On Wed, Sep 09, 2020 at 05:09:23PM +0800, Weihang Li wrote:
> From: Yangyang Li <liyangyang20@xxxxxxxxxx>
>
> In order to improve performance by balancing the load between different
> banks of cache, the QPC cache is desigend to choose one of 8 banks
> according to lower 3 bits of QPN, and the CQC cache uses the lower 2 bits
> to choose one from 4 banks. The hns driver needs to count the number of
> QP/CQ on each bank and then assigns the QP/CQ being created to the bank
> with the minimum load first.
>
> Signed-off-by: Yangyang Li <liyangyang20@xxxxxxxxxx>
> Signed-off-by: Weihang Li <liweihang@xxxxxxxxxx>
> drivers/infiniband/hw/hns/hns_roce_alloc.c | 46 +++++++++++++++++++++++++++++
> drivers/infiniband/hw/hns/hns_roce_cq.c | 38 +++++++++++++++++++++++-
> drivers/infiniband/hw/hns/hns_roce_device.h | 8 +++++
> drivers/infiniband/hw/hns/hns_roce_qp.c | 39 ++++++++++++++++++++++--
> 4 files changed, 128 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/infiniband/hw/hns/hns_roce_alloc.c b/drivers/infiniband/hw/hns/hns_roce_alloc.c
> index a522cb2..cbe955c 100644
> +++ b/drivers/infiniband/hw/hns/hns_roce_alloc.c
> @@ -36,6 +36,52 @@
> #include "hns_roce_device.h"
> #include <rdma/ib_umem.h>
>
> +static int get_bit(struct hns_roce_bitmap *bitmap, u8 bankid,
> + u8 mod, unsigned long *obj)
> +{
> + unsigned long offset_bak = bitmap->last;
> + bool one_circle_flag = false;
> +
> + do {
> + *obj = find_next_zero_bit(bitmap->table, bitmap->max,
> + bitmap->last);
> + if (*obj >= bitmap->max) {
> + *obj = find_first_zero_bit(bitmap->table, bitmap->max);
> + one_circle_flag = true;
> + }
> +
> + bitmap->last = (*obj + 1);
> + if (bitmap->last == bitmap->max) {
> + bitmap->last = 0;
> + one_circle_flag = true;
> + }
> +
> + /* Not found after a round of search */
> + if (bitmap->last >= offset_bak && one_circle_flag)
> + return -EINVAL;
> +
> + } while (*obj % mod != bankid);
> +
> + return 0;
> +}
This looks like an ida, is there a reason it has to be open coded?
Jason
