答复: 答复: [tip:x86/cpu] x86/cpu: Create Zhaoxin processors architecture support file

[Tony W Wang-oc]

On Tue, 25 Jun 2019, Thomas Gleixner wrote:
> Tony,
> 
> On Tue, 25 Jun 2019, Tony W Wang-oc wrote:
> > On Sun, Jun 23, 2019, Joe Perches wrote:
> > > > x86/cpu: Create Zhaoxin processors architecture support file
> > > >
> > > []
> > > > diff --git a/arch/x86/kernel/cpu/zhaoxin.c
> b/arch/x86/kernel/cpu/zhaoxin.c
> > > []
> > > > +static void init_zhaoxin_cap(struct cpuinfo_x86 *c)
> > > > +{
> > > > +	u32  lo, hi;
> > > > +
> > > > +	/* Test for Extended Feature Flags presence */
> > > > +	if (cpuid_eax(0xC0000000) >= 0xC0000001) {
> > > > +		u32 tmp = cpuid_edx(0xC0000001);
> > > > +
> > > > +		/* Enable ACE unit, if present and disabled */
> > > > +		if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
> > >
> > > trivia:
> > >
> > > Perhaps this is more intelligible for humans to read
> > > and it deduplicates the comment as:
> > >
> > > 		if ((tmp & ACE_PRESENT) && !(tmp & ACE_ENABLED))
> > >
> > > The compiler produces the same object code.
> > >
> >
> > Thanks for the trivia, I will change this in the next version patch set.
> 
> as you might have noticed from the tip bot commit notification mail, your
> patch set has been merged into the tip tree and is queued for the 5.3 merge
> window. So a new patch set is pointless. If at all then you can send a
> delta patch.
> 
> Though I have to say, that I prefer the existing check:
> 
> > > > +		if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
> 
> It's pretty clear, but that's really a matter of personal preference. So
> from my side there is nothing to do at all.

Got it, I will not change this code.

Thanks
TonyWWang-oc