RE: [PATCH v6] net/ice: add retry mechanism for DCF after failure

["Zhou, YidingX" <yidingx.zhou@intel.com>]

> -----Original Message-----
> From: Zhang, Qi Z <qi.z.zhang@intel.com>
> Sent: Thursday, July 7, 2022 2:56 PM
> To: Zhang, Peng1X <peng1x.zhang@intel.com>; Yang, Qiming
> <qiming.yang@intel.com>; dev@dpdk.org
> Subject: RE: [PATCH v6] net/ice: add retry mechanism for DCF after failure
> 
> 
> 
> > -----Original Message-----
> > From: Zhang, Peng1X <peng1x.zhang@intel.com>
> > Sent: Wednesday, July 6, 2022 10:17 PM
> > To: Yang, Qiming <qiming.yang@intel.com>; Zhang, Qi Z
> > <qi.z.zhang@intel.com>; dev@dpdk.org
> > Subject: [PATCH v6] net/ice: add retry mechanism for DCF after failure
> >
> > From: Peng Zhang <peng1x.zhang@intel.com>
> >
> > The origin design is if error happen during the step 3 of given
> > situation, it will return error directly without retry. While in
> > current patch, it will retry at every interval time during certain
> > time if receive designed error code 'VIRTCHNL_STATUS_ERR_RETRY'
> > from kernel. If retry succeed, rule can be continuously created.
> >
> > The given situation as following steps show:
> > step 1. Kernel PF and DPDK DCF are ready at the beginning.
> > step 2. A VF reset happen, kernel send an event to DCF and set STATE to
> pause.
> > step 3. Before DCF receive the event, it is possible a rule creation
> > is ongoing and virtual channel command from DCF to kernel PF is executing.
> > step 4. Then result of command is failure, it will lead to error code
> > return to DCF. Error code will be set as EINVAL, not EAGAIN.
> >
> > Fixes: daa714d55c72 ("net/ice: handle AdminQ command by DCF")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Peng Zhang <peng1x.zhang@intel.com>
> > ---
> >  v6 changes:
> >  - Add retry mechanism for DCF if receive designed error code from kernel.
> >  v5 changes:
> >  - Add retry mechanism for DCF if the result of sending virtual channel
> >    command is failure.
> >  v4 changes:
> >  - Add retry mechanism if the result of sending adminQ queue command is
> >    failure.
> >  v3 Changes:
> >  - Add the situation description, expected error code and incorrect
> >    error code in commit log.
> >  v2 Changes:
> >  - Modify DCF state checking mechanism.
> >
> >  drivers/common/iavf/virtchnl.h |  1 +
> >  drivers/net/ice/ice_dcf.c      | 32 ++++++++++++++++++++------------
> >  2 files changed, 21 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/common/iavf/virtchnl.h
> > b/drivers/common/iavf/virtchnl.h index f123daec8e..e15e3a4439 100644
> > --- a/drivers/common/iavf/virtchnl.h
> > +++ b/drivers/common/iavf/virtchnl.h
> > @@ -49,6 +49,7 @@ enum virtchnl_status_code {
> >  	VIRTCHNL_STATUS_ERR_CQP_COMPL_ERROR		= -39,
> >  	VIRTCHNL_STATUS_ERR_INVALID_VF_ID		= -40,
> >  	VIRTCHNL_STATUS_ERR_ADMIN_QUEUE_ERROR		= -53,
> > +	VIRTCHNL_STATUS_ERR_RETRY			= -63,
> 
> Where this error code be used?

This error code is not used in DPDK.  It's unnecessary to add it in vritchnl.h.
DPDK use IAVF_ERR_NOT_READY which has the same value -63.