Re: [PATCH v2 02/17] powerpc/cell: Move data segment faulting code out of cell platform

On Wed, 2014-10-01 at 16:47 +1000, Michael Ellerman wrote:

On Tue, 2014-30-09 at 10:34:51 UTC, Michael Neuling wrote:

quoted

From: Ian Munsie <redacted>
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__spu_trap_data_seg() currently contains code to determine the VSID and=

 ESID

quoted

required for a particular EA and mm struct.
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This code is generically useful for other co-processors.  This moves th=

e code

quoted

of the cell platform so it can be used by other powerpc code.  It also =

adds 1TB

quoted

segment handling which Cell didn't have.

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I'm not loving this.
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For starters the name "copro_data_segment()" doesn't contain any verbs, a=

nd it

doesn't tell me what it does.

Ok.

If we give it a name that says what it does, we get copro_get_ea_esid_and=

_vsid().

Or something equally ugly.

Ok

And then in patch 10 you move the bulk of the logic into calculate_vsid()=

.

That was intentional on my part.  I want this patch to be clear that
we're moving this code out of cell.  Then I wanted the optimisations to
be in a separate patch.  It does mean we touch the code twice in this
series, but I was hoping it would make it easier to review.  Alas. :-)

So instead can we:
 - add a small helper that does the esid calculation, eg. calculate_esid(=

) ?

 - factor out the vsid logic into a helper, calculate_vsid() ?
 - rework the spu code to use those, dropping __spu_trap_data_seg()
 - use the helpers in the cxl code

OK, I think I can do that.  I might change the name to something better
in this patch, but I'll leave these cleanups to the later patch 10.

Mikey