Re: [PATCH v1 iproute2-next 2/3] rdma: print driver resource attributes

[Jason Gunthorpe <jgg@ziepe.ca>]

On Mon, May 07, 2018 at 08:53:16AM -0700, Steve Wise wrote:
> This enhancement allows printing rdma device-specific state, if provided
> by the kernel.  This is done in a generic manner, so rdma tool doesn't
> need to know about the details of every type of rdma device.
> 
> Driver attributes for a rdma resource are in the form of <key,
> [print_type], value> tuples, where the key is a string and the value can
> be any supported driver attribute.  The print_type attribute, if present,
> provides a print format to use vs the standard print format for the type.
> For example, the default print type for a PROVIDER_S32 value is "%d ",
> but "0x%x " if the print_type of PRINT_TYPE_HEX is included inthe tuple.
> 
> Driver resources are only printed when the -dd flag is present.
> If -p is present, then the output is formatted to not exceed 80 columns,
> otherwise it is printed as a single row to be grep/awk friendly.
> 
> Example output:
> 
> # rdma resource show qp lqpn 1028 -dd -p
> link cxgb4_0/- lqpn 1028 rqpn 0 type RC state RTS rq-psn 0 sq-psn 0 path-mig-state MIGRATED pid 0 comm [nvme_rdma]
>     sqid 1028 flushed 0 memsize 123968 cidx 85 pidx 85 wq_pidx 106 flush_cidx 85 in_use 0
>     size 386 flags 0x0 rqid 1029 memsize 16768 cidx 43 pidx 41 wq_pidx 171 msn 44 rqt_hwaddr 0x2a8a5d00
>     rqt_size 256 in_use 128 size 130 idx 43 wr_id 0xffff881057c03408 idx 40 wr_id 0xffff881057c033f0

Hey some of these look like kernel pointers.. That is a no-no.. What
is up there?

The wr_id often contains a pointer, right? So we cannot just pass it
to user space..

Jason