[dpdk-dev] [PATCH v3 4/5] testpmd: handle all rxqs in rss setup

[Zhihong Wang]

This patch removes constraints in rxq handling when multiqueue is enabled
to handle all the rxqs.

Current testpmd forces a dedicated core for each rxq, some rxqs may be
ignored when core number is less than rxq number, and that causes confusion
and inconvenience.

One example: One Red Hat engineer was doing multiqueue test, there're 2
ports in guest each with 4 queues, and testpmd was used as the forwarding
engine in guest, as usual he used 1 core for forwarding, as a results he
only saw traffic from port 0 queue 0 to port 1 queue 0, then a lot of
emails and quite some time are spent to root cause it, and of course it's
caused by this unreasonable testpmd behavior.  

Moreover, even if we understand this behavior, if we want to test the
above case, we still need 8 cores for a single guest to poll all the
rxqs, obviously this is too expensive.

We met quite a lot cases like this, one recent example:
http://openvswitch.org/pipermail/dev/2016-June/072110.html


Signed-off-by: Zhihong Wang <zhihong.wang at intel.com>
---
 app/test-pmd/config.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c
index ede7c78..4719a08 100644
--- a/app/test-pmd/config.c
+++ b/app/test-pmd/config.c
@@ -1199,19 +1199,13 @@ rss_fwd_config_setup(void)
 	cur_fwd_config.nb_fwd_ports = nb_fwd_ports;
 	cur_fwd_config.nb_fwd_streams =
 		(streamid_t) (nb_q * cur_fwd_config.nb_fwd_ports);
-	if (cur_fwd_config.nb_fwd_streams > cur_fwd_config.nb_fwd_lcores)
-		cur_fwd_config.nb_fwd_streams =
-			(streamid_t)cur_fwd_config.nb_fwd_lcores;
-	else
-		cur_fwd_config.nb_fwd_lcores =
-			(lcoreid_t)cur_fwd_config.nb_fwd_streams;
 
 	/* reinitialize forwarding streams */
 	init_fwd_streams();
 
 	setup_fwd_config_of_each_lcore(&cur_fwd_config);
 	rxp = 0; rxq = 0;
-	for (lc_id = 0; lc_id < cur_fwd_config.nb_fwd_lcores; lc_id++) {
+	for (lc_id = 0; lc_id < cur_fwd_config.nb_fwd_streams; lc_id++) {
 		struct fwd_stream *fs;
 
 		fs = fwd_streams[lc_id];
-- 
2.5.0