Re: [PATCH v2 03/13] sh: remove unaligned access for sh4a

John Paul Adrian Glaubitz
2021-05-14T10:34:50Z

Hi Arnd!

On 5/14/21 12:00 PM, Arnd Bergmann wrote:
> Unlike every other architecture, sh4a uses an inline asm implementation
> for get_unaligned(). I have shown that this produces better object
> code than the asm-generic version. However, there are very few users of
> arch/sh/ overall, and most of those seem to use sh4 rather than sh4a CPU
> cores, so it seems not worth keeping the complexity in the architecture
> independent code.

My Renesas SH4-Boards actually run an sh4a-Kernel, not an sh4-Kernel:

root@tirpitz:~> uname -a
Linux tirpitz 5.11.0-rc4-00012-g10c03c5bf422 #161 PREEMPT Mon Jan 18 21:10:17 CET 2021 sh4a GNU/Linux
root@tirpitz:~>

So, if this change reduces performance on sh4a, I would rather not merge it.

Adrian

--
.''`. John Paul Adrian Glaubitz
: :' : Debian Developer - glaubitz@debian.org
`. `' Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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