>-		if (check_port_pair_config(rsrc) < 0)
>+		if (check_port_pair_config(rsrc) < 0) {
>+			stop_and_close_eth_dev(port_id);
> 			rte_panic("Invalid port pair config\n");
>+		}
> 	}
>
> 	nb_mbufs = RTE_MAX(nb_ports * (RTE_TEST_RX_DESC_DEFAULT +
>@@ -634,12 +655,16 @@ main(int argc, char **argv)
> 	rsrc->pktmbuf_pool = rte_pktmbuf_pool_create("mbuf_pool",
> 			nb_mbufs, MEMPOOL_CACHE_SIZE, 0,
> 			RTE_MBUF_DEFAULT_BUF_SIZE, rte_socket_id());
>-	if (rsrc->pktmbuf_pool == NULL)
>+	if (rsrc->pktmbuf_pool == NULL) {
>+		stop_and_close_eth_dev(port_id);
> 		rte_panic("Cannot init mbuf pool\n");
>+	}
>
> 	nb_ports_available = l2fwd_event_init_ports(rsrc);
>-	if (!nb_ports_available)
>+	if (!nb_ports_available) {
>+		stop_and_close_eth_dev(port_id);
> 		rte_panic("All available ports are disabled. Please set
>portmask.\n");
>+	}
>
> 	/* Configure eventdev parameters if required */
> 	if (rsrc->event_mode)
>@@ -659,9 +684,11 @@ main(int argc, char **argv)
> 			continue;
>
> 		ret = rte_eth_dev_start(port_id);
>-		if (ret < 0)
>+		if (ret < 0) {
>+			stop_and_close_eth_dev(port_id);
> 			rte_panic("rte_eth_dev_start:err=%d, port=%u\n",
>ret,
> 				  port_id);
>+		}
> 	}
>
> 	if (rsrc->event_mode)
>--
>2.17.1