RE: [PATCH V4 for-next 05/10] IB/core: Introduce Receive Work Queue indirection table

Steve Wise
2016-05-23T17:07:47Z

> Introduce Receive Work Queue (WQ) indirection table.
> This object can be used to spread incoming traffic to different
> receive Work Queues.
>
> A Receive WQ indirection table points to variable size of WQs.
> This table is given to a QP in downstream patches.
>
> Signed-off-by: Yishai Hadas <yishaih-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
> Signed-off-by: Matan Barak <matanb-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
> ---
> drivers/infiniband/core/verbs.c | 62
> +++++++++++++++++++++++++++++++++++++++++
> include/rdma/ib_verbs.h | 23 +++++++++++++++
> 2 files changed, 85 insertions(+)
>
> diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
> index c096cad..6b548d7 100644
> --- a/drivers/infiniband/core/verbs.c
> +++ b/drivers/infiniband/core/verbs.c
> @@ -1636,6 +1636,68 @@ int ib_modify_wq(struct ib_wq *wq, struct ib_wq_attr
> *wq_attr,
> }
> EXPORT_SYMBOL(ib_modify_wq);
>
> +/*
> + * ib_create_rwq_ind_table - Creates a RQ Indirection Table.
> + * @device: The device on which to create the rwq indirection table.
> + * @ib_rwq_ind_table_init_attr: A list of initial attributes required to
> + * create the Indirection Table.
> + *
> + * Note: The life time of ib_rwq_ind_table_init_attr->ind_tbl is not less
> + * than the created ib_rwq_ind_table object and the caller is responsible
> + * for its memory allocation/free.
> + */
> +struct ib_rwq_ind_table *ib_create_rwq_ind_table(struct ib_device *device,
> + struct
ib_rwq_ind_table_init_attr
> *init_attr)
> +{
> + struct ib_rwq_ind_table *rwq_ind_table;
> + int i;
> + u32 table_size;
> +
> + if (!device->create_rwq_ind_table)
> + return ERR_PTR(-ENOSYS);
> +
> + table_size = (1 << init_attr->log_ind_tbl_size);
> + rwq_ind_table = device->create_rwq_ind_table(device,
> + init_attr, NULL);
> + if (IS_ERR(rwq_ind_table))
> + return rwq_ind_table;
> +
> + rwq_ind_table->ind_tbl = init_attr->ind_tbl;
> + rwq_ind_table->log_ind_tbl_size = init_attr->log_ind_tbl_size;
> + rwq_ind_table->device = device;
> + rwq_ind_table->uobject = NULL;
> + atomic_set(&rwq_ind_table->usecnt, 0);
> +
> + for (i = 0; i < table_size; i++)
> + atomic_inc(&rwq_ind_table->ind_tbl[i]->usecnt);

Hey Yishai,

Why do you need usecnt on the individual tables allocated by the device? I see
them inc'd here and dec'd in destroy. But I don't see them used anywhere else?

Steve.