Messages in this thread | | | Date | Sat, 15 Aug 2009 00:10:35 -0700 | From | Jeremy Fitzhardinge <> | Subject | Re: [PATCH] x86 : omit duplicate processing at pte_pgprot() |
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On 08/09/09 08:43, ohyama_sec@ariel-networks.com wrote: > I suggest following PATCH that omit duplicate processing of mask. > > pte_pgprot() macro [arch/x86/include/asm/pgtable.h] call pte_flags() [arch/x86/include/asm/pgtable_types.h] that return value is masked by PTE_FLAGS_MASK in pte_flags() function, and this macro also masks the returned value by PTE_FLAGS_MASK. >
It probably won't make any difference in practice, because gcc will do a common subexpression elimination for the "& PTE_FLAGS_MASK" between the inline function and its caller. But it does tidy things up a bit.
> I guess that we don't have to do the mask processing at pte_pgprot() macro because it has already been masked at pte_flags(). > So, how about the following PATCH ? > > <Hiroyasu OHYAMA> >
Please add a proper Signed-off-by: line.
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
J > diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h > index 3cc06e3..a0b454c 100644 > --- a/arch/x86/include/asm/pgtable.h > +++ b/arch/x86/include/asm/pgtable.h > @@ -265,7 +265,7 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) > return __pgprot(preservebits | addbits); > } > > -#define pte_pgprot(x) __pgprot(pte_flags(x) & PTE_FLAGS_MASK) > +#define pte_pgprot(x) __pgprot(pte_flags(x)) > > #define canon_pgprot(p) __pgprot(massage_pgprot(p)) > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > >
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