From mboxrd@z Thu Jan  1 00:00:00 1970
From: Frederic Weisbecker <fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH 01/10] cgroups: add res_counter_write_u64() API
Date: Thu, 2 Feb 2012 14:56:11 +0100
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To: "Kirill A. Shutemov" <kirill-oKw7cIdHH8eLwutG50LtGA@public.gmane.org>
Cc: Aditya Kali <adityakali-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Tejun Heo <htejun-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, "Daniel P. Berrange" <berrange-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Max Kellermann <mk-xMchvyqCc6DQT0dZR+AlfA@public.gmane.org>, Tim Hockin <thockin-Rl2oBbRerpQdnm+yROfE0A@public.gmane.org>, Glauber Costa <glommer-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, Daniel J Walsh <dwalsh-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Mandeep Singh Baines <msb-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
List-Id: containers.vger.kernel.org

On Thu, Feb 02, 2012 at 02:33:22PM +0200, Kirill A. Shutemov wrote:
> On Wed, Feb 01, 2012 at 04:37:41AM +0100, Frederic Weisbecker wrote:
> > +#if BITS_PER_LONG == 32
> > +void res_counter_write_u64(struct res_counter *counter, int member, u64 val)
> > +{
> > +	unsigned long long *target;
> > +	unsigned long flags;
> > +
> > +	spin_lock_irqsave(&counter->lock, flags);
> > +	target = res_counter_member(counter, member);
> > +	*target = val;
> 
> Nitpick: What's the point to have temporary variable here?

Dunno, just a matter of habit, I use to avoid expressions
like *func(foo) = bar. It looks less readable to me but
perhaps it's because I'm not used to it.

> 
> > +	spin_unlock_irqrestore(&counter->lock, flags);
> > +}
> > +#else
> > +void res_counter_write_u64(struct res_counter *counter, int member, u64 val)
> > +{
> > +	unsigned long long *target;
> > +
> > +	target = res_counter_member(counter, member);
> > +	*target = val;
> 
> Ditto.
> 
> > +}
> > +#endif
> 
> -- 
>  Kirill A. Shutemov