When the flow_offload infrastructure was added, a couple of things that were previously possible for drivers to support in TC offload were not plumbed through, perhaps because the drivers in the tree did not fully or correctly implement them. The main issue was with statistics; in TC (and in the previous offload API) statistics are per-action, though generally only on 'delivery' actions like mirred, ok and shot. Actions also have an index, which may be supplied by the user, which allows the sharing of entities such as counters between multiple rules. The existing driver implementations did not support this, however, instead allocating a single counter per rule. The flow_offload API did not support this either, as (a) the action index never reached the driver, and (b) the TC_CLSFLOWER_STATS callback was only able to return a single set of stats which were added to all counters for actions on the rule. Patch #1 of this series fixes (a) by storing tcfa_index in a new action_index member of struct flow_action_entry, while patch #2 fixes (b) by adding a new callback, TC_CLSFLOWER_STATS_BYINDEX, which retrieves statistics for a specified action_index rather than by rule (although the rule cookie is still passed as well). Patch #3 adds flow_rule_match_cvlan(), analogous to flow_rule_match_vlan() but accessing FLOW_DISSECTOR_KEY_CVLAN instead of FLOW_DISSECTOR_KEY_VLAN, to allow offloading inner VLAN matches. This patch series does not include any users of these new interfaces; the driver in which I hope to use them does not yet exist upstream as it is for hardware which is still under development. However I've CCed developers of various other drivers that implement TC offload, in case any of them want to implement support. Otherwise I imagine that David won't be willing to take this without a user, in which case I'll save it to submit alongside the aforementioned unfinished driver (hence the RFC tags for now).
Edward Cree (3): flow_offload: copy tcfa_index into flow_action_entry flow_offload: restore ability to collect separate stats per action flow_offload: support CVLAN match include/net/flow_offload.h | 3 +++ include/net/pkt_cls.h | 2 ++ net/core/flow_offload.c | 7 +++++++ net/sched/cls_api.c | 1 + net/sched/cls_flower.c | 30 ++++++++++++++++++++++++++++++ 5 files changed, 43 insertions(+)
