Re: [PATCH] x86: fix apic.h unused but set warnings v2

From: Andi Kleen
Date: Mon Nov 08 2010 - 16:57:36 EST


Thomas Gleixner <tglx@xxxxxxxxxxxxx> writes:

> On Mon, 8 Nov 2010, Andi Kleen wrote:
>> static inline u32 native_apic_msr_read(u32 reg)
>> {
>> - u32 low, high;
>> + u32 low;
>>
>> if (reg == APIC_DFR)
>> return -1;
>>
>> - rdmsr(APIC_BASE_MSR + (reg >> 4), low, high);
>> - return low;
>> + rdmsrl(APIC_BASE_MSR + (reg >> 4), low);
>> + return (u32)low;
>
> What's the point of casting u32 to u32 ?

One of the earlier reviewers thought adding an explicit cast would make
the truncation in the code clearer. I didn't full agree either, but
still did the change.

-Andi
--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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