Joe, Doug, Nicolas, The CONFIG patch change suggested by Joe and Doug makes sense to do. I'll do some additional testing to verify the performance on my systems. Jeff Lien -----Original Message----- From: Joe Perches [mailto:joe@xxxxxxxxxxx] Sent: Saturday, August 11, 2018 10:06 AM To: dgilbert@xxxxxxxxxxxx; Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> Cc: Jeffrey Lien <Jeff.Lien@xxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-crypto@xxxxxxxxxxxxxxx; linux-block@xxxxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx; herbert@xxxxxxxxxxxxxxxxxxx; tim.c.chen@xxxxxxxxxxxxxxx; martin.petersen@xxxxxxxxxx; David Darrington <david.darrington@xxxxxxx>; Jeff Furlong <jeff.furlong@xxxxxxx> Subject: Re: [PATCH] Performance Improvement in CRC16 Calculations. On Sat, 2018-08-11 at 02:04 -0700, Joe Perches wrote: > On Fri, 2018-08-10 at 22:39 -0400, Douglas Gilbert wrote: > > but below is a copy and paste of a table 27 from draft SBC-4 > > revision 15 in chapter 4.22.4.4 on page 87. > > The posted code returns the proper crc for each > CONFIG_CRYPTO_CRCT10DIF_TABLE_SIZE value from > 1 to 5 for these arrays. Jeff, could you please test the suggested patch with your comparison framework again with each CONFIG_CRYPTO_CRCT10DIF_TABLE_SIZE from 1 to 5? I get on a very limited test framework here: (runtime average of 10 runs) 1: 4.32 2: 1.86 3: 1.31 4: 1.05 5: 0.99