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References: <20210923172647.72738-1-ben.widawsky@intel.com>
 <20210923172647.72738-2-ben.widawsky@intel.com>
In-Reply-To: <20210923172647.72738-2-ben.widawsky@intel.com>
From: Dan Williams <dan.j.williams@intel.com>
Date: Mon, 27 Sep 2021 16:13:41 -0700
Message-ID: <CAPcyv4gXiW7ap3dULCwcWLy1qkGOrgdJTBonfw5V7h6ZOQ-+AQ@mail.gmail.com>
Subject: Re: [PATCH v2 1/9] cxl: Convert "RBI" to enum
To: Ben Widawsky <ben.widawsky@intel.com>
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Please spell out "register block indicator" in the subject so that the
shortlog remains somewhat readable.

On Thu, Sep 23, 2021 at 10:27 AM Ben Widawsky <ben.widawsky@intel.com> wrote:
>
> In preparation for passing around the Register Block Indicator (RBI) as
> a parameter, it is desirable to convert the type to an enum so that the
> interface can use a well defined type checked parameter.

C wouldn't type check this unless it failed an integer conversion,
right? It would need to be a struct to get useful type checking.

I don't mind this for the self documenting properties it has for the
functions that will take this as a parameter, but maybe clarify what
you mean by type checked parameter?

>
> As a result of this change, should future versions of the spec add
> sparsely defined identifiers, it could become a problem if checking for
> invalid identifiers since the code currently checks for the max
> identifier. This is not an issue with current spec, and the algorithm to
> obtain the register blocks will change before those possible additions
> are made.

In general let's not spend changelog space trying to guess what future
specs may or may not do. I.e. I think this text can be dropped,
especially because enums can support sparse number spaces.