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Date: Fri, 16 Feb 2024 17:44:02 +0100
From: Daniel Wagner <dwagner@suse.de>
To: Christoph Hellwig <hch@lst.de>
Cc: James Smart <james.smart@broadcom.com>, 
	Keith Busch <kbusch@kernel.org>, Sagi Grimberg <sagi@grimberg.me>, Hannes Reinecke <hare@suse.de>, 
	linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v0 1/6] nvme-fabrics: introduce connect_sync option
Message-ID: <jfjchxptpfcpolpy2etiigflqvfcp2nzk53iwb6rx2zsdfd6by@h6ezfayjfqai>
References: <20240216084526.14133-1-dwagner@suse.de>
 <20240216084526.14133-2-dwagner@suse.de>
 <20240216094909.GA19961@lst.de>
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On Fri, Feb 16, 2024 at 10:49:09AM +0100, Christoph Hellwig wrote:
> On Fri, Feb 16, 2024 at 09:45:21AM +0100, Daniel Wagner wrote:
> > The TCP and RDMA transport are doing a synchronous connect, meaning the
> > syscal returns with the final result, that is. it either failed or
> > succeeded.
> > 
> > This isn't the case for FC. This transport just setups and triggers
> > the connect and returns without waiting on the result.
> 
> That's really weird and unexpected.  James, can you explain the reason
> behind this?

James answered this point on my attempt to make this synchronous:

https://lore.kernel.org/linux-nvme/0605ac36-16d5-2026-d3c6-62d346db6dfb@gmail.com/

> > Introduce a flag
> > to allow user space to control the behavior, wait or don't wait.
> 
> I'd expect this to be the default, but I'll wait to hear more about
> the rationale.  If we keep the async default the option looks sensible.

Ideally, we could agree on behavior which is the same for all
transports.