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Date:   Tue, 2 Feb 2021 14:14:24 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Parav Pandit <parav@nvidia.com>
CC:     Leon Romanovsky <leon@kernel.org>,
        Doug Ledford <dledford@redhat.com>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>
Subject: Re: [PATCH rdma-next 05/10] RDMA/core: Introduce and use API to read
 port immutable data
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On Tue, Feb 02, 2021 at 06:05:48PM +0000, Parav Pandit wrote:
> 
> 
> > From: Jason Gunthorpe <jgg@nvidia.com>
> > Sent: Tuesday, February 2, 2021 10:20 PM
> > 
> > On Wed, Jan 27, 2021 at 05:00:05PM +0200, Leon Romanovsky wrote:
> > > + * ib_port_immutable_read() - Read rdma port's immutable data
> > > + * @dev - IB device
> > > + * @port - port number whose immutable data to read. It starts with
> > index 1 and
> > > + *         valid upto including rdma_end_port().
> > > + */
> > > +const struct ib_port_immutable*
> > > +ib_port_immutable_read(struct ib_device *dev, unsigned int port) {
> > > +	WARN_ON(!rdma_is_port_valid(dev, port));
> > > +	return &dev->port_data[port].immutable; }
> > > +EXPORT_SYMBOL(ib_port_immutable_read);
> > 
> > Why add this function and only call it in one place?
> > 
> A helper API from core helps
> (a) to cut down mlx5 ib per port data structures and code around it
> (b) it also avoids the need to maintain such driver internal data for large port count (which is not done today)
>
I mean why not just access the pointer directly, is isn't in a private
header or anything

Jason