Am 2016-04-11 08:16, schrieb Rolf Eike Beer:
Am Samstag, 9. April 2016, 08:26:14 schrieb Helge Deller:
This patch simplifies the code for get_user() and put_user() a lot.
Instead of accessing kernel memory (%sr0) and userspace memory (%sr3)
hard-coded in the assembler instruction, we now preload %sr2 with
either
%sr0 (for accessing KERNEL_DS) or with sr3 (to access USER_DS) and
use %sr2 in the load directly.
The generated code avoids a branch and speeds up execution by
generating
less assembler instructions.
I have put this on my C3600 (Linux 4.5.0, 32 bit kernel) and I see no
negative
effects.
It's not 4.5.0, it's 4.4.6.
Eike
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