Packet pacing is a feature to control packet injection rate in arbitrary rates. One typical use case is for streaming vendors to control the bandwidth of different customers based on service coverage. Packet pacing is a rate limiting and shaping for a QP (SQ for RAW QP), set and change the rate is done by modifying QP. This series of patch made the following high level changes: 1. Report rate limit capabilities through user data. Reported capabilities include: The maximum and minimum rate limit in kbps supported by packet pacing; Bitmap showing which QP types are supported by packet pacing operation. 2. Extend modify QP interface for growing attributes. Add rate limit support to the extended interface. 3. Enable mlx5-based hardware to be able to update the rate limit for RAW QP packet. Rate limit could also be achieved by using path record data(static_rate), however, compare to packet pacing, the drawbacks are: - The rate field is only u8, and uses IB standard rate enumerations. Users have very limited options. Packet pacing supports arbitrary rates with a resolution of 1kbps. - Path record data doesn't apply to Raw Ethernet QPs, because these are not 1:1 connected as RC, nor use address handles as UD. The rate_limit configuration came from the application like required BW for the streaming and not from the fabric (SM). Both of these features are limiting the rate but coming from a different entities and required separate fields. The actual limit should be the minimum of both of them (if both features apply). This patch series depend on the following patches: Add port counter support for raw packet QP [1] http://www.spinics.net/lists/linux-rdma/msg39607.html Available in the "topic/packet_pacing" topic branch of this git repo: git://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma.git Or for browsing: https://git.kernel.org/cgit/linux/kernel/git/leon/linux-rdma.git/log/?h=topic/packet_pacing Thanks. Changes from V0: 1. New bit masks IB_USER_LEGACY_LAST_QP_ATTR_MASK and IB_USER_LAST_QP_ATTR_MASK are added to detect non-supported masks for legacy/ex commands. 2. The ib_uverbs_ex_modify_qp should call uhw rather than ucore at the end. Bodong Wang (4): IB/mlx5: Report mlx5 packet pacing capabilities when querying device IB/core: Support rate limit for packet pacing IB/uverbs: Extend modify_qp and support packet pacing IB/mlx5: Update the rate limit according to user setting for RAW QP drivers/infiniband/core/uverbs.h | 1 + drivers/infiniband/core/uverbs_cmd.c | 192 ++++++++++++++++++++++------------ drivers/infiniband/core/uverbs_main.c | 1 + drivers/infiniband/core/verbs.c | 2 + drivers/infiniband/hw/mlx5/main.c | 16 ++- drivers/infiniband/hw/mlx5/mlx5_ib.h | 1 + drivers/infiniband/hw/mlx5/qp.c | 74 +++++++++++-- include/rdma/ib_verbs.h | 2 + include/uapi/rdma/ib_user_verbs.h | 21 ++++ include/uapi/rdma/mlx5-abi.h | 13 +++ 10 files changed, 245 insertions(+), 78 deletions(-) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
