Re: [PATCH 2/7] revoke: add f_light flag for struct file

From: Eric Dumazet
Date: Fri Mar 09 2007 - 12:47:24 EST


On Friday 09 March 2007 17:11, Benjamin LaHaise wrote:
> On Fri, Mar 09, 2007 at 12:13:35PM +0100, Eric Dumazet wrote:
> > Then just drop the fget_light() 'optimisation' and always take a
> > reference (atomic on f_count) regardless of single-thread or not. Instead
> > of dirtying f_light, just do the straightforward thing and be with it.
> >
> > (that is : fget_light() = fget() = no more keeping fput_needed
> > everywhere, and convoluted things in some dark sides of the kernel.
>
> And it makes things rather slower for a lot of single threaded applications
> on modern systems. Yes, fget_light can be done much more cleanly, but
> please don't go around ripping out optimizations just because.

Sure. But I apparently was the only guy to react to the f_light horror story.

And it seems a solution was found, after some mail exchanges.

In French we have this expression : "Precher le faux pour savoir le vrai"

You could translate to "make false statements in order to discover the truth"
or "to tell a lie in order to get at the truth" or maybe "playing the devil's
advocate", but really the French one is better :)

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