[OE-core] [PATCHv2] openssl: switch ARM builds from linux-elf-arm to linux-armv4 config

[Koen Kooi]

Op 16 okt. 2013, om 11:45 heeft Koen Kooi <koen at dominion.thruhere.net> het volgende geschreven:

> 
> Op 16 okt. 2013, om 11:20 heeft Phil Blundell <pb at pbcl.net> het volgende geschreven:
> 
>> On Wed, 2013-10-16 at 09:25 +0200, Koen Kooi wrote:
>>> From: Koen Kooi <koen.kooi at linaro.org>
>>> 
>>> This enables aes and sha1 assembly at buildtime. Openssl does a
>>> runtime check to see which portion gets enabled.
>> 
>> [...]
>> 
>>> Algo    blocksize       ops/s after
>>>               ops/s before    difference
>>> -------------------------------------------
>>> MD5	16	308,766	264,664	-14.28%
>>> 	64	277,090	263,340	-4.96%
>>> 	256	212,652	197,043	-7.34%
>>> 	1024	103,604	100,157	-3.33%
>>> 	8192	17,936	17,796	-0.78%
>> 
>> Do you know why it's causing MD5 to get slower?  I guess md5 with
>> blocksize=16 is not a very common case, but still.
> 
> I really don't know and it is the only algo that gets a lot slower. This patch is a preparation for (more) NEON optimizations which seem to fix the regression, see
> 
> 	https://docs.google.com/spreadsheet/ccc?key=0AhgZ33Tf6eBldHVONjRXRnItWld4eFlRWTJ3RzVIdGc&usp=sharing
> 
> and
> 
> 	http://dominion.thruhere.net/koen/angstrom/0002-openssl-1.0.1e-add-ARMv7-AES-optimizations.patch
> 
> I need to test that patch on A9 and A15 cores as well since it doesn't seem to do a lot on A8 cores :(

And on A9 cores linux-armv4 is 20% *faster* on MD5 with blocksize=16, see spreadsheet above. So it probably is a scheduling issue that favours A9 cores.

regards,

Koen.


> 
>> Also, it seems generally a bit unwholesome for openssl to be picking its
>> own CFLAGS at all.  Would it be better to just make it use the same
>> CFLAGS as everything else?
> 
> openssl.inc already pokes at CLAG(S):
> 
> CFLAG = "${@base_conditional('SITEINFO_ENDIANNESS', 'le', '-DL_ENDIAN', '-DB_ENDIAN', d)} \
>        -DTERMIO ${CFLAGS} -Wall -Wa,--noexecstack"
> 
> The complete command looks like this:
> 
> arm-angstrom-linux-gnueabi-gcc  -march=armv7-a -mthumb-interwork -mfloat-abi=hard -mfpu=neon -mtune=cortex-a8 --sysroot=/build/v2013.06/build/tmp-angstrom_v2013_06-eglibc/sysroots/beaglebone -I. -I.. -I../include  -fPIC -DOPENSSL_PIC -DOPENSSL_THREADS -D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -DL_ENDIAN  -DTERMIO  -O2 -pipe -g -feliminate-unused-debug-types -Wall -Wa,--noexecstack -DHAVE_CRYPTODEV -DUSE_CRYPTODEV_DIGESTS -DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_GF2m -DSHA1_ASM -DSHA256_ASM -DSHA512_ASM -DAES_ASM -DBSAES_ASM -DGHASH_ASM -c   -c -o armv4cpuid.o armv4cpuid.S
> 
> So the '$cflags       = -DTERMIO -O3 -Wall' in linux-armv4 gets overridden by OE, just like we want :)
> 
> regards,
> 
> Koen