Re: [PATCH v3 for-next 12/12] RDMA/hns: Dump detailed driver-specific UCTX

[Leon Romanovsky <leon@kernel.org>]

On Tue, Jul 27, 2021 at 11:27:32AM +0800, Wenpeng Liang wrote:
> From: Xi Wang <wangxi11@huawei.com>
> 
> Dump DCA mem pool status in UCTX restrack.
> 
> Sample output:
> $ rdma res show ctx dev hns_0 -dd
>  dev hns_0 ctxn 7 pid 1410 comm python3 drv_dca-loading 37.50 drv_dca-total 65536 drv_dca-free 40960
>  dev hns_0 ctxn 8 pid 1410 comm python3 drv_dca-loading 0.00 drv_dca-total 0 drv_dca-free 0
> 
> Signed-off-by: Xi Wang <wangxi11@huawei.com>
> Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
> ---
>  drivers/infiniband/hw/hns/hns_roce_device.h   |  2 +
>  drivers/infiniband/hw/hns/hns_roce_main.c     |  1 +
>  drivers/infiniband/hw/hns/hns_roce_restrack.c | 85 +++++++++++++++++++++++++++
>  3 files changed, 88 insertions(+)

<...>

> +static int hns_roce_fill_dca_uctx(struct hns_roce_dca_ctx *ctx,
> +				  struct sk_buff *msg)
> +{
> +	char tmp_str[LOADING_PERCENT_CHARS];
> +	unsigned long flags;
> +	u64 total, free;
> +	u64 percent;
> +	u32 rem = 0;
> +
> +	spin_lock_irqsave(&ctx->pool_lock, flags);
> +	total = ctx->total_size;
> +	free = ctx->free_size;
> +	spin_unlock_irqrestore(&ctx->pool_lock, flags);
> +
> +	percent = calc_dca_loading_percent(total, free, &rem);
> +	scnprintf(tmp_str, sizeof(tmp_str), "%llu.%0*u\n", percent,
> +		  LOADING_PERCENT_SHIFT, rem);
> +
> +	if (rdma_nl_put_driver_string(msg, "dca-loading", tmp_str))
> +		goto err;

Please no, users can calculate percentage by themselves. We don't need
to complicate kernel for it.

Thanks

> +
> +	if (rdma_nl_put_driver_u64(msg, "dca-total", total))
> +		goto err;
> +
> +	if (rdma_nl_put_driver_u64(msg, "dca-free", free))
> +		goto err;
> +
> +	return 0;
> +
> +err:
> +	return -EMSGSIZE;
> +}
> +
> +int hns_roce_fill_res_ctx_entry(struct sk_buff *msg, struct ib_ucontext *ctx)
> +{
> +	struct hns_roce_dev *hr_dev = to_hr_dev(ctx->device);
> +	struct hns_roce_ucontext *uctx = to_hr_ucontext(ctx);
> +	struct nlattr *table_attr;
> +
> +	table_attr = nla_nest_start(msg, RDMA_NLDEV_ATTR_DRIVER);
> +	if (!table_attr)
> +		goto err;
> +
> +	if (hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_DCA_MODE) {
> +		if (hns_roce_fill_dca_uctx(&uctx->dca_ctx, msg))
> +			goto err_cancel_table;
> +	}
> +
> +	nla_nest_end(msg, table_attr);
> +
> +	return 0;
> +
> +err_cancel_table:
> +	nla_nest_cancel(msg, table_attr);
> +err:
> +	return -EMSGSIZE;
> +
> +	return 0;
> +}
> -- 
> 2.8.1
>