From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH v4 3/9] bus: add helper to find bus for a
	particular device
Date: Wed, 21 Jun 2017 14:11:05 +0200
Message-ID: <2413014.VjuBF7ha8b@xps>
References: <cover.1496876710.git.gaetan.rivet@6wind.com>
 <cover.1497999601.git.gaetan.rivet@6wind.com>
 <d24263e7a941d3b529fdc4f797f73efc5d9df723.1497999601.git.gaetan.rivet@6wind.com>
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Cc: dev@dpdk.org, Jan Blunck <jblunck@infradead.org>
To: Gaetan Rivet <gaetan.rivet@6wind.com>
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21/06/2017 01:29, Gaetan Rivet:
> +static int
> +cmp_rte_device(const struct rte_device *dev, const void *_dev2)

Better to rename dev into dev1.

> +{
> +	const struct rte_device *dev2 = _dev2;
> +
> +	return !(dev == dev2);

simpler: return dev1 != dev2

[...]
> +static int
> +bus_find_device(const struct rte_bus *bus, const void *_dev)
> +{
> +	struct rte_device *dev;
> +
> +	if (!bus->find_device)

It is preferred to check pointers against NULL.

> +		return -1;
> +	dev = bus->find_device(cmp_rte_device, _dev);
> +	return !dev;

Here also: return dev == NULL:

> +}
> +
> +struct rte_bus *rte_bus_find_by_device(const struct rte_device *dev)
> +{
> +	return rte_bus_find(bus_find_device, (const void *)dev, NULL);
> +}

Nice