The RSS expansion algorithm is using a graph to find the possible expansion paths. A graph node with the 'explicit' flag will be skipped, if it is not found in the flow pattern.
The current implementation misses the case where the node with the explicit flag is in the middle of the expanded path. For example: testpmd> flow create 0 ingress pattern eth / ipv6 / udp / vxlan / end actions rss level 2 types tcp end / end The VLAN node has the explicit flag, so it is currently included in the expanded flow: ETH IPV6 UDP VXLAN END ETH IPV6 UDP VXLAN ETH VLAN IPV4 TCP END ETH IPV6 UDP VXLAN ETH VLAN IPV6 TCP END The fix is to skip the nodes with the explicit flag while iterating over the possible expansion paths. Using the above example, the flows will be: ETH IPV6 UDP VXLAN END ETH IPV6 UDP VXLAN ETH IPV4 TCP END ETH IPV6 UDP VXLAN ETH IPV6 TCP END Fixes: 3f02c7ff6815 ("net/mlx5: fix RSS expansion for inner tunnel VLAN") Cc: sta...@dpdk.org Signed-off-by: Lior Margalit <lmarga...@nvidia.com> Acked-by: Matan Azrad <ma...@nvidia.com> --- drivers/net/mlx5/mlx5_flow.c | 44 ++++++++++++++++++++++++------------ 1 file changed, 29 insertions(+), 15 deletions(-) diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c index 4762fa0f5f..6cf1bb810d 100644 --- a/drivers/net/mlx5/mlx5_flow.c +++ b/drivers/net/mlx5/mlx5_flow.c @@ -259,6 +259,26 @@ mlx5_flow_expand_rss_item_complete(const struct rte_flow_item *item) return ret; } +static const int * +mlx5_flow_expand_rss_skip_explicit(const struct mlx5_flow_expand_node graph[], + const int *next_node) +{ + const struct mlx5_flow_expand_node *node = NULL; + const int *next = next_node; + + while (next && *next) { + /* + * Skip the nodes with the MLX5_EXPANSION_NODE_EXPLICIT + * flag set, because they were not found in the flow pattern. + */ + node = &graph[*next]; + if (!(node->node_flags & MLX5_EXPANSION_NODE_EXPLICIT)) + break; + next = node->next; + } + return next; +} + #define MLX5_RSS_EXP_ELT_N 16 /** @@ -391,17 +411,8 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size, } } memset(flow_items, 0, sizeof(flow_items)); - next_node = node->next; - while (next_node) { - /* - * Skip the nodes with the MLX5_EXPANSION_NODE_EXPLICIT - * flag set, because they were not found in the flow pattern. - */ - node = &graph[*next_node]; - if (!(node->node_flags & MLX5_EXPANSION_NODE_EXPLICIT)) - break; - next_node = node->next; - } + next_node = mlx5_flow_expand_rss_skip_explicit(graph, + node->next); stack[stack_pos] = next_node; node = next_node ? &graph[*next_node] : NULL; while (node) { @@ -438,7 +449,8 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size, /* Go deeper. */ if (!(node->node_flags & MLX5_EXPANSION_NODE_OPTIONAL) && node->next) { - next_node = node->next; + next_node = mlx5_flow_expand_rss_skip_explicit(graph, + node->next); if (stack_pos++ == MLX5_RSS_EXP_ELT_N) { rte_errno = E2BIG; return -rte_errno; @@ -446,15 +458,17 @@ mlx5_flow_expand_rss(struct mlx5_flow_expand_rss *buf, size_t size, stack[stack_pos] = next_node; } else if (*(next_node + 1)) { /* Follow up with the next possibility. */ - ++next_node; + next_node = mlx5_flow_expand_rss_skip_explicit(graph, + ++next_node); } else { /* Move to the next path. */ if (stack_pos) next_node = stack[--stack_pos]; - next_node++; + next_node = mlx5_flow_expand_rss_skip_explicit(graph, + ++next_node); stack[stack_pos] = next_node; } - node = *next_node ? &graph[*next_node] : NULL; + node = next_node && *next_node ? &graph[*next_node] : NULL; }; return lsize; } -- 2.25.1