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Date: Fri, 8 Sep 2023 08:36:08 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Maxime Chevallier <maxime.chevallier@bootlin.com>
Cc: "Russell King (Oracle)" <linux@armlinux.org.uk>, davem@davemloft.net,
 netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Lunn
 <andrew@lunn.ch>, Eric Dumazet <edumazet@google.com>, Paolo Abeni
 <pabeni@redhat.com>, Florian Fainelli <f.fainelli@gmail.com>, Heiner
 Kallweit <hkallweit1@gmail.com>, Vladimir Oltean <vladimir.oltean@nxp.com>,
 Oleksij Rempel <linux@rempel-privat.de>, =?UTF-8?B?Tmljb2zDsg==?= Veronese
 <nicveronese@gmail.com>, thomas.petazzoni@bootlin.com, Christophe Leroy
 <christophe.leroy@csgroup.eu>
Subject: Re: [RFC PATCH net-next 1/7] net: phy: introduce phy numbering and
 phy namespaces
Message-ID: <20230908083608.4f01bf2c@kernel.org>
In-Reply-To: <20230907141904.1be84216@pc-7.home>
References: <20230907092407.647139-1-maxime.chevallier@bootlin.com>
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On Thu, 7 Sep 2023 14:19:04 +0200 Maxime Chevallier wrote:
> > I think you can simplify this code quite a bit by using idr.
> > idr_alloc_cyclic() looks like it will do the allocation you want,
> > plus the IDR subsystem will store the pointer to the object (in
> > this case the phy device) and allow you to look that up. That
> > probably gets rid of quite a bit of code.
> > 
> > You will need to handle the locking around IDR however.  
> 
> Oh thanks for pointing this out. I had considered idr but I didn't spot
> the _cyclic() helper, and I had ruled that out thinking it would re-use
> ids directly after freeing them. I'll be more than happy to use that.

Perhaps use xarray directly, I don't think we need the @base offset or
quick access to @next which AFAICT is the only reason one would prefer
IDR?