Re: [PATCH v1 net-next 05/15] nvme-tcp: Add DDP offload control path

From: Shai Malin <malin1024@gmail.com>
To: Boris Pismenny <borispismenny@gmail.com>,
	Boris Pismenny <borisp@mellanox.com>,
	"kuba@kernel.org" <kuba@kernel.org>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"saeedm@nvidia.com" <saeedm@nvidia.com>,
	"hch@lst.de" <hch@lst.de>, "sagi@grimberg.me" <sagi@grimberg.me>,
	"axboe@fb.com" <axboe@fb.com>,
	"kbusch@kernel.org" <kbusch@kernel.org>,
	"viro@zeniv.linux.org.uk" <viro@zeniv.linux.org.uk>,
	"edumazet@google.com" <edumazet@google.com>
Cc: Yoray Zack <yorayz@mellanox.com>,
	"yorayz@nvidia.com" <yorayz@nvidia.com>,
	"boris.pismenny@gmail.com" <boris.pismenny@gmail.com>,
	Ben Ben-Ishay <benishay@mellanox.com>,
	"benishay@nvidia.com" <benishay@nvidia.com>,
	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Or Gerlitz <ogerlitz@mellanox.com>,
	"ogerlitz@nvidia.com" <ogerlitz@nvidia.com>,
	Shai Malin <smalin@marvell.com>, Ariel Elior <aelior@marvell.com>,
	Michal Kalderon <mkalderon@marvell.com>,
	Shai Malin <malin1024@gmail.com>
Subject: Re: [PATCH v1 net-next 05/15] nvme-tcp: Add DDP offload control path
Date: Tue, 15 Dec 2020 15:33:50 +0200	[thread overview]
Message-ID: <CAKKgK4xvS9SeM3NmNKDNe5oFxxfi0m_=iHCXeXX0DGcgzG_BBA@mail.gmail.com> (raw)
In-Reply-To: <0a272589-940c-6488-9cb9-1833400f38b3@gmail.com>

On 12/14/2020 08:38, Boris Pismenny wrote:
> On 10/12/2020 19:15, Shai Malin wrote:
> > diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index c0c33320fe65..ef96e4a02bbd 100644
> > --- a/drivers/nvme/host/tcp.c
> > +++ b/drivers/nvme/host/tcp.c
> > @@ -14,6 +14,7 @@
> >  #include <linux/blk-mq.h>
> >  #include <crypto/hash.h>
> >  #include <net/busy_poll.h>
> > +#include <net/tcp_ddp.h>
> >
> >  #include "nvme.h"
> >  #include "fabrics.h"
> > @@ -62,6 +63,7 @@ enum nvme_tcp_queue_flags {
> >       NVME_TCP_Q_ALLOCATED    = 0,
> >       NVME_TCP_Q_LIVE         = 1,
> >       NVME_TCP_Q_POLLING      = 2,
> > +     NVME_TCP_Q_OFFLOADS     = 3,
> >  };
> >
> > The same comment from the previous version - we are concerned that perhaps
> > the generic term "offload" for both the transport type (for the Marvell work)
> > and for the DDP and CRC offload queue (for the Mellanox work) may be
> > misleading and confusing to developers and to users.
> >
> > As suggested by Sagi, we can call this NVME_TCP_Q_DDP.
> >
>
> While I don't mind changing the naming here. I wonder  why not call the
> toe you use TOE and not TCP_OFFLOAD, and then offload is free for this?

Thanks - please do change the name to NVME_TCP_Q_DDP.
The Marvell nvme-tcp-offload patch series introducing the offloading of both the
TCP as well as the NVMe/TCP layer, therefore it's not TOE.

>
> Moreover, the most common use of offload in the kernel is for partial offloads
> like this one, and not for full offloads (such as toe).

Because each vendor might implement a different partial offload I
suggest naming it
with the specific technique which is used, as was suggested - NVME_TCP_Q_DDP.