Re: [PATCH v6 net-next 2/5] net: implement support for low latencysocket polling

[Eliezer Tamir]

On 29/05/2013 16:37, Eric Dumazet wrote:
> On Wed, 2013-05-29 at 09:39 +0300, Eliezer Tamir wrote:

> > +static inline unsigned long ll_end_time(void)
> > +{
> > +	return TSC_MHZ * ACCESS_ONCE(sysctl_net_ll_poll) + get_cycles();
> > +}
>
> This can overflow.
>
> Multiply is giving 32bits, as tsc_khz is an int, and sysctl_net_ll_poll
> is an int.
>
> unsigned long sysctl_net_ll_poll ?
OK

> Also, if we want this to work on i386, the correct type to use for
> ll_end_time(void) would be cycles_t

OK
I would be really surprised if someone uses this on an i386, but I guess 
you never know.

Thanks!
-Eliezer
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