[dpdk-stable] [PATCH v4 1/3] doc: fix core enabled bug for eventdev pipeline example

[Feifei Wang <feifei.wang2@arm.com>]

In the case that the cores are isolated, if "-l" or "-c" parameter is not
added, the cores will not be enabled and can not launch worker function
correctly. In the meanwhile, no error information is reported.

For example:
totally CPUs:16
isolated CPUs:1-8
command: sudo gdb -args ./dpdk-eventdev_pipeline --vdev event_sw0 \
        -- -r1 -t1 -e4 -w F00 -s4 -n0 -c32 -W1000 -D

cores information:
rte_config->lcore_role = {ROLE_RTE, ROLE_OFF, ROLE_OFF, ROLE_OFF,
                          ROLE_OFF, ROLE_OFF, ROLE_OFF, ROLE_OFF,
                          ROLE_OFF, ROLE_RTE, ROLE_RTE, ROLE_RTE,
                          ROLE_RTE, ROLE_RTE, ROLE_RTE, ROLE_RTE}

output information:
...
[main()] lcore 9 executing worker, using eventdev port 0
[main()] lcore 10 executing worker, using eventdev port 1
[main()] lcore 11 executing worker, using eventdev port 2

This is because "RTE_LCORE_FOREACH_WORKER" chooses the enabled core. In
the case that the cores are isolated, "the lcore_role" flag of isolated
cores are set as "ROLE_OFF" by default(not enabled). So if we choose
these isolated cores as workers, "RTE_LCORE_FOREACH_WORKER" will ignore
these cores and not launch worker functions on them.

To fix this, add "-l" parameters to doc and add lcore enabled check.

Fixes: 1094ca96689c ("doc: add SW eventdev pipeline to sample app guide")
Cc: harry.van.haaren@intel.com
Cc: stable@dpdk.org

Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---
 doc/guides/sample_app_ug/eventdev_pipeline.rst | 5 +++--
 examples/eventdev_pipeline/main.c              | 7 ++++++-
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/doc/guides/sample_app_ug/eventdev_pipeline.rst b/doc/guides/sample_app_ug/eventdev_pipeline.rst
index 4508c3dcc..19ff53803 100644
--- a/doc/guides/sample_app_ug/eventdev_pipeline.rst
+++ b/doc/guides/sample_app_ug/eventdev_pipeline.rst
@@ -34,6 +34,7 @@ options.
 An example eventdev pipeline running with the software eventdev PMD using
 these settings is shown below:
 
+ * ``-l 0,2,8-15``: lcore to use
  * ``-r1``: core mask 0x1 for RX
  * ``-t1``: core mask 0x1 for TX
  * ``-e4``: core mask 0x4 for the software scheduler
@@ -46,8 +47,8 @@ these settings is shown below:
 
 .. code-block:: console
 
-    ./<build_dir>/examples/dpdk-eventdev_pipeline --vdev event_sw0 -- -r1 -t1 \
-    -e4 -w FF00 -s4 -n0 -c32 -W1000 -D
+    ./<build_dir>/examples/dpdk-eventdev_pipeline -l 0,2,8-15 --vdev event_sw0 \
+    -- -r1 -t1 -e4 -w FF00 -s4 -n0 -c32 -W1000 -D
 
 The application has some sanity checking built-in, so if there is a function
 (e.g.; the RX core) which doesn't have a cpu core mask assigned, the application
diff --git a/examples/eventdev_pipeline/main.c b/examples/eventdev_pipeline/main.c
index 823f8b51c..e9a591134 100644
--- a/examples/eventdev_pipeline/main.c
+++ b/examples/eventdev_pipeline/main.c
@@ -239,8 +239,13 @@ parse_app_args(int argc, char **argv)
 
 		if (fdata->worker_core[i])
 			cdata.num_workers++;
-		if (core_in_use(i))
+		if (core_in_use(i)) {
+			if (!rte_lcore_is_enabled(i)) {
+				printf("error: lcore %d is not enabled in lcore list\n", i);
+				rte_exit(EXIT_FAILURE, "check lcore params failed\n");
+			}
 			cdata.active_cores++;
+		}
 	}
 }
 
-- 
2.25.1