From: Petr Machata petrm@nvidia.com
[ Upstream commit 0106668cd2f91bf913fb78972840dedfba80a3c3 ]
When trapping packets for on-CPU processing, Spectrum machines differentiate between control and non-control traps. Traffic trapped through non-control traps is treated as data and kept in shared buffer in pools 0-4. Traffic trapped through control traps is kept in the dedicated control buffer 9. The advantage of marking traps as control is that pressure in the data plane does not prevent the control traffic to be processed.
When the LLDP trap was introduced, it was marked as a control trap. But then in commit aed4b5721143 ("mlxsw: spectrum: PTP: Hook into packet receive path"), PTP traps were introduced. Because Ethernet-encapsulated PTP packets look to the Spectrum-1 ASIC as LLDP traffic and are trapped under the LLDP trap, this trap was reconfigured as non-control, in sync with the PTP traps.
There is however no requirement that PTP traffic be handled as data. Besides, the usual encapsulation for PTP traffic is UDP, not bare Ethernet, and that is in deployments that even need PTP, which is far less common than LLDP. This is reflected by the default policer, which was not bumped up to the 19Kpps / 24Kpps that is the expected load of a PTP-enabled Spectrum-1 switch.
Marking of LLDP trap as non-control was therefore probably misguided. In this patch, change it back to control.
Reported-by: Maksym Yaremchuk maksymy@nvidia.com Signed-off-by: Petr Machata petrm@nvidia.com Signed-off-by: Ido Schimmel idosch@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c index 47b061b99160..ed4d0d3448f3 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c @@ -864,7 +864,7 @@ static const struct mlxsw_sp_trap_item mlxsw_sp_trap_items_arr[] = { .trap = MLXSW_SP_TRAP_CONTROL(LLDP, LLDP, TRAP), .listeners_arr = { MLXSW_RXL(mlxsw_sp_rx_ptp_listener, LLDP, TRAP_TO_CPU, - false, SP_LLDP, DISCARD), + true, SP_LLDP, DISCARD), }, }, {