netmap / LINUX realtime / ixgbevf: huge RX latencies

[Joe Buehler]

Here is what I start seeing in dmesg when I attempt to use the 4.2.1
ixgbevf driver as modified for netmap.

Joe Buehler

[  136.607019] 343.712201 [ 189] ixgbe_netmap_configure_srrctl not supported
[  136.610020] 343.715203 [ 189] ixgbe_netmap_configure_srrctl not supported
[  136.796698] ixgbevf 0000:00:08.0: NIC Link is Up 10 Gbps
[  136.953013] 344.058196 [ 189] ixgbe_netmap_configure_srrctl not supported
[  136.955014] 344.060198 [ 189] ixgbe_netmap_configure_srrctl not supported
[  136.997559] ixgbevf 0000:00:08.0: NIC Link is Up 10 Gbps
[  136.997908] 344.103090 [1653] nm_rxsync_prologue        eth0 RX0:
fail 'head < kring->nr_hwcur || head > kring->nr_hwtail' h 1 c 1 t 0 rh
1 rc 1 rt 0 hc 0 ht 0
[  136.999652] 344.104836 [1698] netmap_ring_reinit        called for
eth0 RX0
[  137.000568] 344.105751 [1653] nm_rxsync_prologue        eth0 RX0:
fail 'head < kring->nr_hwcur || head > kring->nr_hwtail' h 1 c 1 t 0 rh
1 rc 1 rt 0 hc 0 ht 0
[  137.002268] 344.107452 [1698] netmap_ring_reinit        called for
eth0 RX0
[  137.003165] 344.108349 [1653] nm_rxsync_prologue        eth0 RX0:
fail 'head < kring->nr_hwcur || head > kring->nr_hwtail' h 1 c 1 t 0 rh
1 rc 1 rt 0 hc 0 ht 0
[  137.004856] 344.110041 [1698] netmap_ring_reinit        called for
eth0 RX0
[  137.005752] 344.110936 [1653] nm_rxsync_prologue        eth0 RX0:
fail 'head < kring->nr_hwcur || head > kring->nr_hwtail' h 1 c 1 t 0 rh
1 rc 1 rt 0 hc 0 ht 0
[  137.007451] 344.112635 [1698] netmap_ring_reinit        called for
eth0 RX0
[  137.008343] 344.113527 [1653] nm_rxsync_prologue        eth0 RX0:
fail 'head < kring->nr_hwcur || head > kring->nr_hwtail' h 1 c 1 t 0 rh
1 rc 1 rt 0 hc 0 ht 0
[  137.010066] 344.115250 [1698] netmap_ring_reinit        called for
eth0 RX0
[  137.010953] 344.116137 [1698] netmap_ring_reinit        called for
eth0 RX0