4.4-stable review patch. If anyone has any objections, please let me know.
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From: Christian Lamparter chunkeey@gmail.com
[ Upstream commit 778f81d6cdb7d25360f082ac0384d5103f04eca5 ]
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 Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/crypto/amcc/crypto4xx_core.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
--- a/drivers/crypto/amcc/crypto4xx_core.h +++ b/drivers/crypto/amcc/crypto4xx_core.h @@ -32,12 +32,12 @@ #define PPC405EX_CE_RESET 0x00000008
#define CRYPTO4XX_CRYPTO_PRIORITY 300 -#define PPC4XX_LAST_PD 63 -#define PPC4XX_NUM_PD 64 -#define PPC4XX_LAST_GD 1023 +#define PPC4XX_NUM_PD 256 +#define PPC4XX_LAST_PD (PPC4XX_NUM_PD - 1) #define PPC4XX_NUM_GD 1024 -#define PPC4XX_LAST_SD 63 -#define PPC4XX_NUM_SD 64 +#define PPC4XX_LAST_GD (PPC4XX_NUM_GD - 1) +#define PPC4XX_NUM_SD 256 +#define PPC4XX_LAST_SD (PPC4XX_NUM_SD - 1) #define PPC4XX_SD_BUFFER_SIZE 2048
#define PD_ENTRY_INUSE 1