[dpdk-stable] [PATCH] examples/eventdev: move eth stop to the end

[Feifei Wang]

Move eth stop code from "signal_handler" function to the end of "main"
function. There are two reasons for this:

First, this improves code maintenance and makes code look simple and clear.
Based on this change, after receiving the interrupt signal, "fdata->done"
is set as 1. Then the main thread will wait all worker lcores to jump out
of the loop. Finally, the main thread will stop and then close eth dev port.

Second, for older version, the main thread first stops eth dev port and then
waits the end of worker lcore. This may cause errors because it may stop the
eth dev port which worker lcores are using. This moving change can fix this
by waiting all worker threads to exit and then stop the eth dev port.

In the meanwhile, remove wmb in signal_handler.

This is because when the main lcore receive the stop signal, it stores 1
into fdata->done. And then the worker lcores load "fdata->done" and jump out
of the loop to stop running. Nothing should be stored after updating
fdata->done, so the wmb is unnecessary.

Fixes: 085edac2ca38 ("examples/eventdev_pipeline: support Tx adapter")
Cc: pbhagavatula at marvell.com
Cc: stable at dpdk.org

Suggested-by: Ruifeng Wang <ruifeng.wang at arm.com>
Signed-off-by: Feifei Wang <feifei.wang2 at arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang at arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli at arm.com>
---
 examples/eventdev_pipeline/main.c | 15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/examples/eventdev_pipeline/main.c b/examples/eventdev_pipeline/main.c
index 823f8b51c..ac2ace5c4 100644
--- a/examples/eventdev_pipeline/main.c
+++ b/examples/eventdev_pipeline/main.c
@@ -291,17 +291,6 @@ signal_handler(int signum)
 			rte_event_dev_dump(0, stdout);
 		once = 1;
 		fdata->done = 1;
-		rte_smp_wmb();
-
-		RTE_ETH_FOREACH_DEV(portid) {
-			rte_event_eth_rx_adapter_stop(portid);
-			rte_event_eth_tx_adapter_stop(portid);
-			if (rte_eth_dev_stop(portid) < 0)
-				printf("Failed to stop port %u", portid);
-		}
-
-		rte_eal_mp_wait_lcore();
-
 	}
 	if (signum == SIGTSTP)
 		rte_event_dev_dump(0, stdout);
@@ -465,6 +454,10 @@ main(int argc, char **argv)
 	}
 
 	RTE_ETH_FOREACH_DEV(portid) {
+		rte_event_eth_rx_adapter_stop(portid);
+		rte_event_eth_tx_adapter_stop(portid);
+		if (rte_eth_dev_stop(portid) < 0)
+			printf("Failed to stop port %u", portid);
 		rte_eth_dev_close(portid);
 	}
 
-- 
2.17.1