MIME-Version: 1.0
In-Reply-To: <201211210953.20552.arnd@arndb.de>
References: <1353453142-4973-1-git-send-email-swarren@wwwdotorg.org> <201211210953.20552.arnd@arndb.de>
From: Grant Likely <grant.likely@secretlab.ca>
Date: Wed, 21 Nov 2012 10:06:16 +0000
Message-ID: <CACxGe6u5UBqVPrBqwn9rhjuBx4uCuuHKU=FcvSp0GJ2G8ogSNQ@mail.gmail.com>
Subject: Re: [PATCH V4 1/3] of: introduce for_each_matching_node_and_match()
To: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Warren <swarren@wwwdotorg.org>,
        Thomas Petazzoni <thomas.petazzoni@free-electrons.com>,
        Josh Cartwright <josh.cartwright@gmail.com>,
        Stephen Warren <swarren@nvidia.com>, John Stultz <johnstul@us.ibm.com>,
        linux-kernel@vger.kernel.org, Rob Herring <rob.herring@calxeda.com>,
        linux-tegra@vger.kernel.org, Olof Johansson <olof@lixom.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-arm-kernel@lists.infradead.org
Content-Type: text/plain; charset=ISO-8859-1
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1225
Lines: 26

On Wed, Nov 21, 2012 at 9:53 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> On Tuesday 20 November 2012, Stephen Warren wrote:
>> However, this results in iterating over table twice; the second time
>> inside of_match_node(). The implementation of for_each_matching_node()
>> already found the match, so this is redundant. Invent new function
>> of_find_matching_node_and_match() and macro
>> for_each_matching_node_and_match() to remove the double iteration,
>> thus transforming the above code to:
>>
>>     for_each_matching_node_and_match(np, table, &match)
>>
>> Signed-off-by: Stephen Warren <swarren@nvidia.com>
>
> This look useful, but I wonder if the interface would make more sense if you
> make the last argument to the macro a normal pointer, rather than a
> pointer-to-pointer. You can take the reference as part of the macro.

To me that makes for harder to understand code. It *looks* like an
argument to a normal function call, but it gets changed by the caller.

g.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/