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Subject: Re: [PATCH v2 5/5] iommu/amd - Add a debugfs entry to specify a IOMMU
 device table entry
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
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From:   Gary R Hook <gary.hook@amd.com>
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Date:   Wed, 14 Mar 2018 10:24:45 -0500
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On 03/13/2018 03:56 PM, Andy Shevchenko wrote:
> On Tue, Mar 13, 2018 at 8:54 PM, Gary R Hook <gary.hook@amd.com> wrote:
>> On 03/13/2018 12:20 PM, Andy Shevchenko wrote:
> 
>>>> +       } else if (obuf[0] == '0' && obuf[1] == 'x') {
>>>> +               n = sscanf(obuf, "%x", &amd_iommu_devid);
>>>> +       } else {
>>>> +               n = sscanf(obuf, "%d", &amd_iommu_devid);
>>>> +       }
> 
>>> kstrtoint() ?
> 
>> I see various mechanisms for this sort of thing, and simply chose one.
>> Am happy to use whatever is preferred.
> 
> sscanf() has an enormous overhead for cases like this.
> 
> simple
> 
> ret = kstrtoint();
> if (ret)
>   ... do error handling ...
> 
> 

Gotcha. Fixed.

Thanks,
Gary