powerpc: Streamline ret_from_except_lite for non-iSeries platforms

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There is a small passage of code in ret_from_except_lite which is
only required on iSeries.  For a multi-platform kernel on non-iSeries
machines this means we end up executing ~15 nops in ret_from_except_lite.

It would be nicer if non-iSeries could skip the code entirely, and on
iSeries we can jump out of line to execute the code.

I have no performance numbers to justify this, other than the assertion
that executing 15 nops takes longer than executing 0.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

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Michael Ellerman 2008-07-16 14:21:34 +10:00 • committed by Paul Mackerras

parent cd5aeb9f6c

commit 01f3880dd8

1 changed files with 29 additions and 24 deletions

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arch/powerpc/kernel/entry_64.S

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