RE: [PATCH v2 net-next] net: fec: Convert fec driver to use lock guards

[Wei Fang]

> -----Original Message-----
> From: Andrew Lunn <andrew@xxxxxxx>
> Sent: 2024年5月11日 22:30
> To: Wei Fang <wei.fang@xxxxxxx>
> Cc: davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx;
> pabeni@xxxxxxxxxx; Shenwei Wang <shenwei.wang@xxxxxxx>; Clark Wang
> <xiaoning.wang@xxxxxxx>; richardcochran@xxxxxxxxx;
> netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; imx@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v2 net-next] net: fec: Convert fec driver to use lock guards
> 
> On Sat, May 11, 2024 at 11:02:29AM +0800, Wei Fang wrote:
> > The Scope-based resource management mechanism has been introduced
> into
> > kernel since the commit 54da6a092431 ("locking: Introduce __cleanup()
> > based infrastructure"). The mechanism leverages the 'cleanup'
> > attribute provided by GCC and Clang, which allows resources to be
> > automatically released when they go out of scope.
> > Therefore, convert the fec driver to use guard() and scoped_guard()
> > defined in linux/cleanup.h to automate lock lifetime control in the
> > fec driver.
> 
> Sorry, it has been decided for netdev we don't want these sort of conversions,
> at least not yet. The main worry is backporting fixes. It is likely such bcakports
> are going to be harder, and also more error prone, since the context is quite
> different.
> 
> If done correctly, scoped_guard() {} could be useful, and avoid issues. So we are
> O.K. with that in new code. That will also allow us to get some experience with
> it over the next few years. Maybe we will then re-evaluate this decision about
> converting existing code.
> 
Okay, it's fine, thanks.
>