Re: [PATCH] crypto: serpent - add x86_64/avx assembler implementation

Quoting Johannes Goetzfried  
[off-list ref]:

Hello,

quoted

Should be serpent_sse2_glue.c?

Yeah, same error as in the other patch :-)

quoted

quoted

+}, {
+	.cra_name		= "ecb(serpent)",
+	.cra_driver_name	= "ecb-serpent-avx",
+	.cra_priority		= 400,

serpent_sse2_glue.c has priority 400 too, so you should increase
priority here to 500.

You are right. Actually it is useless to load both modules at the  
same time and
so this shouldn't be a problem. But better be safe. I'll resend this patch as
well.

Thing is that since both have MODULE_ALIAS(serpent), they both get  
loaded with 'modprobe serpent' etc.

quoted

Actually about duplicating glue code.. is it really needed? On
x86_64, both avx and sse2 versions process 8-blocks parallel and
therefore glue code could be easily shared (as is done in SHA1
SSSE3/AVX).

I thought about doing it the way as it is done in the SHA1-Module.  
But I don't
think that's a good idea, because then I had to compile both  
implementations in
the same module and decide at runtime which one to use depending on the
processor capabilities. This would result in an increasing object  
size and on a
specific processor only one implementation is used. I think it's better to
decide statically at compile-time which implementation to use.
I agree, the code duplication is ugly, and have a different approach. All the
glue code shared by both implementations can be moved to a  
serpent_common_glue.c
file and only the module init stuff needs to be seperate. This should reduce
the code size and keeps the possibility of compiling only one  
implementation. I
will send a second patch which should do the job.

Looks better.

Maybe later when I have time, I'll check if all glue code for 16-byte  
block-ciphers found in arch/x86/crypto could be merged in to single  
helper module.

-Jussi