sst-linux/crypto
Helge Deller df95378d40 crypto: xor - fix template benchmarking
[ Upstream commit ab9a244c396aae4aaa34b2399b82fc15ec2df8c1 ]

Commit c055e3eae0 ("crypto: xor - use ktime for template benchmarking")
switched from using jiffies to ktime-based performance benchmarking.

This works nicely on machines which have a fine-grained ktime()
clocksource as e.g. x86 machines with TSC.
But other machines, e.g. my 4-way HP PARISC server, don't have such
fine-grained clocksources, which is why it seems that 800 xor loops
take zero seconds, which then shows up in the logs as:

 xor: measuring software checksum speed
    8regs           : -1018167296 MB/sec
    8regs_prefetch  : -1018167296 MB/sec
    32regs          : -1018167296 MB/sec
    32regs_prefetch : -1018167296 MB/sec

Fix this with some small modifications to the existing code to improve
the algorithm to always produce correct results without introducing
major delays for architectures with a fine-grained ktime()
clocksource:
a) Delay start of the timing until ktime() just advanced. On machines
with a fast ktime() this should be just one additional ktime() call.
b) Count the number of loops. Run at minimum 800 loops and finish
earliest when the ktime() counter has progressed.

With that the throughput can now be calculated more accurately under all
conditions.

Fixes: c055e3eae0 ("crypto: xor - use ktime for template benchmarking")
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: John David Anglin <dave.anglin@bell.net>

v2:
- clean up coding style (noticed & suggested by Herbert Xu)
- rephrased & fixed typo in commit message

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:20:36 +02:00
..
asymmetric_keys
async_tx
842.c
acompress.c
adiantum.c
aead.c
aegis128-core.c
aegis128-neon-inner.c
aegis128-neon.c
aegis.h
aes_generic.c
aes_ti.c
af_alg.c
ahash.c
akcipher.c
algapi.c
algboss.c
algif_aead.c
algif_hash.c
algif_rng.c
algif_skcipher.c
ansi_cprng.c
anubis.c
api.c
arc4.c
aria_generic.c
authenc.c
authencesn.c
blake2b_generic.c
blowfish_common.c
blowfish_generic.c
camellia_generic.c
cast5_generic.c
cast6_generic.c
cast_common.c
cbc.c
ccm.c
cfb.c
chacha20poly1305.c
chacha_generic.c
cipher.c
cmac.c
compress.c
crc32_generic.c
crc32c_generic.c
crc64_rocksoft_generic.c
crct10dif_common.c
crct10dif_generic.c
cryptd.c
crypto_engine.c
crypto_null.c
crypto_user_base.c
crypto_user_stat.c
ctr.c
cts.c
curve25519-generic.c
deflate.c
des_generic.c
dh_helper.c
dh.c
drbg.c
ecb.c
ecc_curve_defs.h
ecc.c
ecdh_helper.c
ecdh.c
ecdsa.c
ecdsasignature.asn1
echainiv.c
ecrdsa_defs.h
ecrdsa_params.asn1
ecrdsa_pub_key.asn1
ecrdsa.c
essiv.c
fcrypt.c
fips.c
gcm.c
geniv.c
gf128mul.c
ghash-generic.c
hash_info.c
hctr2.c
hmac.c
internal.h
jitterentropy-kcapi.c
jitterentropy.c
jitterentropy.h
Kconfig
kdf_sp800108.c
keywrap.c
khazad.c
kpp.c
lrw.c
lz4.c
lz4hc.c
lzo-rle.c
lzo.c
Makefile
md4.c
md5.c
michael_mic.c
nhpoly1305.c
ofb.c
pcbc.c
pcrypt.c
poly1305_generic.c
polyval-generic.c
proc.c
ripemd.h
rmd160.c
rng.c
rsa_helper.c
rsa-pkcs1pad.c
rsa.c
rsaprivkey.asn1
rsapubkey.asn1
scatterwalk.c
scompress.c
seed.c
seqiv.c
serpent_generic.c
sha1_generic.c
sha3_generic.c
sha256_generic.c
sha512_generic.c
shash.c
simd.c
skcipher.c
sm2.c
sm2signature.asn1
sm3_generic.c
sm3.c
sm4_generic.c
sm4.c
streebog_generic.c
tcrypt.c
tcrypt.h
tea.c
testmgr.c
testmgr.h
twofish_common.c
twofish_generic.c
vmac.c
wp512.c
xcbc.c
xctr.c
xor.c crypto: xor - fix template benchmarking 2024-10-17 15:20:36 +02:00
xts.c
xxhash_generic.c
zstd.c