crypto: crypto4xx - increase context and scatter ring buffer elements
If crypto4xx is used in conjunction with dm-crypt, the available
ring buffer elements are not enough to handle the load properly.
On an aes-cbc-essiv:sha256 encrypted swap partition the read
performance is abyssal: (tested with hdparm -t)
/dev/mapper/swap_crypt:
Timing buffered disk reads: 14 MB in 3.68 seconds = 3.81 MB/sec
The patch increases both PPC4XX_NUM_SD and PPC4XX_NUM_PD to 256.
This improves the performance considerably:
/dev/mapper/swap_crypt:
Timing buffered disk reads: 104 MB in 3.03 seconds = 34.31 MB/sec
Furthermore, PPC4XX_LAST_SD, PPC4XX_LAST_GD and PPC4XX_LAST_PD
can be easily calculated from their respective PPC4XX_NUM_*
constant.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
1 file changed