Re: [PATCH] [6/8] Account overlapped mappings in end_pfn_map

Andi Kleen
2008-02-11T14:24:22Z

On Monday 11 February 2008 15:16:31 Peter Zijlstra wrote:
>
> On Mon, 2008-02-11 at 14:27 +0100, Andi Kleen wrote:
>
> > Ok patch with hungarized variables appended.
>
> > -static void __meminit
> > +static unsigned long __meminit
> > phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end)
> > {
> > + unsigned long true_end;
> > pmd_t *pmd = pmd_offset(pud, 0);
> > spin_lock(&init_mm.page_table_lock);
> > - phys_pmd_init(pmd, address, end);
> > + true_end = phys_pmd_init(pmd, address, end);
> > spin_unlock(&init_mm.page_table_lock);
> > __flush_tlb_all();
> > + return true_end;
> > }
>
> Just for the record, Hungarian notation would have it like:
>
> ulTrueEnd

_pfn is variant of hungarian notation (just postfix instead of prefix);
that is why I referred to it.

Admittedly it was a little unfair pun with Ingo, but he really
asked for it in this case :-)

> http://en.wikipedia.org/wiki/Hungarian_notation
>
> And the kernel doesn't do that, to wit (from Documentation/CodingStyle):
>
> Linus Torvalds (against systems Hungarian): Encoding the type of a
> function into the name (so-called Hungarian notation) is brain damaged -
> the compiler knows the types anyway and can check those, and it only
> confuses the programmer.

xxx_pfn is exactly that.

BTW Coding style also recommends to use short variable names inside
functions. Ingo asked me actually to violate that:

"
LOCAL variable names should be short, and to the point. If you have
some random integer loop counter, it should probably be called "i".
Calling it "loop_counter" is non-productive, if there is no chance of it
being mis-understood. Similarly, "tmp" can be just about any type of
variable that is used to hold a temporary value.
"

I used r for result in this case which is 100% conform to coding style.

-Andi (trying to exit this thread)