mlxsw: spectrum_span: Add SPAN probability rate support

Currently, every packet that matches a mirroring trigger (e.g., received
packets, buffer dropped packets) is mirrored. Spectrum-2 and later ASICs
support mirroring with probability, where every 1 in N matched packets
is mirrored.

Extend the API that creates the binding between the trigger and the SPAN
agent with a probability rate parameter, which is an attribute of the
trigger. Set it to '1' to maintain existing behavior.

Subsequent patches will use it to perform more sophisticated sampling,
by mirroring packets to the CPU with probability.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_matchall.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_matchall.c
index f30599a..2b7652b 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_matchall.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_matchall.c
@@ -51,6 +51,7 @@ mlxsw_sp_mall_port_mirror_add(struct mlxsw_sp_port *mlxsw_sp_port,
        trigger = mall_entry->ingress ? MLXSW_SP_SPAN_TRIGGER_INGRESS :
                                        MLXSW_SP_SPAN_TRIGGER_EGRESS;
        parms.span_id = mall_entry->mirror.span_id;
+       parms.probability_rate = 1;
        err = mlxsw_sp_span_agent_bind(mlxsw_sp, trigger, mlxsw_sp_port,
                                       &parms);
        if (err)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c
index 9d16823..baf17c0 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c
@@ -1341,6 +1341,7 @@ static int mlxsw_sp_qevent_span_configure(struct mlxsw_sp *mlxsw_sp,
                goto err_analyzed_port_get;
 
        trigger_parms.span_id = span_id;
+       trigger_parms.probability_rate = 1;
        err = mlxsw_sp_span_agent_bind(mlxsw_sp, qevent_binding->span_trigger, mlxsw_sp_port,
                                       &trigger_parms);
        if (err)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
index 7711ace..3398cc0 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
@@ -1231,8 +1231,12 @@ __mlxsw_sp_span_trigger_port_bind(struct mlxsw_sp_span *span,
                return -EINVAL;
        }
 
+       if (trigger_entry->parms.probability_rate > MLXSW_REG_MPAR_RATE_MAX)
+               return -EINVAL;
+
        mlxsw_reg_mpar_pack(mpar_pl, trigger_entry->local_port, i_e, enable,
-                           trigger_entry->parms.span_id, 1);
+                           trigger_entry->parms.span_id,
+                           trigger_entry->parms.probability_rate);
        return mlxsw_reg_write(span->mlxsw_sp->core, MLXSW_REG(mpar), mpar_pl);
 }
 
@@ -1366,8 +1370,11 @@ mlxsw_sp2_span_trigger_global_bind(struct mlxsw_sp_span_trigger_entry *
                return -EINVAL;
        }
 
+       if (trigger_entry->parms.probability_rate > MLXSW_REG_MPAGR_RATE_MAX)
+               return -EINVAL;
+
        mlxsw_reg_mpagr_pack(mpagr_pl, trigger, trigger_entry->parms.span_id,
-                            1);
+                            trigger_entry->parms.probability_rate);
        return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(mpagr), mpagr_pl);
 }
 
@@ -1565,7 +1572,9 @@ int mlxsw_sp_span_agent_bind(struct mlxsw_sp *mlxsw_sp,
                                                         trigger,
                                                         mlxsw_sp_port);
        if (trigger_entry) {
-               if (trigger_entry->parms.span_id != parms->span_id)
+               if (trigger_entry->parms.span_id != parms->span_id ||
+                   trigger_entry->parms.probability_rate !=
+                   parms->probability_rate)
                        return -EINVAL;
                refcount_inc(&trigger_entry->ref_count);
                goto out;

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
index 6e84cc0..dea1c0d 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
@@ -48,6 +48,7 @@ enum mlxsw_sp_span_trigger {
 
 struct mlxsw_sp_span_trigger_parms {
        int span_id;
+       u32 probability_rate;
 };
 
 struct mlxsw_sp_span_agent_parms {