On Tue, Jul 27, 2021 at 11:27:21AM +0800, Wenpeng Liang wrote:
> From: Xi Wang <wangxi11@xxxxxxxxxx>
>
> The hip09 introduces the DCA(Dynamic context attachment) feature which
> supports many RC QPs to share the WQE buffer in a memory pool, this will
> reduce the memory consumption when there are too many QPs are inactive.
>
> If a QP enables DCA feature, the WQE's buffer will not be allocated when
> creating. But when the users start to post WRs, the hns driver will
> allocate a buffer from the memory pool and then fill WQEs which tagged with
> this QP's number.
>
> The hns ROCEE will stop accessing the WQE buffer when the user polled all
> of the CQEs for a DCA QP, then the driver will recycle this WQE's buffer
> to the memory pool.
>
> This patch adds a group of methods to support the user space register
> buffers to a memory pool which belongs to the user context. The hns kernel
> driver will update the pages state in this pool when the user calling the
> post/poll methods and the user driver can get the QP's WQE buffer address
> by the key and offset which queried from kernel.
>
> Signed-off-by: Xi Wang <wangxi11@xxxxxxxxxx>
> Signed-off-by: Wenpeng Liang <liangwenpeng@xxxxxxxxxx>
> ---
> drivers/infiniband/hw/hns/Makefile | 2 +-
> drivers/infiniband/hw/hns/hns_roce_dca.c | 343 ++++++++++++++++++++++++++++
> drivers/infiniband/hw/hns/hns_roce_dca.h | 22 ++
> drivers/infiniband/hw/hns/hns_roce_device.h | 9 +
> drivers/infiniband/hw/hns/hns_roce_main.c | 27 ++-
> include/uapi/rdma/hns-abi.h | 27 +++
> 6 files changed, 427 insertions(+), 3 deletions(-)
> create mode 100644 drivers/infiniband/hw/hns/hns_roce_dca.c
> create mode 100644 drivers/infiniband/hw/hns/hns_roce_dca.h
<...>
> +static struct hns_dca_page_state *alloc_dca_states(void *pages, int count)
> +{
> + struct hns_dca_page_state *states;
> +
> + states = kcalloc(count, sizeof(*states), GFP_NOWAIT);
GFP_NOWAIT ????
Why do you use this flag while in the function before you used classic GFP_KERNEL?
Thanks
