Modifying an existing flow
An existing flow rule can be modified using the DPDK API, rte_flow_actions_update. The following example demonstrates how to modify an existing flow rule by changing its action from forwarding to a queue to transmitting to a specific port (port 1 in this case).
struct rte_flow_action_port_id port_id = { .id = 1 };
struct rte_flow_action action[] = {
[0] = { .type = RTE_FLOW_ACTION_TYPE_PORT_ID, .conf = &port_id },
[1] = { .type = RTE_FLOW_ACTION_TYPE_END }};
struct rte_flow_error error;
int ret = rte_flow_actions_update(PORT_ID, flow, action, &error);
if (ret) {
/* Error handling */
}
flow that needs to be modified in
rte_flow_actions_update is the existing flow rule that has been created
using rte_flow_create (see Forwarding all traffic to a queue).
Note:
Modifying existing flow rules do not apply to the flow rules as follows.
- Flow rules assigned to group 0.
- Flow rules containing patterns without specific values.
- Flow rule 1: Filters IPv4 traffic and jumps to group 1. See the following
testpmd
command.
flow create 0 group 0 pattern ipv4 end actions jump group 1
- Flow rule 2: Forwards IPv4 traffic to queue 0. See the following
testpmd
command.
flow create 0 group 1 pattern end actions queue index 0 / end
- Flow rule 3: Transmits frames with IP 8.8.8.8 on port 1. See the following
testpmd
command.
flow create 0 group 1 pattern ipv4 dst is 8.8.8.8 / end action port_id id 1 / end