Re: [dpdk-dev] [PATCH] compressdev: implement API

[Ahmed Mansour <ahmed.mansour@nxp.com>]

On 3/2/2018 4:53 AM, Trahe, Fiona wrote:
>
>> On 3/1/2018 9:41 AM, Trahe, Fiona wrote:
>>> Hi Shally
>>>
>>> //snip//
>>>> [Shally] This looks better to me. So it mean app would always call xform_init() for stateless and attach
>> an
>>>> updated priv_xform to ops (depending upon if there's shareable or not). So it does not need to have
>>>> NULL pointer on priv_xform. right?
>>>>
>>> [Fiona] yes. The PMD must return a valid priv_xform pointer.
>> [Ahmed] What I understood is that the xform_init will be called once
>> initially. if the @flag returned is NONE_SHAREABLE then the application
>> must not attach two inflight ops to the same @priv_xform? Otherwise the
>> application can attach many ops in flight to the @priv_xform?
> [Fiona Yes. App calls the xform_init() once on a device where it plans to send stateless ops.
> If PMD returns shareable, then it doesn't need to call again and can attach this to every stateless op going to that device.
> If PMD returns SINGLE_OP then it must call xform_init() before every other 
> stateless op it wants to have inflight simultaneously. This does not mean it must be called before every op, 
> but probably will set up a batch of priv_xforms  - it can reuse each priv_xform once the op finishes with it.
[Ahmed] @Shally Can this complexity of managing the NONE_SHAREABLE mode
be pushed into the PMD? A flexible stockpile can be kept and maintained
by the PMD and it can be increased or decreased based on
low-water/high-water thresholds